Rapid Micro Biosystems (RPID) 10-Q 15 Nov 21 2021 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2021	Nov. 01, 2021
Document Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Sep. 30, 2021
Entity File Number	001-40592
Entity Registrant Name	Rapid Micro Biosystems, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-8121647
Entity Address State Or Province	MA
Entity Address, Address Line One	1001 Pawtucket Boulevard West
Entity Address, Address Line Two	Suite 280
Entity Address, City or Town	Lowell
Entity Address, Postal Zip Code	01854
City Area Code	978
Local Phone Number	349-3200
Title of 12(b) Security	Class A common stock, $0.01 par value per share
Trading Symbol	RPID
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	true
Entity Ex Transition Period	false
Entity Shell Company	false
Entity Central Index Key	0001380106
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false
Common Class A
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		34,449,144
Common Class B
Document Information [Line Items]
Entity Common Stock, Shares Outstanding		6,903,379

Condensed consolidated balance

Condensed consolidated balance sheets - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 219,588,000	$ 30,079,000
Short-term investments	0	14,998,000
Accounts receivable	5,006,000	4,988,000
Inventory	14,167,000	8,965,000
Prepaid expenses and other current assets	5,400,000	3,120,000
Total current assets	244,161,000	62,150,000
Property and equipment, net	8,633,000	7,052,000
Other long-term assets	1,348,000	695,000
Restricted cash	284,000	100,000
Total assets	254,426,000	69,997,000
Current liabilities:
Accounts payable	2,251,000	4,468,000
Accrued expenses and other current liabilities	11,566,000	6,654,000
Deferred revenue	3,903,000	4,423,000
Total current liabilities	17,720,000	15,545,000
Preferred stock warrant liability		4,117,000
Notes payable, net of unamortized discount		24,810,000
Deferred rent, long term	728,000	705,000
Other long-term liabilities	1,233,000
Total liabilities	19,681,000	45,177,000
Commitments and contingencies (Note 16)
Redeemable convertible preferred stock (Series A1, B1, C1, C2, D1, and D2), $0.01 par value; zero shares and 161,455,689 shares authorized at September 30, 2021 and December 31, 2020, respectively; zero shares and 133,021,640 shares issued and outstanding at September 30, 2021 and December 31, 2020, respectively.		151,826,000
Stockholders' equity (deficit):
Preferred stock, $0.01 par value: 10,000,000 shares and zero shares authorized at September 30, 2021 and December 31, 2020, respectively; zero shares issued and outstanding at September 30, 2021 and December 31, 2020
Additional paid-in capital	534,839,000	114,575,000
Accumulated deficit	(300,507,000)	(241,588,000)
Accumulated other comprehensive income		1,000
Total stockholders' equity (deficit)	234,745,000	(127,006,000)
Total liabilities, redeemable convertible preferred stock and stockholders' equity (deficit)	254,426,000	69,997,000
Common Class A
Stockholders' equity (deficit):
Common stock	344,000	$ 6,000
Common Class B
Stockholders' equity (deficit):
Common stock	$ 69,000

Condensed consolidated balanc_2

Condensed consolidated balance sheets (Parentheticals) - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Redeemable convertible preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Redeemable convertible preferred stock, authorized (in shares)	0	161,455,689
Redeemable convertible preferred stock, issued (in shares)	0	133,021,640
Redeemable convertible preferred stock, outstanding (in shares)	0	133,021,640
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, authorized (in shares)	10,000,000	0
Preferred stock, issued (in shares)	0	0
Common Class A
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	210,000,000	35,000,000
Common stock, issued (in shares)	34,449,154	612,850
Common stock, outstanding (in shares)	34,449,154	612,850
Common Class B
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, authorized (in shares)	10,000,000	0
Common stock, issued (in shares)	6,903,379	0
Common stock, outstanding (in shares)	6,903,379	0

Condensed consolidated statemen

Condensed consolidated statements of operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue:
Total revenue	$ 6,899	$ 5,247	$ 18,024	$ 10,839
Costs and operating expenses:
Research and development	2,441	2,224	6,926	4,906
Sales and marketing	3,063	1,447	8,460	4,149
General and administrative	5,308	2,541	12,135	6,855
Total costs and operating expenses	19,022	12,824	50,700	31,664
Loss from operations	(12,123)	(7,577)	(32,676)	(20,825)
Other income (expense):
Interest expense	(775)	(886)	(2,631)	(2,463)
Change in fair value of preferred stock warrant liability	(8,160)		(19,643)	549
Loss on extinguishment of debt	(3,100)		(3,100)	(2,910)
Other income (expense)	(809)	18	(812)	24
Total other income (expense), net	(12,844)	(868)	(26,186)	(4,800)
Loss before income taxes	(24,967)	(8,445)	(58,862)	(25,625)
Income tax expense	20	20	57	114
Net loss	(24,987)	(8,465)	(58,919)	(25,739)
Accretion of redeemable convertible preferred stock to redemption value	210	(832)	(1,761)	(2,882)
Cumulative redeemable convertible preferred stock dividends	(451)	(1,412)	(2,747)	(2,987)
Net loss attributable to common stockholders - basic	(25,228)	(10,709)	(63,427)	(31,608)
Net loss attributable to common stockholders - diluted	$ (25,228)	$ (10,709)	$ (63,427)	$ (31,608)
Net loss per share attributable to common stockholders - basic	$ (0.71)	$ (30.08)	$ (5.14)	$ (89.20)
Net loss per share attributable to common stockholders - diluted	$ (0.71)	$ (30.08)	$ (5.14)	$ (89.20)
Weighted average common shares outstanding - basic	35,316,099	356,074	12,344,619	354,341
Weighted average common shares outstanding - diluted	35,316,099	356,074	12,344,619	354,341
Product revenue
Revenue:
Total revenue	$ 4,824	$ 4,069	$ 12,630	$ 6,921
Costs and operating expenses:
Cost of product revenue	6,298	5,441	17,900	11,544
Service revenue
Revenue:
Total revenue	1,479	895	4,152	2,060
Costs and operating expenses:
Cost of product revenue	1,516	772	3,997	2,478
Non-commercial revenue
Revenue:
Total revenue	596	283	1,242	1,858
Costs and operating expenses:
Cost of product revenue	$ 396	$ 399	$ 1,282	$ 1,732

Condensed consolidated statem_2

Condensed consolidated statements of comprehensive loss - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Consolidated statements of comprehensive loss
Net loss	$ (24,987,000)	$ (8,465,000)	$ (58,919,000)	$ (25,739,000)
Other comprehensive income:
Unrealized loss on short-term investments, net of tax			(1,000)	0
Comprehensive loss	$ (24,987,000)	$ (8,465,000)	$ (58,920,000)	$ (25,739,000)

Condensed consolidated statem_3

Condensed consolidated statements of redeemable convertible preferred stock and stockholders' deficit - USD ($) $ in Thousands	Common StockCommon Class A	Common StockCommon Class B	Additional paid-in capitalCommon Class A	Additional paid-in capital	Accumulated deficit	Accumulated Other Comprehensive Income (Loss)	Series C1 Redeemable Convertible Preferred Stock	Series C2 Redeemable Convertible Preferred Stock	Series D1 Redeemable Convertible Preferred Stock	Series D2 Redeemable Convertible Preferred Stock	Common Class A	Total
Balance at Dec. 31, 2019												$ 81,850
Balance (shares) at Dec. 31, 2019												78,757,540
Increase (Decrease) in Temporary Equity [Roll Forward]
Accretion of redeemable convertible preferred stock to redemption value												$ 818
Cumulative redeemable convertible preferred stock dividends												788
Balance at Mar. 31, 2020												$ 83,456
Balance (shares) at Mar. 31, 2020												78,757,540
Balance at Dec. 31, 2019	$ 4			$ 121,931	$ (204,510)							$ (82,575)
Balance (shares) at Dec. 31, 2019	353,465
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accretion of redeemable convertible preferred stock to redemption value				(818)								(818)
Cumulative redeemable convertible preferred stock dividends				(788)								(788)
Stock based compensation expense				120								120
Net loss					(8,007)							(8,007)
Balance at Mar. 31, 2020	$ 4			120,445	(212,517)							(92,068)
Balance (shares) at Mar. 31, 2020	353,465
Balance at Dec. 31, 2019												$ 81,850
Balance (shares) at Dec. 31, 2019												78,757,540
Increase (Decrease) in Temporary Equity [Roll Forward]
Conversion of bridge notes to redeemable convertible preferred stock												$ 9,523
Balance at Sep. 30, 2020												$ 149,552
Balance (shares) at Sep. 30, 2020												133,021,640
Balance at Dec. 31, 2019	$ 4			121,931	(204,510)							$ (82,575)
Balance (shares) at Dec. 31, 2019	353,465
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss												(25,739)
Balance at Sep. 30, 2020	$ 4			116,428	(230,249)							(113,817)
Balance (shares) at Sep. 30, 2020	358,465
Balance at Mar. 31, 2020												$ 83,456
Balance (shares) at Mar. 31, 2020												78,757,540
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of redeemable convertible preferred stock, net of issuance costs							$ 26,891	$ 23,044
Issuance of redeemable convertible preferred stock, net of issuance costs (in shares)							23,611,208	20,301,829
Conversion of bridge notes to redeemable convertible preferred stock							$ 11,898
Conversion of bridge notes to redeemable convertible preferred stock (In shares)							10,351,063
Accretion of redeemable convertible preferred stock to redemption value												$ 1,232
Cumulative redeemable convertible preferred stock dividends												787
Balance at Jun. 30, 2020												$ 147,308
Balance (shares) at Jun. 30, 2020												133,021,640
Balance at Mar. 31, 2020	$ 4			120,445	(212,517)							$ (92,068)
Balance (shares) at Mar. 31, 2020	353,465
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accretion of redeemable convertible preferred stock to redemption value				(1,232)								(1,232)
Cumulative redeemable convertible preferred stock dividends				(787)								(787)
Stock based compensation expense				126								126
Net loss					(9,267)							(9,267)
Balance at Jun. 30, 2020	$ 4			118,552	(221,784)							(103,228)
Balance (shares) at Jun. 30, 2020	353,465
Increase (Decrease) in Temporary Equity [Roll Forward]
Accretion of redeemable convertible preferred stock to redemption value												832
Cumulative redeemable convertible preferred stock dividends												1,412
Balance at Sep. 30, 2020												$ 149,552
Balance (shares) at Sep. 30, 2020												133,021,640
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options				5								$ 5
Issuance of common stock upon exercise of stock options (In shares)	5,000
Accretion of redeemable convertible preferred stock to redemption value				(832)								(832)
Cumulative redeemable convertible preferred stock dividends				(1,412)								(1,412)
Stock based compensation expense				115								115
Net loss					(8,465)							(8,465)
Balance at Sep. 30, 2020	$ 4			116,428	(230,249)							(113,817)
Balance (shares) at Sep. 30, 2020	358,465
Balance at Dec. 31, 2020							$ 40,632	$ 24,141				$ 151,826
Balance (shares) at Dec. 31, 2020							33,962,271	20,301,829				133,021,640
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of redeemable convertible preferred stock, net of issuance costs									$ 78,338	$ 1,470
Issuance of redeemable convertible preferred stock, net of issuance costs (in shares)									22,086,725	413,268
Accretion of redeemable convertible preferred stock to redemption value												$ 787
Cumulative redeemable convertible preferred stock dividends												1,411
Balance at Mar. 31, 2021												$ 233,832
Balance (shares) at Mar. 31, 2021												155,521,633
Balance at Dec. 31, 2020	$ 6			114,575	(241,588)	$ 1						$ (127,006)
Balance (shares) at Dec. 31, 2020	612,850
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options	$ 1			66								67
Issuance of common stock upon exercise of stock options (In shares)	67,418
Accretion of redeemable convertible preferred stock to redemption value				(787)								(787)
Cumulative redeemable convertible preferred stock dividends				(1,411)								(1,411)
Issuance of restricted common stock awards	$ 2			(2)
Issuance of restricted common stock awards (in shares)	248,903
Stock based compensation expense				191								191
Net loss					(22,101)							(22,101)
Balance at Mar. 31, 2021	$ 9			112,632	(263,689)	1						(151,047)
Balance (shares) at Mar. 31, 2021	929,171
Balance at Dec. 31, 2020							$ 40,632	$ 24,141				$ 151,826
Balance (shares) at Dec. 31, 2020							33,962,271	20,301,829				133,021,640
Balance (shares) at Sep. 30, 2021												0
Balance at Dec. 31, 2020	$ 6			114,575	(241,588)	1						$ (127,006)
Balance (shares) at Dec. 31, 2020	612,850
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options (In shares)												111,149
Net loss												$ (58,919)
Balance at Sep. 30, 2021	$ 344	$ 69		534,839	(300,507)							234,745
Balance (shares) at Sep. 30, 2021	34,449,154	6,903,379
Balance at Mar. 31, 2021												$ 233,832
Balance (shares) at Mar. 31, 2021												155,521,633
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance costs									$ (64)	$ (1)
Accretion of redeemable convertible preferred stock to redemption value												$ 1,184
Cumulative redeemable convertible preferred stock dividends												885
Balance at Jun. 30, 2021												235,836
Balance at Mar. 31, 2021	$ 9			112,632	(263,689)	1						(151,047)
Balance (shares) at Mar. 31, 2021	929,171
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options	$ 1			31								32
Issuance of common stock upon exercise of stock options (In shares)	37,146
Accretion of redeemable convertible preferred stock to redemption value				(1,184)								(1,184)
Cumulative redeemable convertible preferred stock dividends				(885)								(885)
Stock based compensation expense				390								390
Net loss					(11,831)							(11,831)
Other comprehensive income						$ (1)						(1)
Balance at Jun. 30, 2021	$ 10			110,984	(275,520)							$ (164,526)
Balance (shares) at Jun. 30, 2021	966,317											155,521,633
Increase (Decrease) in Temporary Equity [Roll Forward]
Accretion of redeemable convertible preferred stock to redemption value												$ (210)
Conversion of preferred stock to common stock												(236,077)
Accretion of redeemable convertible preferred stock to redemption value				210								210
Cumulative redeemable convertible preferred stock dividends												$ 451
Balance (shares) at Sep. 30, 2021												0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Issuance of common stock upon exercise of stock options				15								$ 15
Issuance of common stock upon exercise of stock options (In shares)	6,595
Cumulative redeemable convertible preferred stock dividends				(451)								(451)
Conversion of preferred stock to common stock	$ 242	$ 69	$ 23,760	235,766							$ 23,760	236,077
Conversion of preferred stock to common stock (in shares)	24,200,920	6,903,379
Issuance of class A common stock in initial public offering, net of issuance costs of $16,087	$ 90			163,955								164,045
Issuance of class A common stock in initial public offering, net of issuance costs of $16,087 (in shares)	9,006,604
RSA liability accretion				5								5
Issuance of common stock upon exercise of common stock warrants	$ 2			11								13
Issuance of common stock upon exercise of common stock warrants (in shares)	268,718
Stock based compensation expense				584								584
Net loss					(24,987)							(24,987)
Balance at Sep. 30, 2021	$ 344	$ 69		$ 534,839	$ (300,507)							$ 234,745
Balance (shares) at Sep. 30, 2021	34,449,154	6,903,379
Increase (Decrease) in Temporary Equity [Roll Forward]
Conversion of preferred stock to common stock (in shares)												(155,521,633)

Condensed consolidated statem_4

Condensed consolidated statements of redeemable convertible preferred stock and stockholders' deficit (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Sep. 30, 2021	Mar. 31, 2021	Jun. 30, 2020
Series C1 Redeemable Convertible Preferred Stock
Issuance costs			$ 261
Series C2 Redeemable Convertible Preferred Stock
Issuance costs			$ 303
Series D1 Redeemable Convertible Preferred Stock
Issuance costs		$ 2,627
Series D2 Redeemable Convertible Preferred Stock
Issuance costs		$ 18
Common Class A
Issuance costs	$ 16,087

Condensed consolidated statem_5

Condensed consolidated statements of cash flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Cash flows from operating activities:
Net loss	$ (58,919)	$ (25,739)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization expense	1,079	1,190
Stock-based compensation expense	1,165	361
Change in fair value of preferred stock warrant liability	19,643	(549)
Provision recorded for inventory	44
Noncash interest expense	390	1,378
Gain on disposal of property and equipment	(18)
Accretion on investments	(4)	(11)
Loss on extinguishment of debt	3,100	2,910
Changes in operating assets and liabilities
Accounts receivable	(18)	(2,036)
Inventory	(5,247)	(2,531)
Prepaid expenses and other current assets	(2,552)	(579)
Other long-term assets	(653)	(591)
Accounts payable	(2,216)	(1,613)
Accrued expenses and other current liabilities	2,646	618
Deferred revenue	(520)	1,295
Deferred rent, long term	22	72
Other long-term liabilities	(19)
Net cash used in operating activities	(42,077)	(25,825)
Cash flows from investing activities:
Purchases of property and equipment	(1,251)	(566)
Proceeds from sale of property and equipment	20
Purchases of investments		(24,980)
Maturity of investments	15,000
Net cash provided by (used in) investing activities	13,769	(25,546)
Cash flows from financing activities:
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs	79,743	49,935
Proceeds from issuance of common stock upon option exercise	294	5
Proceeds from issuance of restricted stock award	523
Proceeds from initial public offering of Class A common stock, net of issuance costs	165,453
Proceeds from exercise of common stock warrants	13
Proceeds from issuance of convertible notes, net of issuance costs		9,500
Proceeds from issuance of notes payable, net of issuance costs		25,000
Payments of debt issuance costs		(857)
Repayment of term loans	(26,159)	(18,000)
Payment of debt extinguishment fees	(1,866)	(1,398)
Net cash provided by financing activities	218,001	64,185
Net increase in cash, cash equivalents and restricted cash	189,693	12,814
Cash, cash equivalents and restricted cash at beginning of period	30,179	12,611
Cash, cash equivalents and restricted cash at end of period	219,872	25,425
Supplemental disclosure of cash flow information
Cash paid for interest	1,891	979
Supplemental disclosure of non-cash investing activities
Establishment of property and equipment retirement cost asset	188
Purchases of property and equipment in accounts payable	857	14
Supplemental disclosure of non-cash financing activities
Conversion of convertible notes to Series C1 preferred stock		9,523
Issuance of preferred stock warrants in connection with redeemable convertible preferred stock		652
Initial fair value of derivative liability		2,375
Assets acquired under capital lease	372
Offering costs included in accounts payable and accrued expenses	1,408
Conversion of preferred stock to common stock	235,766
Conversion of preferred stock warrants to common stock warrants	23,760
Accretion of redeemable convertible preferred stock to redemption value	1,761	2,882
Cumulative redeemable convertible preferred stock dividends	$ 2,747	$ 2,987

Nature of the business and basi

Nature of the business and basis of presentation	9 Months Ended
	Sep. 30, 2021
Nature of the business and basis of presentation
Nature of the business and basis of presentation	1. Nature of the business and basis of presentation Rapid Micro Biosystems, Inc. (the “Company”) was incorporated under the laws of the State of Delaware on December 29, 2006. The Company develops, manufactures, markets and sells Growth Direct systems (“Systems”) proprietary consumables, laboratory information management system (“LIMS”) connection software, and services to address rapid microbial analysis used for quality control in the manufacture of pharmaceuticals, medical devices and personal care products. The Company’s technology uses a highly sensitive camera and the natural auto fluorescence of living cells to identify and quantify microbial growth faster and more accurately than the traditional method, which relies on the human eye. The Company currently sells to customers in North America, Europe and Asia. The Company is headquartered in Lowell, Massachusetts. The Company is subject to risks and uncertainties common to companies in the pharmaceutical and biotech quality control laboratory testing and instrumentation industry including, but not limited to, the successful development, commercialization, marketing and sale of products, fluctuations in operating results and financial risks, protection of proprietary knowledge and patent risks, dependence on key personnel, competition, technological and medical risks, customer demand, compliance with governmental regulations and management of growth. Potential risks and uncertainties also include, without limitation, uncertainties regarding the duration and magnitude of the impact of the ongoing COVID-19 pandemic on the Company’s business and the economy in general. Products currently under development will require additional research and development efforts prior to commercialization and will require additional capital and adequate personnel and infrastructure. The Company’s research and development may not be successfully completed, adequate protection for the Company’s technology may not be obtained, the Company may not obtain necessary government regulatory approval, and approved products may not prove commercially viable. The Company operates in an environment of rapid change in technology and competition. In March 2020, the World Health Organization declared the global novel coronavirus disease 2019 (“COVID-19”) outbreak a pandemic. The impact of this pandemic has been and may continue to be extensive in many aspects of society, which has resulted in and may continue to result in significant disruptions to the global economy, as well as businesses and capital markets around the world. The Company cannot at this time predict the ultimate extent, duration, or full impact that the COVID-19 pandemic will have on its future financial condition and operations. The impact of the ongoing COVID-19 pandemic on the Company’s financial performance will depend on future developments, including the duration and spread of the pandemic and related governmental advisories and restrictions. These developments and the impact of COVID-19, and its variants, on the financial markets and the overall economy are highly uncertain and cannot be predicted. If the financial markets and/or the overall economy are impacted for an extended period, the Company’s results may be materially adversely affected. Future impacts to the Company’s business as a result of COVID-19, and its variants, could include disruptions to the Company’s manufacturing operations and supply chain caused by facility closures, reductions in operating hours, staggered shifts and other social distancing efforts; labor shortages; decreased productivity and unavailability of materials or components; limitations on its employees’ and customers’ ability to travel, and delays in shipments to and from affected countries and within the United States. While the Company maintains an inventory of finished products and raw materials used in its products, a prolonged pandemic could lead to shortages in the raw materials necessary to manufacture its products. Basis of presentation These condensed consolidated financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) and include the accounts of the Company and its wholly owned subsidiaries in Germany and Switzerland. All intercompany accounts and transactions have been eliminated in consolidation. Certain information and note disclosures normally included in the consolidated financial statements prepared in accordance with GAAP have been condensed or omitted. Therefore, these condensed consolidated financial statements should be read in conjunction with the consolidated financial statements and notes included in the Company’s audited consolidated financial statements for the year ended December 31, 2020, included in the Company’s prospectus, dated July 14, 2021, filed with the Securities and Exchange Commission (“SEC”) in accordance with Rule 424(b) of the Securities Act on July 16, 2021 (the “Prospectus”). Any reference in these notes to applicable guidance is meant to refer to the authoritative GAAP as found in the Accounting Standards Codification (“ASC”) and Accounting Standards Update (“ASU”) of the Financial Accounting Standards Board (“FASB”). The unaudited interim condensed consolidated financial statements have been prepared on the same basis as the audited annual consolidated financial statements and, in the opinion of management, reflect all adjustments, which include only normal recurring adjustments, necessary for the fair statement of the Company’s financial position as of September 30, 2021 and the results of its operations for the three and nine months ended September 30, 2021 and 2020, and its cash flows for the nine months ended September 30, 2021 and 2020. The financial data and other information disclosed in these notes related to the three and nine months ended September 30, 2021 and 2020 are also unaudited. The results for the three and nine months ended September 30, 2021 are not necessarily indicative of results to be expected for the year ending December 31, 2021, any other interim periods, or any future year or period. Reverse split On July 9, 2021, the Company effected a one Initial public offering On July 19, 2021, the Company closed an initial public offering (“IPO”) of its Class A common stock, which resulted in the sale of 7,920,000 shares of its Class A common stock at a public offering price of $20.00 per share, before underwriting discounts. The offering resulted in gross proceeds of $158.4 million and net proceeds to the Company of approximately $143.8 million from the initial public offering after deducting underwriting discounts, commissions and estimated offering expenses payable by the Company. On August 4, 2021, the underwriters exercised their overallotment option in part and purchased 1,086,604 shares of Class A common stock at the initial public offering price of $20.00 per share less underwriting discounts and commissions. The overallotment option exercise resulted in net proceeds of approximately $20.2 million. Going concern The Company has evaluated whether there are certain conditions and events, considered in the aggregate, that raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the condensed consolidated financial statements are issued. Through September 30, 2021, the Company has funded its operations primarily with proceeds from product, service and non-commercial revenue, proceeds from sales of its redeemable convertible preferred stock, including borrowings under convertible debt arrangements that subsequently converted into redeemable convertible preferred stock, and from the issuance of term loans, and proceeds from the IPO. The Company has incurred recurring losses since its inception, including net losses of $25.0 million and $8.5 million for the three months ended September 30, 2021 and 2020, respectively, and net losses of $58.9 million and $25.7 million for the nine months ended September 30, 2021 and 2020, respectively. As of September 30, 2021, the Company had an accumulated deficit of $300.5 million. The Company expects to continue to generate significant operating losses for the foreseeable future. As of November 15, 2021, the date these interim condensed consolidated financial statements were issued, the Company expects that its existing cash and cash equivalents will be sufficient to fund its operating expenses and capital expenditure requirements for at least twelve months following the date these condensed consolidated financial statements were issued. The consolidated financial statements have been prepared on a basis that assumes the Company will continue as a going concern and which contemplates the realization of assets and satisfaction of liabilities and commitments in the ordinary course of business.

Summary of significant accounti

Summary of significant accounting policies	9 Months Ended
	Sep. 30, 2021
Summary of significant accounting policies
Summary of significant accounting policies	2. Use of estimates The preparation of the Company’s condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, calculating the standalone selling price for revenue recognition, the valuation of inventory, the valuation of common stock and stock-based awards, and the valuation of the preferred stock warrant liability. The Company bases its estimates on historical experience, known trends and other market-specific and relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates when there are changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates. Due to the COVID-19 pandemic, there has been uncertainty and disruption in the global economy and financial markets. The Company is not aware of any specific event or circumstance that would require an update to its estimates or judgments or a revision of the carrying value of its assets or liabilities. These estimates may change as new events occur and additional information is obtained. Other than policies noted below, there have been no significant changes to the significant accounting policies disclosed in Note 2 of the audited consolidated financial statements as of December 31, 2020 and 2019 and for the years ended December 31, 2020 and 2019, included in the Prospectus. Risk of concentrations of credit, significant customers and significant suppliers Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents, short-term investments and accounts receivable. Periodically, the Company maintains deposits in accredited financial institutions in excess of federally insured limits. The Company maintains its cash and cash equivalents with financial institutions that management believes to be of high credit quality. The Company has not experienced any losses on such accounts and does not believe it is exposed to any unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company has not experienced any other-than-temporary losses with respect to its cash equivalents and investments and does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. Significant customers are those which represent more than 10% of the Company’s total revenue or accounts receivable balance at each respective balance sheet date. The following table presents customers that represent 10% or more of the Company’s total revenue: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, ​ Nine Months Ended September 30, ​ 2021 2020 2021 2020 Customer A 32.1 % 40.8 % 16.4 % 21.2 % Customer B * ​ * ​ * ​ 17.1 % Customer C * ​ * ​ * ​ 10.1 % Customer D ​ 11.4 % * ​ ​ * ​ * ​ Customer E ​ * ​ 18.8 % ​ * ​ * ​ ​ 43.5 % 59.6 % 16.4 % 48.4 % * – less than 10% The following table presents customers that represent 10% or more of the Company’s accounts receivable: ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, 2020 ​ 2021 2020 Customer A ​ 21.7 % 41.9 % Customer D ​ 20.2 % * ​ Customer E 11.1 % * ​ Customer F * ​ 10.1 % Customer G * ​ 13.4 % Customer H * ​ 18.7 % ​ 53.0 % 84.1 % * – less than 10% Deferred offering costs The Company capitalizes certain legal, accounting and other third-party fees that are directly associated with in-process equity financings as deferred offering costs until such financings are consummated. After consummation of an equity financing, these costs are recorded in stockholders’ equity (deficit) as a reduction of additional paid-in capital generated as a result of the offering or as a reduction to the carrying value of redeemable convertible preferred stock. If the in-process equity financing is abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the condensed consolidated statements of operations. As of September 30, 2021 and December 31, 2020, the Company had zero and $0.1 million, respectively, in deferred offering costs in the condensed consolidated balance sheets. Debt issuance costs The Company capitalizes certain legal and other third-party fees that are directly associated with the issuance of debt as debt issuance costs. Debt issuance costs are recorded as a direct reduction of the carrying amount of the associated debt on the condensed consolidated balance sheets and amortized as interest expense on the condensed consolidated statements of operations using the effective interest method, which approximates the straight-line method. As of September 30, 2021 and December 31, 2020, debt issuance costs totaled zero and $1.3 million, respectively. During the three months ended September 30, 2021 and 2020, the Company recorded $0.1 million in the respective periods, and during the nine months ended September 30, 2021 and 2020, the Company recorded $0.4 million and $0.7 million, respectively, of interest expense related to amortization of debt issuance costs in the condensed consolidated statement of operations. Cash equivalents The Company considers all highly liquid investments with an original maturity of 90 days or less at the time of purchase to be cash equivalents. Cash equivalents that are readily convertible to cash are stated at cost, which approximates fair value. At September 30, 2021 and December 31, 2020, the Company held cash of $0.4 million and $0.1 million, respectively, in banks located outside of the United States. Restricted cash As of September 30, 2021 and December 31, 2020, the Company was required to maintain guaranteed investment certificates of $0.3 million and $0.1 million, respectively, with maturities of three months to one year that are subject to an insignificant risk of changes in value. The guaranteed investment certificates are held for the benefit of the landlord in connection with an operating lease which has a remaining term of greater than one year and are classified as restricted cash (non-current) on the Company’s consolidated balance sheets. Software Development Costs The Company accounts for software development costs for internal-use software under the provisions of ASC 350-40, “Internal-Use Software Fair value measurements Certain assets and liabilities of the Company are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: ● Level 1—Quoted prices in active markets for identical assets or liabilities. ● Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. ● Level 3—Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. The Company’s cash equivalents, short-term investments and its redeemable convertible preferred stock warrant liability are carried at fair value, determined according to the fair value hierarchy described above (see Note 3). The carrying values of the Company’s accounts receivable, prepaid expenses and other current assets, accounts payable and accrued expenses and other current liabilities approximate their fair values due to the short-term nature of these assets and liabilities. The carrying value of the Company’s long-term debt approximates its fair value (a level 2 measurement) at each balance sheet date due to its variable interest rate, which approximates a market interest rate. Product warranties The Company offers a one-year limited assurance warranty on System sales, which is included in the selling price. The warranty accrual is included in accrued expenses and other current liabilities in the condensed consolidated balance sheets. The following table presents a summary of changes in the amount reserved for warranty cost (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Balance, beginning of the period ​ $ 612 ​ $ 757 ​ $ 637 ​ $ 848 Warranty repairs ​ — ​ (3) ​ (25) ​ (94) Balance, end of the year ​ $ 612 ​ $ 754 ​ $ 612 ​ $ 754 ​ Segment information The Company determined its operating segment after considering the Company’s organizational structure and the information regularly reviewed and evaluated by the Company’s chief operating decision maker (“CODM”) in deciding how to allocate resources and assess performance. The Company has determined that its CODM is its Chief Executive Officer. The CODM reviews the financial information on a consolidated basis for purposes of evaluating financial performance and allocating resources. On the basis of these factors, the Company determined that it operates and manages its business as one operating segment, that develops, manufactures, markets and sells Systems and related LIMS connection software, consumables and services; and accordingly has one reportable segment for financial reporting purposes. Substantially all of the Company’s long-lived assets are held in the United States. Revenue recognition Remaining performance obligations The Company does not disclose the value of remaining performance obligations for (i) contracts with an original contract term of one year or less, (ii) contracts for which the Company recognizes revenue at the amount to which it has the right to invoice when that amount corresponds directly with the value of services performed, and (iii) Contract balances from contracts with customers Contract assets arise from unbilled amounts in customer arrangements when revenue recognized exceeds the amount billed to the customer and the Company’s right to payment is conditional and not only subject to the passage of time. The Company had $1.1 million and $0.5 million in contract assets as of September 30, 2021 and December 31, 2020, respectively, included in prepaid expenses and other current assets. These balances relate to the BARDA (as defined below) agreements, as well as unbilled amounts with commercial customers. Contract liabilities represent the Company’s obligation to transfer goods or services to a customer for which it has received consideration (or the amount is due) from the customer. The Company has a contract liability related to service revenue, which consists of amounts that have been invoiced but that have not been recognized as revenue. Amounts expected to be recognized as revenue within 12 months of the balance sheet date are classified as current deferred revenue and amounts expected to be recognized as revenue beyond 12 months of the balance sheet date are classified as noncurrent deferred revenue. The Company did not record any non-current deferred revenue as of September 30, 2021 or December 31, 2020. Deferred revenue was $3.9 million and $4.4 million at September 30, 2021 and December 31, 2020. Revenue recognized during the three months ended September 30, 2021 and 2020 that was included in deferred revenue at the prior period-end was $0.7 million and $0.2 million, respectively. Revenue recognized during the nine months ended September 30, 2021 and 2020 that was included in deferred revenue at the prior period-end was $3.6 million and $0.8 million, respectively. Non-commercial revenue The Company generates revenue from a long-term contract with the U.S. Department of Health and Human Services Biomedical Advanced Research and Development Authority (“BARDA”) a part of the U.S. government. The Company’s contracts with the U.S. government typically are subject to the Federal Acquisition Regulation (“FAR”) and are priced based on estimated or actual costs of producing goods or providing services. The FAR provides guidance on the types of costs that are allowable in establishing prices for goods or services provided under U.S. government contracts. In September 2017, the Company signed a contract with BARDA, which was subsequently modified on multiple occasions to increase the contract value and adjust the cost share reimbursement rate. Modifications were accounted for in accordance with the contract modification framework. The contract is a cost-reimbursable, cost- sharing arrangement, whereby BARDA reimburses the Company for a percentage of the total costs that have been incurred including indirect allowable costs. Revenue on the BARDA contract is recognized over time using an input method based on cost incurred to date in relation to total estimated cost. Due to the structure of the arrangement, the transaction price is variable in nature based on actual cost incurred. As such the amount included in the transaction price is constrained to the amount for which it is probable that a significant reversal of cumulative revenue recognized will not occur. Disaggregated revenue The Company disaggregates revenue based on the recurring and non-recurring, and commercial and non-commercial, nature of the underlying sale. Recurring revenue includes sales of consumables and service contracts. Non-recurring revenue includes sales of Systems, LIMS connection software, validation services, field service, and revenue under the Company’s contract with BARDA. The following table presents the Company’s revenue by the recurring or non-recurring and commercial or non-commercial nature of the revenue stream (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Product and service revenue — recurring ​ $ 2,171 ​ $ 855 ​ $ 5,539 ​ $ 2,712 Product and service revenue — non-recurring ​ 4,132 ​ 4,109 ​ 11,243 ​ 6,269 Non-commercial revenue — non-recurring ​ 596 ​ 283 ​ 1,242 ​ 1,858 Total revenue ​ $ 6,899 ​ $ 5,247 ​ $ 18,024 ​ $ 10,839 The following table presents the Company’s revenue by customer geography (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 United States ​ $ 4,313 ​ $ 2,067 ​ $ 10,086 ​ $ 4,401 Germany ​ 298 ​ 312 ​ 1,263 ​ 1,547 Switzerland ​ 899 ​ 2,765 ​ 2,989 ​ 3,574 All other countries ​ 1,389 ​ ​ 103 ​ ​ 3,686 ​ ​ 1,317 Total revenue ​ $ 6,899 ​ $ 5,247 ​ $ 18,024 ​ $ 10,839 ​ Advertising costs Advertising costs are expensed as incurred and are included in sales and marketing expenses in the condensed consolidated statements of operations. Advertising costs were less than $0.1 million during the three and nine months ended September 30, 2021 and 2020. Stock-based compensation The Company measures all stock-based awards granted to employees, officers and directors based on their fair value on the date of the grant and recognizes compensation expense for those awards over the requisite service period, which is generally the vesting period of the respective award. The Company issues stock-based awards with only service-based vesting conditions and records the expense for these awards using the straight-line method. Forfeitures are accounted for prospectively as they occur. The Company measures all restricted common stock granted to employees based on the common stock value on the date of grant. The purchase price of the restricted common stock is the common stock value on the date of grant. The restricted common stock includes a repurchase right, whereas upon the occurrence of a specific event, the Company shall have the right to repurchase unvested restricted common stock shares. At September 30, 2021 and December 31, 2020, the Company has $0.7 million and zero, respectively, in unvested restricted Class A common stock liability included in other long-term liabilities. Comprehensive loss Comprehensive loss includes net loss as well as other changes in stockholders’ deficit that result from transactions and economic events other than those with stockholders. For the three months ended September 30, 2021 and 2020, there were no other adjustments to comprehensive income or loss, and for the nine months ended September 30, 2021 and 2020, comprehensive loss included less than $0.1 million and zero, respectively, of unrealized gains on short-term investments, net of tax. Recently adopted accounting pronouncements I 2018, the FASB issued ASU No. 2018-15, Intangibles — Goodwill and Other — Internal-Use Software (Topic 35): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement that is a Service Contract, which requires capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The Company adopted this guidance effective on January 1, 2021 and adoption did not have a material impact on the condensed consolidated financial statements and related disclosures. Recently issued accounting pronouncements The Company qualifies as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 and has elected not to “opt out” of the extended transition related to complying with new or revised accounting standards, which means that when a standard is issued or revised and it has different application dates for public and nonpublic companies, the Company will adopt the newer revised standard at the time nonpublic companies adopt the new or revised standard and will do so until such time that the Company either (i) irrevocably elects to “opt out” of such extended transition period or (ii) no longer qualifies as an emerging growth company. The Company may choose to early adopt any new or revised accounting standards whenever such early adoption is permitted for nonpublic companies. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments — Credit Losses (Topic 326) In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e., lessees and lessors). The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. Leases with a term of 12 months or less may be accounted for similar to existing guidance for operating leases today. For public business entities, ASU 2016-02 is effective for annual reporting periods beginning after December 15, 2018, including interim periods within those fiscal years, and early adoption is permitted. For nonpublic entities, this guidance is effective for annual periods beginning after December 15, 2021. The Company expects to adopt this guidance effective January 1, 2022, and it is currently evaluating the impact on its condensed consolidated financial statements and related disclosures. In December 2019, the FASB issued ASU 2019-12, Income Taxes (ASC 740): Simplifying the Accounting for Income Taxes

Fair value of financial assets

Fair value of financial assets and liabilities	9 Months Ended
	Sep. 30, 2021
Fair value of financial assets and liabilities
Fair value of financial assets and liabilities	3. Fair value of financial assets and liabilities The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy used to determine such fair values (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value measurements as of September 30, 2021 ​ Level 1 Level 2 Level 3 Total Assets ​ ​ ​ ​ ​ Cash equivalents ​ $ 212,833 ​ $ — ​ $ — ​ $ 212,833 ​ ​ $ 212,833 ​ $ — ​ $ — ​ $ 212,833 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value measurements at December 31, 2020 ​ Level 1 Level 2 Level 3 Total Assets ​ ​ ​ ​ ​ Cash equivalents ​ $ 23,456 ​ $ — ​ $ — ​ $ 23,456 Short-term investments ​ 14,998 ​ — ​ — ​ 14,998 ​ ​ $ 38,454 ​ $ — ​ $ — ​ $ 38,454 Liabilities ​ ​ ​ ​ ​ Preferred stock warrant liability ​ $ — ​ $ — ​ $ 4,117 ​ $ 4,117 ​ ​ $ — ​ $ — ​ $ 4,117 ​ $ 4,117 ​ During the three and nine months ended September 30, 2021 and 2020, respectively, there were no transfers between Level 1, Level 2 and Level 3. Valuation of short-term investments Short-term investments, which consisted of U.S. Treasury bonds were valued by the Company using quoted prices in active markets for similar securities, which represents a Level 1 measurement within the fair value hierarchy. Valuation of preferred stock warrant liability The warrant liability was related to the warrants (the “Warrants”) to purchase shares of the Company’s Series A1, B1, and C1 redeemable convertible preferred stock (see Note 11). The fair value of the warrant liability was determined based on inputs not observable in the market, which represents a Level 3 measurement within the fair value hierarchy. The Company used the Black-Scholes option-pricing model, which incorporates assumptions and estimates, to value the warrant liability. Key estimates and assumptions impacting the fair value measurement include (i) the fair value per share of the underlying shares of applicable series of redeemable convertible preferred stock issuable upon exercise of the Warrants, (ii) the remaining contractual term of the Warrants, (iii) the risk-free interest rate, (iv) the expected dividend yield and (iv) expected volatility of the price of the underlying applicable series of redeemable convertible preferred stock. The Company estimated the fair value per share of the underlying applicable series of redeemable convertible preferred stock based, in part, on the results of third-party valuations and additional factors deemed relevant. The risk-free interest rate was determined by reference to the U.S. Treasury yield curve for time periods approximately equal to the remaining contractual term of the Warrant. The Company estimated a zero expected dividend yield based on the fact that the Company has never paid or declared dividends and does not intend to do so in the foreseeable future. As the Company has historically been a private company and lacks company-specific historical and implied volatility information of its stock, the expected stock volatility was based on the historical volatility of publicly traded peer companies for a term equal to the remaining contractual term of the Warrant. In connection with the IPO, all of the Company’s outstanding preferred stock warrants were automatically converted to Class A common stock warrants. The Company performed a final fair value assessment of these warrants as of the date of its IPO which resulted in a charge of $8.2 million that was recorded within other income (expense) in the Company’s condensed consolidated statement of operations. The Company determined the conversion to Class A common stock warrants resulted in equity classification of the Class A common stock warrants and reclassified the fair value of the preferred stock warrant liability as of the IPO date into stockholders’ equity (see Note 12). The table below quantifies the weighted average of the unobservable inputs used to fair value the preferred stock warrant liability prior to their conversion into common stock warrants: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Fair value of Series A1 preferred stock ​ $ 4.00 ​ $ 0.39 ​ ​ $ 3.01 ​ $ 0.45 ​ Fair value of Series B1 preferred stock ​ $ 4.00 ​ $ 1.17 ​ ​ $ 3.26 ​ $ 1.13 ​ Fair value of Series C1 preferred stock ​ $ 4.00 ​ $ 1.15 ​ ​ $ 3.30 ​ $ 1.15 ​ Remaining contractual term (in years) ​ 6.6 ​ 7.4 ​ ​ 6.8 ​ 7.7 ​ Risk-free interest rate ​ 1.0 % 0.6 % ​ 1.2 % 0.6 % Expected dividend yield ​ — % — % ​ — % — % Expected volatility ​ 42.2 % 40.3 % ​ 42.0 % 39.3 % ​ The following table provides a rollforward of the aggregate fair values of the Company’s preferred stock warrant liability, for which fair values are determined using Level 3 inputs (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Balance, beginning of period ​ $ 15,600 ​ $ 3,499 ​ $ 4,117 ​ $ 3,396 Initial fair value of Series C1 preferred stock warrants ​ ​ — ​ ​ — ​ ​ — ​ ​ 652 Change in fair value of preferred stock warrants ​ 8,160 ​ — ​ 19,643 ​ (549) Conversion of preferred stock warrants to common stock warrants ​ (23,760) ​ — ​ (23,760) ​ — Balance, end of period ​ $ — ​ $ 3,499 ​ $ — ​ $ 3,499 ​

Short-term investments

Short-term investments	9 Months Ended
	Sep. 30, 2021
Short-term investments
Short-term investments	4. Short-term investments Short-term investments by investment type consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ Amortized unrealized unrealized Fair ​ cost gains losses value U.S. Treasury bonds ​ $ 14,997 ​ $ 1 ​ $ — ​ $ 14,998 ​ ​ $ 14,997 ​ $ 1 ​ $ — ​ $ 14,998 ​ The Company did not have short-term investments at September 30, 2021.

Inventory

Inventory	9 Months Ended
	Sep. 30, 2021
Inventory
Inventory	5. Inventory Inventory consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2021 2020 Raw materials ​ $ 10,315 ​ $ 6,754 Work in process ​ 689 ​ 1,190 Finished goods ​ 3,163 ​ 1,021 Total ​ $ 14,167 ​ $ 8,965 ​ Raw materials, work in process and finished goods were net of adjustments to net realizable value.

Prepaid expenses and other curr

Prepaid expenses and other current assets	9 Months Ended
	Sep. 30, 2021
Prepaid expenses and other current assets
Prepaid expenses and other current assets	6. Prepaid expenses and other current assets Prepaid expenses and other current assets consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2021 2020 Prepaid insurance ​ $ 2,621 ​ $ 355 Prepaid commitment fee on notes payable ​ ​ — ​ ​ 275 Contract asset ​ 1,065 ​ 471 Deposits ​ 1,415 ​ 1,148 Lease receivables, current portion ​ 282 ​ 325 Other ​ 17 ​ 546 ​ ​ $ 5,400 ​ $ 3,120 ​

Property and equipment, net

Property and equipment, net	9 Months Ended
	Sep. 30, 2021
Property and equipment, net
Property and equipment, net	7. Property and equipment, net Property and equipment, net consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2021 2020 Manufacturing and laboratory equipment ​ $ 13,198 ​ $ 12,961 Computer hardware and software ​ 1,637 ​ 1,088 Office furniture and fixtures ​ 723 ​ 343 Leasehold improvements ​ ​ 3,012 ​ ​ 2,996 Construction-in-process ​ 1,454 ​ — ​ ​ 20,024 ​ 17,388 Less: Accumulated depreciation ​ (11,391) ​ (10,336) ​ ​ $ 8,633 ​ $ 7,052 ​ As of September 30, 2021 and December 31, 2020, the Company's office furniture and fixtures shown in the above table included assets under a capital lease in the amount of $0.4 million and zero, respectively, and accumulated depreciation of less than $0.1 million and zero as of September 30, 2021 and December 31, 2020, respectively. As of September 30, 2021, future minimum lease payments under the capital lease were $0.6 million, with $0.2 million representing interest. The capital lease obligation is recorded in other long-term liabilities within the consolidated balance sheet.

Accrued expenses and other curr

Accrued expenses and other current liabilities	9 Months Ended
	Sep. 30, 2021
Accrued expenses and other current liabilities
Accrued expenses and other current liabilities	8. Accrued expenses and other current liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2021 2020 Accrued employee compensation and benefits expense ​ $ 3,500 ​ $ 3,083 Accrued vendor expenses ​ 5,885 ​ 1,685 Accrued warranty expense ​ 612 ​ 637 Accrued interest ​ — ​ 330 Deferred rent, current portion ​ 127 ​ 118 Accrued taxes ​ 748 ​ 688 Other ​ 694 ​ 113 ​ ​ $ 11,566 ​ $ 6,654 ​

Long-term debt

Long-term debt	9 Months Ended
	Sep. 30, 2021
Long-term debt
Long-term debt	9. Long-term debt The components of the Company’s long-term debt consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2021 2020 Notes payable ​ $ — ​ $ 25,000 Payment in kind interest ​ — ​ 1,145 Less: Unamortized discount ​ — ​ (1,335) Long-term debt, net of discount ​ $ — ​ $ 24,810 ​ Term loan agreements 2018 Term Loan In April 2018, the Company entered into an $18.0 million term loan with a lender (the “2018 Term Loan”). The Company repaid the 2018 Term Loan in full in May 2020 using the proceeds from the 2020 Term Loan as discussed below. The Company paid $19.4 million to extinguish the outstanding principal and accrued interest owed, including the non-refundable end-of-term exit fee of $1.3 million (out of which $0.6 million was accrued for in prior years as interest expense) and an early termination fee of $0.1 million. The loss on extinguishment of debt was $2.9 million which included the write-off of unamortized financing and end-of-term exit fee costs of $0.7 million and $0.1 million in early payment and documentation fees, and was included as a component of other income (expense) in the condensed consolidated statements of operations during the nine months ended September 30, 2020. Interest expense on the 2018 Term Loan totaled less than $0.1 million and $0.8 million for three and nine months ended September 30, 2020, respectively, which includes amortization of the debt discount of less than $0.1 million and $0.2 million during the three and nine months ended September 30, 2020, respectively. 2020 Term Loan In May 2020, the Company entered into a $60.0 million term loan facility with a new lender (the “2020 Term Loan”), which provides for borrowings of an initial $25.0 million tranche upon closing and options to borrow up to an aggregate of $35.0 million in two additional tranches of $20.0 million under the second tranche (the “Term B Loan”) and $15.0 million under the third tranche (the “Term C Loan”). At closing, the Company issued warrants to purchase 1,195,652 shares of Series C1 Preferred Stock to the lender with an exercise price of $1.15 per share which were accounted for as debt discount. The Company paid a $0.8 million facility fee in connection with the term loan facility. The Company allocated the $0.8 million term loan facility fee to the three loan tranches on a pro-rata basis based on the amount available to be drawn down under each tranche. The Company allocated $0.3 million to the initial draw which was recorded within debt issuance cost as an offset to the carrying value of the 2020 Term Loan and amortized over the term of the loan within interest expense on the condensed consolidated statement of operations. Additionally, the Company allocated $0.3 million to the Term B Loan and $0.2 million to the Term C Loan, all of which was recorded within prepaid expenses and other current assets on the consolidated balance sheet and is being amortized on a straight-line basis over the debt access period within interest expense on the consolidated statement of operations. The Company incurred debt issuance costs of $1.5 million in connection with the 2020 Term Loan including $0.9 million of professional fees and $0.6 million for the fair value of the warrants issued with the debt. Interest expense on the 2020 Term Loan totaled $0.7 million and $2.5 million for the three and nine months ended September 30, 2021, respectively, which includes amortization of the debt discount of less than $0.1 million and $0.3 million during the three and nine months ended September 30, 2021, respectively In September 2021, the Company repaid the 2020 Term Loan and incurred a debt extinguishment loss of $3.1 million, which was comprised of a $1.8 million prepayment penalty, $1.1 million expense related to unamortized discounts, and $0.2 million in unamortized prepaid facility fees and other charges. As of September 30, 2021, the Company had no outstanding balance on the 2020 Term Loan. Convertible Notes In February 2020, the Company issued Convertible Notes to several investors in the aggregate amount of $9.5 million with a stated interest rate of 1.5% per annum and a maturity date of February 28, 2021. The Convertible Notes provided a conversion option whereby upon the closing of a financing event, in which the aggregate gross proceeds of the issuance of preferred stock totaled at least $20.0 million, the notes would automatically convert into shares of the same class and series of capital stock of the Company issued to other investors in the financing at a conversion price equal to 80% of the price per share paid by the other investors. The conversion option met the definition of an embedded derivative and was required to be bifurcated and accounted for separately from the notes. The proceeds from the Convertible Notes were allocated between the derivative liability, with a fair value at issuance of $2.4 million, and the notes, with an initial carrying value of $7.1 million, included in long-term liabilities on the Company’s condensed consolidated balance sheets. The difference between the initial carrying value of the notes and the stated value of the notes represented a discount and that was accreted to interest expense over the term of the Convertible Notes using the effective interest method. In April 2020, the Convertible Notes, including outstanding principal and accrued interest totaling $9.5 million, were automatically converted into 10,351,063 shares of Series C1 Preferred Stock. Upon conversion, the remaining unamortized discount was recognized as loss on extinguishment of debt in the condensed consolidated statement of operations. Interest expense on the Convertible Notes was zero and $0.4 million for the three and nine months ended September 30, 2020, respectively, which consists primarily of amortization of the debt discount.

Redeemable convertible preferre

Redeemable convertible preferred stock	9 Months Ended
	Sep. 30, 2021
Redeemable convertible preferred stock.
Redeemable convertible preferred stock	10. Redeemable convertible preferred stock The Company has issued Series A1 redeemable convertible preferred stock (the “Series A1 Preferred Stock”), Series B1 redeemable convertible preferred stock (the “Series B1 Preferred Stock”), Series C1 redeemable convertible preferred stock (the “Series C1 Preferred Stock”), Series C2 redeemable convertible preferred stock (the “Series C2 Preferred Stock”), Series D1 redeemable convertible preferred stock (the “Series D1 Preferred Stock”) and Series D2 redeemable convertible preferred stock (the “Series D2 Preferred Stock”). The Series A1 Preferred Stock, Series B1 Preferred Stock, Series C1 Preferred Stock, Series C2 Preferred Stock, Series D1 Preferred Stock, and Series D2 Preferred Stock are collectively referred to as the “Preferred Stock”. In April 2020, the Company issued and sold 23,611,208 shares of Series C1 Preferred Stock and 20,301,829 shares of Series C2 Preferred Stock to new and existing investors at a price of $1.15 per share for gross proceeds of $27.2 million and $23.3 million, respectively. Additionally, the Company’s Convertible Notes, including outstanding principal and accrued interest totaling $9.5 million (see Note 9), were automatically converted into 10,351,063 shares of Series C1 Preferred Stock. The Company incurred issuance costs in connection with this transaction of $0.6 million and recorded them as a reduction to the carrying value of the Series C1 Preferred Stock and Series C2 Preferred Stock. In March 2021, the Company issued and sold 22,086,725 shares of Series D1 Preferred Stock and 413,268 shares of Series D2 Preferred Stock to new and existing investors at a price of $3.60 per share for gross proceeds of $79.5 million and $1.5 million, respectively. The Company incurred issuance costs in connection with this transaction of $2.7 million and recorded them as a reduction to the carrying value of the Series D1 Preferred Stock and Series D2 Preferred Stock. On June 25, 2021, investors exchanged a total of 11,437,301 shares and 2,364,509 shares of Series C1 and D1 Preferred Stock to an equal number of shares of Series C2 and D2 Preferred Stock, respectively. On July 14, 2021, the IPO resulted in the automatic conversion Series A1, Series B1, Series C1 and Series D1 preferred stock to 24,200,920 shares of Class A common stock and Series C2 and Series D2 converted into 6,903,379 shares of Class B common stock. On July 19, 2021, the Company restated its certificate of incorporation and authorized 10,000,000 shares of $0.01 par value Preferred Stock. As As of December 31, 2020, Preferred Stock consisted of the following (in thousands, except for share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ Preferred stock ​ ​ ​ ​ ​ ​ Common stock ​ Preferred stock issued and ​ Liquidation issuable upon ​ authorized outstanding Carrying value preference conversion Series A1 Preferred Stock ​ 22,563,639 ​ 18,740,115 ​ $ 18,542 ​ $ 21,176 ​ 3,748,022 Series B1 Preferred Stock ​ 61,217,425 ​ 60,017,425 ​ ​ 68,511 ​ ​ 90,026 ​ 12,003,474 Series C1 Preferred Stock ​ 57,372,796 ​ 33,962,271 ​ ​ 40,632 ​ ​ 58,585 ​ 6,792,445 Series C2 Preferred Stock 20,301,829 20,301,829 ​ 24,141 ​ 35,021 4,060,365 ​ 161,455,689 133,021,640 ​ $ 151,826 ​ $ 204,808 26,604,306 ​

Preferred stock warrants

Preferred stock warrants	9 Months Ended
	Sep. 30, 2021
Preferred stock warrants
Preferred stock warrants	11. In connection with the 2020 Term Loan, the Company issued 1,195,652 warrants to purchase shares of Series C1 Preferred Stock at an exercise price of $1.15 per share. The Company’s warrants were immediately exercisable and expire 10 years after issuance. The fair value of the warrants on the issuance date was $0.7 million. The Company also has outstanding warrants to purchase shares of Preferred Stock issued in connection with previous financing agreements. In connection with the IPO, preferred stock warrants were automatically converted to Class A common stock warrants. The Company determined the event resulted in equity classification of the Class A common stock warrants and reclassified the fair value of the preferred stock warrant liability as of the IPO date into equity. As of December 31, 2020, warrants to purchase the following classes of preferred stock outstanding consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ Series of ​ ​ ​ Preferred ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ redeemable ​ ​ ​ shares ​ Weighted ​ ​ ​ ​ ​ Contractual ​ convertible ​ ​ ​ issuable upon ​ average ​ ​ ​ ​ ​ term ​ preferred ​ Balance sheet ​ exercise ​ exercise ​ Warrant fair Issuance date (in years) stock classification of warrant price value April 24, 2017 10 Series A1 Liability 3,823,524 ​ $ 0.01 ​ $ 1,875 April 12, 2018 10 Series B1 Liability 1,199,994 ​ $ 0.01 ​ 1,501 May 14, 2020 10 Series C1 Liability 1,195,652 ​ $ 1.15 ​ 741 ​ ​ ​ ​ ​ ​ ​ 6,219,170 ​ ​ ​ ​ $ 4,117 ​

Common stock and common stock w

Common stock and common stock warrants	9 Months Ended
	Sep. 30, 2021
Common stock and common stock warrants
Common stock and common stock warrants	12. As of September 30, 2021 and December 31, 2020, the Company’s restated certificate of incorporation authorized the issuance of 210,000,000 shares and 35,000,000 shares, respectively, of $0.01 par value Class A common stock. On June 25, 2021, the Company filed an amended and restated certificate of incorporation, which effected a recapitalization of the Company’s then outstanding common stock to Class A common stock and authorized an additional new class of common stock (Class B common stock). Rights of the holders of Class A common stock and Class B common stock are identical, except with respect to voting and conversion. On July 19, 2021, the Company filed an amended and restated certificate of incorporation which authorized Class A common stock and Class B common stock to 210,000,000 shares and 10,000,000 shares, respectively. As of September 30, 2021, there were outstanding outstanding Each share of Class A common stock entitles the holder to one vote on all matters submitted to a vote of the Company’s stockholders. The Company’s Class B common stock is non-voting. Class A and Class B common stockholders are entitled to receive dividends, as may be declared by the board of directors, if any, subject to the preferential dividend rights of Preferred Stock. As of September 30, 2021 and December 31, 2020, no cash dividends had been declared or paid. As of September 30, 2021 and December 31, 2020, the Company had reserved 9,991,141 and 32,574,029 shares, respectively, of common stock for the conversion of the outstanding Preferred Stock (see Note 10), exercise of outstanding stock options, the number of shares remaining available for grant under the Company’s 2010 Stock Incentive Plan and 2021 Incentive Award Plan (see Note 13) and the exercise of outstanding warrants to purchase shares of preferred stock (see Note 11) and Class A common stock. In prior years the Company issued warrants to purchase common stock in conjunction with previous financing arrangements. In connection with the IPO, preferred stock warrants were automatically converted to Class A common stock warrants. The contractual term of the converted Class A common stock warrants remained consistent with the original term of the preferred stock warrants. The Company determined the event resulted in equity classification of the Class A common stock warrants and reclassified the fair value of the preferred stock warrant liability as of the IPO date into equity. ​ As of September 30, 2021, outstanding warrants to purchase common stock consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2021 ​ ​ ​ ​ Shares of ​ ​ ​ ​ ​ ​ ​ ​ common stock ​ ​ ​ ​ ​ ​ ​ Balance sheet ​ issuable upon ​ Weighted average Issuance date Contractual term classification exercise of warrant exercise price ​ ​ (in years) ​ ​ ​ ​ ​ ​ ​ July 24, 2017 ​ 10 ​ Equity ​ 25,835 ​ $ 295.15 April 12, 2018 ​ 10 ​ Equity ​ 30,000 ​ $ 1.00 July 14, 2021 ​ 10 ​ Equity ​ 975,109 ​ $ 1.46 ​ ​ ​ ​ ​ ​ 1,030,944 ​ ​ ​ ​ As of December 31, 2020, outstanding warrants to purchase common stock outstanding consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ Shares of ​ ​ ​ ​ ​ ​ ​ ​ common stock ​ ​ ​ ​ ​ ​ ​ Balance sheet ​ issuable upon ​ Weighted average Issuance date Contractual term classification exercise of warrant exercise price ​ ​ (in years) ​ ​ ​ ​ ​ ​ ​ July 24, 2017 ​ 10 ​ Equity ​ 25,835 ​ $ 295.15 April 12, 2018 ​ 10 ​ Equity ​ 30,000 ​ $ 1.00 ​ ​ ​ ​ ​ ​ 55,835 ​ ​ ​ ​

Stock-based compensation

Stock-based compensation	9 Months Ended
	Sep. 30, 2021
Stock-based compensation
Stock-based compensation	13. Stock-based compensation 2010 Stock Option and Grant Plan At December 31, 2020, a total of 4,945,783 shares of common stock were reserved for issuance under the 2010 Plan. In March 2021, the Board of Directors approved an increase to the 2010 Plan shares by 382,889 shares. Upon the effectiveness of the IPO, no additional awards will be granted under the 2010 Plan and shares of existing outstanding options that are returned will be returned and can be granted under the 2021 Incentive Award Plan (described below). 2021 Incentive Award Plan In July 2021, the Board of Directors adopted, and the Company’s stockholders approved, the 2021 Incentive Award Plan (the “2021 Plan”), which became effective in connection with the IPO of Class A common stock. The 2021 Plan provides for the grant of stock options, including incentive stock options and non-qualified stock options, stock appreciation rights, restricted stock, restricted stock units, and other stock-based and cash-based awards. The 2021 Plan has a term of . The aggregate number of shares of Class A common stock available for issuance under the 2021 Plan is equal to (i) of the aggregate number of shares of Class A common stock outstanding on the last day of the immediately preceding calendar year and (B) such smaller amount of shares as determined by the Board of Directors. No more than shares of Class A common stock may be issued under the 2021 Plan upon the exercise of incentive stock options. As of September 30, 2021, there are The following table presents, on a weighted average basis, the assumptions used in the Black-Scholes option-pricing model to determine the grant-date fair value of stock options granted to employees and directors: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, ​ Nine Months Ended September 30, ​ 2021 2020 2021 2020 Risk-free interest rate 0.96 % 0.34 % 0.90 % 0.36 % Expected term (in years) 5.8 6.0 ​ 6.0 6.0 ​ Expected volatility 43.7 % 90.4 % 51.5 % 90.3 % Expected dividend yield 0 % 0 % 0 % 0 % ​ Stock options The following table summarizes the Company’s stock option activity since December 31, 2020 (in thousands, except for share and per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ​ average ​ ​ ​ ​ Number of ​ average ​ remaining ​ Aggregate ​ shares exercise price contractual term intrinsic value ​ ​ ​ ​ ​ ​ ​ (in years) ​ ​ ​ Outstanding as of December 31, 2020 3,604,584 ​ $ 0.92 8.12 ​ $ 4,272 Granted 1,732,182 ​ 9.15 ​ ​ ​ ​ ​ Exercised (111,149) ​ 2.67 ​ Expired (34,447) ​ 1.00 ​ Forfeited (667,866) ​ 2.12 ​ Outstanding as of September 30, 2021 4,523,304 ​ $ 3.88 7.68 ​ $ 66,231 Options vested and expected to vest as of September 30, 2021 4,523,304 ​ $ 3.88 7.68 ​ $ 66,231 Options exercisable as of September 30, 2021 2,134,381 ​ $ 1.25 6.17 ​ $ 36,777 ​ The aggregate intrinsic value of options is calculated as the difference between the exercise price of the stock options and the fair value of the Company’s common stock (or Class A common stock as of September 30, 2021) for those options that had exercise prices lower than such fair value. The intrinsic value of stock options exercised during the nine months ended September 30, 2021 and 2020 was $0.4 million and zero, respectively. The weighted average grant-date fair value per share of stock options granted during the three months ended September 30, 2021 and 2020 was $8.33 and $0.55, respectively, and during the nine months ended September 30, 2021 and 2020 was $4.05 and $0.55, respectively. Restricted stock In February 2021, the Company granted 248,903 shares of restricted stock to an employee under the 2010 Plan with a four-year vesting term. In connection with the grant, the employee paid $0.5 million, which represents the $2.10 per share fair value of the common stock on the date of the restricted stock grant. The restricted common stock includes a repurchase right, whereas upon the occurrence of the employee’s resignation or termination for cause or good reason the Company shall have the right to repurchase unvested restricted common stock shares. At September 30, 2021 and December 31, 2020, the Company has $0.7 million and zero in unvested restricted common stock liability included in other long-term liabilities, respectively. The following table summarizes the Company’s restricted stock activity since December 31, 2020 (in thousands except for share and per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ Number of ​ average ​ shares fair value ​ ​ ​ ​ (in years) Unvested as of December 31, 2020 ​ - ​ ​ ​ Granted ​ 248,903 ​ $ 2.10 Vested ​ - ​ ​ ​ Forfeited ​ - ​ ​ ​ Unvested as of September 30, 2021 ​ 248,903 ​ $ 2.10 ​ 2021 Employee Stock Purchase Plan In July 2021, the Board of Directors adopted, and the Company’s stockholders approved, the 2021 Employee Stock Purchase Plan (the “2021 ESPP”), which became effective in connection with the IPO of Class A common stock. The aggregate number of shares of Class A common stock available for issuance under the 2021 ESPP is equal to (i) 400,000 shares and (ii) an annual increase for ten years on the first day of each calendar year beginning on January 1, 2022, equal to the lesser of (A) 1% of the aggregate number of shares of Class A common stock outstanding on the last day of the immediately preceding calendar year and (B) such smaller amount of shares as determined by the Board of Directors. No more than 6,300,000 shares of Class A common stock may be issued under the 2021 ESPP. As of September 30, 2021, no offering periods have been initiated. Stock-based compensation expense Stock-based compensation expense was classified in the condensed consolidated statements of operations as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Cost of revenue ​ $ 106 ​ $ 20 ​ $ 221 ​ $ 62 General and administrative ​ 345 ​ 72 ​ 680 ​ 223 Sales and marketing ​ 76 ​ 11 ​ 158 ​ 42 Research and development ​ 57 ​ 12 ​ 106 ​ 34 Total stock-based compensation expense ​ $ 584 ​ $ 115 ​ $ 1,165 ​ $ 361 ​ As of September 30, 2021, total unrecognized compensation expense related to unvested stock options held by employees and directors was $6.2 million, which is expected to be recognized over a weighted average period of 1.4 years.

Income taxes

Income taxes	9 Months Ended
	Sep. 30, 2021
Income taxes
Income taxes	14. Income taxes During the three and nine months ended September 30, 2021 and 2020, the pretax losses incurred by the Company, as well as the research and development tax credits generated, received no corresponding tax benefit because the Company concluded that it is more likely than not that the Company will be unable to realize the value of any resulting deferred tax assets. The Company will continue to assess its position in future periods to determine if it is appropriate to reduce a portion of its valuation allowance in the future. The Company’s tax provision and the resulting effective tax rate for interim periods is determined based upon its estimated annual effective tax rate (“AETR”), adjusted for the effect of discrete items arising in that quarter. The impact of such inclusions could result in a higher or lower effective tax rate during a particular quarter, based upon the mix and timing of actual earnings or losses versus annual projections. In each quarter, the Company updates its estimate of the annual effective tax rate, and if the estimated annual tax rate changes, a cumulative adjustment is made in that quarter. The Company has evaluated the positive and negative evidence bearing upon its ability to realize its deferred tax assets, which primarily consist of net operating loss carryforwards. The Company has considered its history of cumulative net losses, estimated future taxable income and prudent and feasible tax planning strategies and has concluded that it is more likely than not that the Company will not realize the benefits of its deferred tax assets. As a result, as of September 30, 2021 and December 31, 2020 the Company has recorded a full valuation allowance against its net deferred tax assets. The Company files U.S. income tax returns as prescribed by the tax laws of the jurisdictions in which it operates. In the normal course of business, the Company is subject to examination by federal and state jurisdictions, where applicable. There are currently no pending tax examinations in the U.S. The Company has not received notice of examination by any jurisdictions in the U.S. The Company has a branch in Germany that is under examination in its local country for tax years 2016-2018. Any adjustments that may result from the examinations are not expected to have a material impact on the financial position, liquidity, or results of operations of the Company.

Net loss per share

Net loss per share	9 Months Ended
	Sep. 30, 2021
Net loss per share
Net loss per share	15. Net loss per share Net loss per share attributable to common stockholders. As of September 30, 2021, the Company has Class A common stock and Class B common stock. According to the Company’s restated certificate of incorporation, both classes have the same rights to the Company’s earnings and neither of the shares have any prior or senior rights to dividends to other shares. The Company reported a net loss attributable to common stockholders for the three and nine months ended September 30, 2021 and 2020, as such basic net loss per share attributable to common stockholders was the same as diluted net loss per share attributable to common stockholders. Basic and diluted net loss per share attributable to common stockholders was calculated as follows (in thousands, except share and per share amounts): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ Net loss ​ $ (24,987) ​ $ (8,465) ​ $ (58,919) ​ $ (25,739) Accretion of redeemable convertible preferred stock to redemption value ​ 210 ​ (832) ​ (1,761) ​ (2,882) Cumulative redeemable convertible preferred stock dividends ​ (451) ​ (1,412) ​ (2,747) ​ (2,987) Net loss attributable to common stockholders—basic and diluted ​ $ (25,228) ​ $ (10,709) ​ $ (63,427) ​ $ (31,608) Denominator: ​ ​ ​ ​ Weighted average Class A common shares outstanding—basic and diluted ​ ​ 29,463,234 ​ ​ 356,074 ​ ​ 10,372,225 ​ ​ 354,341 Weighted average Class B common shares outstanding—basic and diluted ​ ​ 5,852,865 ​ ​ — ​ ​ 1,972,394 ​ ​ — Total shares for EPS—basic and diluted ​ ​ 35,316,099 ​ ​ 356,074 ​ ​ 12,344,619 ​ ​ 354,341 Net loss per share attributable to Class A common stockholders—basic and diluted ​ ​ (0.71) ​ ​ (30.08) ​ ​ (5.14) ​ ​ (89.20) Net loss per share attributable to Class B common stockholders—basic and diluted ​ (0.71) ​ — ​ (5.14) ​ — ​ The Company’s potentially dilutive securities, which include stock options, redeemable convertible preferred stock, common stock warrants and preferred stock warrants, have been excluded from the computation of diluted net loss per share as the effect would be to reduce the net loss per share. Therefore, the weighted average number of common shares outstanding used to calculate both basic and diluted net loss per share attributable to common stockholders is the same. The Company excluded the following potential common shares, presented based on amounts outstanding at each period end, from the computation of diluted net loss per share attributable to common stockholders for the periods indicated because including them would have had an anti-dilutive effect: ​ ​ ​ ​ ​ ​ ​ September 30, ​ 2021 2020 Options to purchase common stock 4,772,207 4,005,581 Warrants to purchase common stock 294,965 55,872 Redeemable convertible preferred stock (as converted to common stock) — 26,604,306 Warrants to purchase preferred stock (as converted to warrants to purchase common stock) — 1,243,834 ​ 5,067,172 31,909,593 ​

Commitments and contingencies

Commitments and contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and contingencies
Commitments and contingencies	16. Commitments and contingencies Lease agreements In October 2013, the Company entered into an operating lease for office and manufacturing space in Lowell, Massachusetts, which expires in July 2026. The terms of the lease include options for early termination of the lease in July 2024 and a one-time, five-year extension of the lease following its expiration as well as a $0.7 million tenant improvement allowance, which was fully utilized as of September 30, 2021. In June 2021, the Company entered into a Sublease agreement for office and manufacturing space in Lexington, Massachusetts, which expires in June 2029. The Sublease agreement includes an option to terminate the sublease in July 2026, subject to an early termination fee. The Company also has the right to use furniture and equipment specified in the Sublease agreement for $0.6 million in future payments over the term of the sublease with the option to purchase the furniture and equipment at the end of the sublease term. Additionally, the Sublease requires the Company to return part of the leased space back to its original condition upon termination. As a result, the Company recognized an asset retirement obligation in the amount of $0.2 million which is classified in other long-term liabilities within the consolidated balance sheet. Concurrent with entering into the Sublease agreement, the Company executed an Option Agreement with the property owner which provides the Company the option to enter into a new direct lease for the Lexington facility for an additional five years following expiration of the sublease. The Company recognizes rent expense on a straight-line basis over the respective lease period. The Company has recorded deferred rent for rent expense incurred but not yet paid. Rent expense was $0.2 million and $0.1 million for the three months ended September 30, 2021 and 2020, respectively, and rent expense was $0.4 million and $0.3 million for the nine months ended September 30, 2021 and 2020, respectively. Future minimum lease commitments under operating leases as of September 30, 2021 are as follows (in thousands): ​ ​ ​ ​ Year ending December 31, ​ 2021 ​ $ 169 2022 ​ 1,139 2023 ​ 1,169 2024 ​ 1,199 2025 ​ 1,229 Thereafter ​ 2,997 Total ​ $ 7,902 ​ Exit fee In December 2016, in connection with the amendment of a then-outstanding loan agreement with the lender, the Company entered into an agreement under which it was obligated to pay the lender an exit fee in the amount of $0.8 million in the event of a qualifying exit event prior to December 31, 2026. A qualifying event was defined as any (i) liquidation, dissolution or winding up whether voluntary or involuntary; (ii) consolidation, merger or reverse merger; (iii) sale, lease, transfer, exclusive license, exchange, dividend or other disposition of all or substantially all of the Company’s assets; (iv) issuance and/or sale of the Company’s stock that is greater than 50% of the shares of common stock immediately following such issuance; (v) any other form of acquisition or business combination that results in a change of control at the Company; or (vi) the consummation of any public offering of shares of common stock. There were no amounts accrued for the exit fee at December 31, 2020, as the occurrence of a qualifying exit event was not deemed probable. The Company paid the exit fee following the IPO, which was considered a qualifying event. The exit fee expense is included in Other income (expense) on the condensed consolidated statements of operations for the three and nine months ended September 30, 2021. Supply agreement Software subscription During the year ended December 31, 2020, the Company entered into a non-cancelable agreement with a service provider for software as a service and cloud hosting services. As of September 30, 2021, the Company had committed to minimum payments under these arrangements totaling $1.1 million through January 31, 2026. The Company accrues a liability for such matters when it is probable that future expenditures will be made and such expenditures can be reasonably estimated. There were no amounts accrued for the software subscription as of September 30, 2021 and December 31, 2020. Indemnification agreements In the ordinary course of business, the Company may provide indemnification of varying scope and terms to customers, vendors, lessors, business partners and other parties with respect to certain matters including, but not limited to, losses arising out of breach of such agreements or from intellectual property infringement claims made by third parties. In addition, the Company has entered into indemnification agreements with members of its board of directors and certain of its executive officers that will require the Company, among other things, to indemnify them against certain liabilities that may arise by reason of their status or service as directors or officers. The maximum potential amount of future payments the Company could be required to make under these indemnification agreements is, in many cases, unlimited. To date, the Company has not incurred any material costs as a result of such indemnifications. The Company is not currently aware of any indemnification claims and has not accrued any liabilities related to such obligations in its condensed consolidated financial statements as of September 30, 2021 and December 31, 2020. Legal proceedings The Company is not a party to any litigation and does not have contingency reserves established for any litigation liabilities. At each reporting date, the Company evaluates whether or not a potential loss amount or a potential range of loss is probable and reasonably estimable under the provisions of the authoritative guidance that addresses accounting for contingencies. The Company expenses as incurred the costs related to such legal proceedings.

Benefit plans

Benefit plans	9 Months Ended
	Sep. 30, 2021
Benefit plans
Benefit plans	17. Benefit plans The Company established a defined contribution savings plan under Section 401(k) of the Code. This plan covers all employees who meet minimum age and service requirements and allows participants to defer a portion of their annual compensation on a pre-tax basis. Matching contributions to the plan may be made at the discretion of the Company’s board of directors. The Company made contributions of $0.1 million and less than $0.1 million to the plan during the three months ended September 30, 2021 and 2020, respectively, and $0.2 million and $0.1 million to the plan during the nine months ended September 30, 2021 and 2020, respectively.

Summary of significant accoun_2

Summary of significant accounting policies (Policies)	9 Months Ended
	Sep. 30, 2021
Summary of significant accounting policies
Use of estimates	Use of estimates The preparation of the Company’s condensed consolidated financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and the reported amounts of revenue and expenses during the reporting periods. Significant estimates and assumptions reflected in these condensed consolidated financial statements include, but are not limited to, calculating the standalone selling price for revenue recognition, the valuation of inventory, the valuation of common stock and stock-based awards, and the valuation of the preferred stock warrant liability. The Company bases its estimates on historical experience, known trends and other market-specific and relevant factors that it believes to be reasonable under the circumstances. On an ongoing basis, management evaluates its estimates when there are changes in circumstances, facts and experience. Changes in estimates are recorded in the period in which they become known. Actual results could differ from those estimates. Due to the COVID-19 pandemic, there has been uncertainty and disruption in the global economy and financial markets. The Company is not aware of any specific event or circumstance that would require an update to its estimates or judgments or a revision of the carrying value of its assets or liabilities. These estimates may change as new events occur and additional information is obtained. Other than policies noted below, there have been no significant changes to the significant accounting policies disclosed in Note 2 of the audited consolidated financial statements as of December 31, 2020 and 2019 and for the years ended December 31, 2020 and 2019, included in the Prospectus.
Risk of concentrations of credit, significant customers and significant suppliers	Risk of concentrations of credit, significant customers and significant suppliers Financial instruments that potentially expose the Company to concentrations of credit risk consist primarily of cash and cash equivalents, short-term investments and accounts receivable. Periodically, the Company maintains deposits in accredited financial institutions in excess of federally insured limits. The Company maintains its cash and cash equivalents with financial institutions that management believes to be of high credit quality. The Company has not experienced any losses on such accounts and does not believe it is exposed to any unusual credit risk beyond the normal credit risk associated with commercial banking relationships. The Company has not experienced any other-than-temporary losses with respect to its cash equivalents and investments and does not believe that it is subject to unusual credit risk beyond the normal credit risk associated with commercial banking relationships. Significant customers are those which represent more than 10% of the Company’s total revenue or accounts receivable balance at each respective balance sheet date. The following table presents customers that represent 10% or more of the Company’s total revenue: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, ​ Nine Months Ended September 30, ​ 2021 2020 2021 2020 Customer A 32.1 % 40.8 % 16.4 % 21.2 % Customer B * ​ * ​ * ​ 17.1 % Customer C * ​ * ​ * ​ 10.1 % Customer D ​ 11.4 % * ​ ​ * ​ * ​ Customer E ​ * ​ 18.8 % ​ * ​ * ​ ​ 43.5 % 59.6 % 16.4 % 48.4 % * – less than 10% The following table presents customers that represent 10% or more of the Company’s accounts receivable: ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, 2020 ​ 2021 2020 Customer A ​ 21.7 % 41.9 % Customer D ​ 20.2 % * ​ Customer E 11.1 % * ​ Customer F * ​ 10.1 % Customer G * ​ 13.4 % Customer H * ​ 18.7 % ​ 53.0 % 84.1 % * – less than 10%
Deferred offering costs	Deferred offering costs The Company capitalizes certain legal, accounting and other third-party fees that are directly associated with in-process equity financings as deferred offering costs until such financings are consummated. After consummation of an equity financing, these costs are recorded in stockholders’ equity (deficit) as a reduction of additional paid-in capital generated as a result of the offering or as a reduction to the carrying value of redeemable convertible preferred stock. If the in-process equity financing is abandoned, the deferred offering costs will be expensed immediately as a charge to operating expenses in the condensed consolidated statements of operations. As of September 30, 2021 and December 31, 2020, the Company had zero and $0.1 million, respectively, in deferred offering costs in the condensed consolidated balance sheets.
Debt issuance costs	Debt issuance costs The Company capitalizes certain legal and other third-party fees that are directly associated with the issuance of debt as debt issuance costs. Debt issuance costs are recorded as a direct reduction of the carrying amount of the associated debt on the condensed consolidated balance sheets and amortized as interest expense on the condensed consolidated statements of operations using the effective interest method, which approximates the straight-line method. As of September 30, 2021 and December 31, 2020, debt issuance costs totaled zero and $1.3 million, respectively. During the three months ended September 30, 2021 and 2020, the Company recorded $0.1 million in the respective periods, and during the nine months ended September 30, 2021 and 2020, the Company recorded $0.4 million and $0.7 million, respectively, of interest expense related to amortization of debt issuance costs in the condensed consolidated statement of operations.
Cash equivalents	Cash equivalents The Company considers all highly liquid investments with an original maturity of 90 days or less at the time of purchase to be cash equivalents. Cash equivalents that are readily convertible to cash are stated at cost, which approximates fair value. At September 30, 2021 and December 31, 2020, the Company held cash of $0.4 million and $0.1 million, respectively, in banks located outside of the United States.
Restricted cash	Restricted cash As of September 30, 2021 and December 31, 2020, the Company was required to maintain guaranteed investment certificates of $0.3 million and $0.1 million, respectively, with maturities of three months to one year that are subject to an insignificant risk of changes in value. The guaranteed investment certificates are held for the benefit of the landlord in connection with an operating lease which has a remaining term of greater than one year and are classified as restricted cash (non-current) on the Company’s consolidated balance sheets.
Software Development Costs	Software Development Costs The Company accounts for software development costs for internal-use software under the provisions of ASC 350-40, “Internal-Use Software
Fair value measurements	Fair value measurements Certain assets and liabilities of the Company are carried at fair value under GAAP. Fair value is defined as the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value must maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three levels of the fair value hierarchy, of which the first two are considered observable and the last is considered unobservable: ● Level 1—Quoted prices in active markets for identical assets or liabilities. ● Level 2—Observable inputs (other than Level 1 quoted prices), such as quoted prices in active markets for similar assets or liabilities, quoted prices in markets that are not active for identical or similar assets or liabilities, or other inputs that are observable or can be corroborated by observable market data. ● Level 3—Unobservable inputs that are supported by little or no market activity that are significant to determining the fair value of the assets or liabilities, including pricing models, discounted cash flow methodologies and similar techniques. The Company’s cash equivalents, short-term investments and its redeemable convertible preferred stock warrant liability are carried at fair value, determined according to the fair value hierarchy described above (see Note 3). The carrying values of the Company’s accounts receivable, prepaid expenses and other current assets, accounts payable and accrued expenses and other current liabilities approximate their fair values due to the short-term nature of these assets and liabilities. The carrying value of the Company’s long-term debt approximates its fair value (a level 2 measurement) at each balance sheet date due to its variable interest rate, which approximates a market interest rate.
Product warranties	Product warranties The Company offers a one-year limited assurance warranty on System sales, which is included in the selling price. The warranty accrual is included in accrued expenses and other current liabilities in the condensed consolidated balance sheets. The following table presents a summary of changes in the amount reserved for warranty cost (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Balance, beginning of the period ​ $ 612 ​ $ 757 ​ $ 637 ​ $ 848 Warranty repairs ​ — ​ (3) ​ (25) ​ (94) Balance, end of the year ​ $ 612 ​ $ 754 ​ $ 612 ​ $ 754 ​
Segment information	Segment information The Company determined its operating segment after considering the Company’s organizational structure and the information regularly reviewed and evaluated by the Company’s chief operating decision maker (“CODM”) in deciding how to allocate resources and assess performance. The Company has determined that its CODM is its Chief Executive Officer. The CODM reviews the financial information on a consolidated basis for purposes of evaluating financial performance and allocating resources. On the basis of these factors, the Company determined that it operates and manages its business as one operating segment, that develops, manufactures, markets and sells Systems and related LIMS connection software, consumables and services; and accordingly has one reportable segment for financial reporting purposes. Substantially all of the Company’s long-lived assets are held in the United States.
Revenue recognition	Revenue recognition Remaining performance obligations The Company does not disclose the value of remaining performance obligations for (i) contracts with an original contract term of one year or less, (ii) contracts for which the Company recognizes revenue at the amount to which it has the right to invoice when that amount corresponds directly with the value of services performed, and (iii) Contract balances from contracts with customers Contract assets arise from unbilled amounts in customer arrangements when revenue recognized exceeds the amount billed to the customer and the Company’s right to payment is conditional and not only subject to the passage of time. The Company had $1.1 million and $0.5 million in contract assets as of September 30, 2021 and December 31, 2020, respectively, included in prepaid expenses and other current assets. These balances relate to the BARDA (as defined below) agreements, as well as unbilled amounts with commercial customers. Contract liabilities represent the Company’s obligation to transfer goods or services to a customer for which it has received consideration (or the amount is due) from the customer. The Company has a contract liability related to service revenue, which consists of amounts that have been invoiced but that have not been recognized as revenue. Amounts expected to be recognized as revenue within 12 months of the balance sheet date are classified as current deferred revenue and amounts expected to be recognized as revenue beyond 12 months of the balance sheet date are classified as noncurrent deferred revenue. The Company did not record any non-current deferred revenue as of September 30, 2021 or December 31, 2020. Deferred revenue was $3.9 million and $4.4 million at September 30, 2021 and December 31, 2020. Revenue recognized during the three months ended September 30, 2021 and 2020 that was included in deferred revenue at the prior period-end was $0.7 million and $0.2 million, respectively. Revenue recognized during the nine months ended September 30, 2021 and 2020 that was included in deferred revenue at the prior period-end was $3.6 million and $0.8 million, respectively. Non-commercial revenue The Company generates revenue from a long-term contract with the U.S. Department of Health and Human Services Biomedical Advanced Research and Development Authority (“BARDA”) a part of the U.S. government. The Company’s contracts with the U.S. government typically are subject to the Federal Acquisition Regulation (“FAR”) and are priced based on estimated or actual costs of producing goods or providing services. The FAR provides guidance on the types of costs that are allowable in establishing prices for goods or services provided under U.S. government contracts. In September 2017, the Company signed a contract with BARDA, which was subsequently modified on multiple occasions to increase the contract value and adjust the cost share reimbursement rate. Modifications were accounted for in accordance with the contract modification framework. The contract is a cost-reimbursable, cost- sharing arrangement, whereby BARDA reimburses the Company for a percentage of the total costs that have been incurred including indirect allowable costs. Revenue on the BARDA contract is recognized over time using an input method based on cost incurred to date in relation to total estimated cost. Due to the structure of the arrangement, the transaction price is variable in nature based on actual cost incurred. As such the amount included in the transaction price is constrained to the amount for which it is probable that a significant reversal of cumulative revenue recognized will not occur. Disaggregated revenue The Company disaggregates revenue based on the recurring and non-recurring, and commercial and non-commercial, nature of the underlying sale. Recurring revenue includes sales of consumables and service contracts. Non-recurring revenue includes sales of Systems, LIMS connection software, validation services, field service, and revenue under the Company’s contract with BARDA. The following table presents the Company’s revenue by the recurring or non-recurring and commercial or non-commercial nature of the revenue stream (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Product and service revenue — recurring ​ $ 2,171 ​ $ 855 ​ $ 5,539 ​ $ 2,712 Product and service revenue — non-recurring ​ 4,132 ​ 4,109 ​ 11,243 ​ 6,269 Non-commercial revenue — non-recurring ​ 596 ​ 283 ​ 1,242 ​ 1,858 Total revenue ​ $ 6,899 ​ $ 5,247 ​ $ 18,024 ​ $ 10,839 The following table presents the Company’s revenue by customer geography (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 United States ​ $ 4,313 ​ $ 2,067 ​ $ 10,086 ​ $ 4,401 Germany ​ 298 ​ 312 ​ 1,263 ​ 1,547 Switzerland ​ 899 ​ 2,765 ​ 2,989 ​ 3,574 All other countries ​ 1,389 ​ ​ 103 ​ ​ 3,686 ​ ​ 1,317 Total revenue ​ $ 6,899 ​ $ 5,247 ​ $ 18,024 ​ $ 10,839 ​ Advertising costs Advertising costs are expensed as incurred and are included in sales and marketing expenses in the condensed consolidated statements of operations. Advertising costs were less than $0.1 million during the three and nine months ended September 30, 2021 and 2020.
Advertising costs	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 United States ​ $ 4,313 ​ $ 2,067 ​ $ 10,086 ​ $ 4,401 Germany ​ 298 ​ 312 ​ 1,263 ​ 1,547 Switzerland ​ 899 ​ 2,765 ​ 2,989 ​ 3,574 All other countries ​ 1,389 ​ ​ 103 ​ ​ 3,686 ​ ​ 1,317 Total revenue ​ $ 6,899 ​ $ 5,247 ​ $ 18,024 ​ $ 10,839
Stock-based compensation	Stock-based compensation The Company measures all stock-based awards granted to employees, officers and directors based on their fair value on the date of the grant and recognizes compensation expense for those awards over the requisite service period, which is generally the vesting period of the respective award. The Company issues stock-based awards with only service-based vesting conditions and records the expense for these awards using the straight-line method. Forfeitures are accounted for prospectively as they occur. The Company measures all restricted common stock granted to employees based on the common stock value on the date of grant. The purchase price of the restricted common stock is the common stock value on the date of grant. The restricted common stock includes a repurchase right, whereas upon the occurrence of a specific event, the Company shall have the right to repurchase unvested restricted common stock shares. At September 30, 2021 and December 31, 2020, the Company has $0.7 million and zero, respectively, in unvested restricted Class A common stock liability included in other long-term liabilities.
Comprehensive loss	Comprehensive loss Comprehensive loss includes net loss as well as other changes in stockholders’ deficit that result from transactions and economic events other than those with stockholders. For the three months ended September 30, 2021 and 2020, there were no other adjustments to comprehensive income or loss, and for the nine months ended September 30, 2021 and 2020, comprehensive loss included less than $0.1 million and zero, respectively, of unrealized gains on short-term investments, net of tax.
Recently adopted and issued accounting pronouncements	Recently adopted accounting pronouncements I 2018, the FASB issued ASU No. 2018-15, Intangibles — Goodwill and Other — Internal-Use Software (Topic 35): Customer’s Accounting for Implementation Costs Incurred in a Cloud Computing Arrangement that is a Service Contract, which requires capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The Company adopted this guidance effective on January 1, 2021 and adoption did not have a material impact on the condensed consolidated financial statements and related disclosures. Recently issued accounting pronouncements The Company qualifies as an “emerging growth company” as defined in the Jumpstart Our Business Startups Act of 2012 and has elected not to “opt out” of the extended transition related to complying with new or revised accounting standards, which means that when a standard is issued or revised and it has different application dates for public and nonpublic companies, the Company will adopt the newer revised standard at the time nonpublic companies adopt the new or revised standard and will do so until such time that the Company either (i) irrevocably elects to “opt out” of such extended transition period or (ii) no longer qualifies as an emerging growth company. The Company may choose to early adopt any new or revised accounting standards whenever such early adoption is permitted for nonpublic companies. In June 2016, the FASB issued ASU No. 2016-13, Financial Instruments — Credit Losses (Topic 326) In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) (“ASU 2016-02”), which sets out the principles for the recognition, measurement, presentation and disclosure of leases for both parties to a contract (i.e., lessees and lessors). The new standard requires lessees to apply a dual approach, classifying leases as either finance or operating leases based on the principle of whether or not the lease is effectively a financed purchase by the lessee. This classification will determine whether lease expense is recognized based on an effective interest method or on a straight-line basis over the term of the lease. A lessee is also required to record a right-of-use asset and a lease liability for all leases with a term of greater than 12 months regardless of their classification. Leases with a term of 12 months or less may be accounted for similar to existing guidance for operating leases today. For public business entities, ASU 2016-02 is effective for annual reporting periods beginning after December 15, 2018, including interim periods within those fiscal years, and early adoption is permitted. For nonpublic entities, this guidance is effective for annual periods beginning after December 15, 2021. The Company expects to adopt this guidance effective January 1, 2022, and it is currently evaluating the impact on its condensed consolidated financial statements and related disclosures. In December 2019, the FASB issued ASU 2019-12, Income Taxes (ASC 740): Simplifying the Accounting for Income Taxes

Summary of significant accoun_3

Summary of significant accounting policies (Tables)	9 Months Ended
	Sep. 30, 2021
Summary of significant accounting policies
Schedule of concentration risk of customers that represent 10% or more of the Company's total revenue and accounts receivable	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, ​ Nine Months Ended September 30, ​ 2021 2020 2021 2020 Customer A 32.1 % 40.8 % 16.4 % 21.2 % Customer B * ​ * ​ * ​ 17.1 % Customer C * ​ * ​ * ​ 10.1 % Customer D ​ 11.4 % * ​ ​ * ​ * ​ Customer E ​ * ​ 18.8 % ​ * ​ * ​ ​ 43.5 % 59.6 % 16.4 % 48.4 % * – less than 10% The following table presents customers that represent 10% or more of the Company’s accounts receivable: ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, 2020 ​ 2021 2020 Customer A ​ 21.7 % 41.9 % Customer D ​ 20.2 % * ​ Customer E 11.1 % * ​ Customer F * ​ 10.1 % Customer G * ​ 13.4 % Customer H * ​ 18.7 % ​ 53.0 % 84.1 % * – less than 10%
Summary of changes in the amount reserved for warranty cost	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Balance, beginning of the period ​ $ 612 ​ $ 757 ​ $ 637 ​ $ 848 Warranty repairs ​ — ​ (3) ​ (25) ​ (94) Balance, end of the year ​ $ 612 ​ $ 754 ​ $ 612 ​ $ 754
Schedule of disaggregated revenue by nature and geographic location	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Product and service revenue — recurring ​ $ 2,171 ​ $ 855 ​ $ 5,539 ​ $ 2,712 Product and service revenue — non-recurring ​ 4,132 ​ 4,109 ​ 11,243 ​ 6,269 Non-commercial revenue — non-recurring ​ 596 ​ 283 ​ 1,242 ​ 1,858 Total revenue ​ $ 6,899 ​ $ 5,247 ​ $ 18,024 ​ $ 10,839 The following table presents the Company’s revenue by customer geography (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 United States ​ $ 4,313 ​ $ 2,067 ​ $ 10,086 ​ $ 4,401 Germany ​ 298 ​ 312 ​ 1,263 ​ 1,547 Switzerland ​ 899 ​ 2,765 ​ 2,989 ​ 3,574 All other countries ​ 1,389 ​ ​ 103 ​ ​ 3,686 ​ ​ 1,317 Total revenue ​ $ 6,899 ​ $ 5,247 ​ $ 18,024 ​ $ 10,839 ​

Fair value of financial asset_2

Fair value of financial assets and liabilities (Tables)	9 Months Ended
	Sep. 30, 2021
Fair value of financial assets and liabilities
Schedule of information about the Company's financial assets and liabilities measured at fair value on a recurring basis	The following tables present information about the Company’s financial assets and liabilities measured at fair value on a recurring basis and indicate the level of the fair value hierarchy used to determine such fair values (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value measurements as of September 30, 2021 ​ Level 1 Level 2 Level 3 Total Assets ​ ​ ​ ​ ​ Cash equivalents ​ $ 212,833 ​ $ — ​ $ — ​ $ 212,833 ​ ​ $ 212,833 ​ $ — ​ $ — ​ $ 212,833 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair value measurements at December 31, 2020 ​ Level 1 Level 2 Level 3 Total Assets ​ ​ ​ ​ ​ Cash equivalents ​ $ 23,456 ​ $ — ​ $ — ​ $ 23,456 Short-term investments ​ 14,998 ​ — ​ — ​ 14,998 ​ ​ $ 38,454 ​ $ — ​ $ — ​ $ 38,454 Liabilities ​ ​ ​ ​ ​ Preferred stock warrant liability ​ $ — ​ $ — ​ $ 4,117 ​ $ 4,117 ​ ​ $ — ​ $ — ​ $ 4,117 ​ $ 4,117
Schedule of information about weighted average of the unobservable inputs used to fair value the preferred stock warrant liability	The table below quantifies the weighted average of the unobservable inputs used to fair value the preferred stock warrant liability prior to their conversion into common stock warrants: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Fair value of Series A1 preferred stock ​ $ 4.00 ​ $ 0.39 ​ ​ $ 3.01 ​ $ 0.45 ​ Fair value of Series B1 preferred stock ​ $ 4.00 ​ $ 1.17 ​ ​ $ 3.26 ​ $ 1.13 ​ Fair value of Series C1 preferred stock ​ $ 4.00 ​ $ 1.15 ​ ​ $ 3.30 ​ $ 1.15 ​ Remaining contractual term (in years) ​ 6.6 ​ 7.4 ​ ​ 6.8 ​ 7.7 ​ Risk-free interest rate ​ 1.0 % 0.6 % ​ 1.2 % 0.6 % Expected dividend yield ​ — % — % ​ — % — % Expected volatility ​ 42.2 % 40.3 % ​ 42.0 % 39.3 %
Schedule of information provides a rollforward of the aggregate fair values of the Company's preferred stock warrant liability	The following table provides a rollforward of the aggregate fair values of the Company’s preferred stock warrant liability, for which fair values are determined using Level 3 inputs (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Balance, beginning of period ​ $ 15,600 ​ $ 3,499 ​ $ 4,117 ​ $ 3,396 Initial fair value of Series C1 preferred stock warrants ​ ​ — ​ ​ — ​ ​ — ​ ​ 652 Change in fair value of preferred stock warrants ​ 8,160 ​ — ​ 19,643 ​ (549) Conversion of preferred stock warrants to common stock warrants ​ (23,760) ​ — ​ (23,760) ​ — Balance, end of period ​ $ — ​ $ 3,499 ​ $ — ​ $ 3,499

Short-term investments (Tables)

Short-term investments (Tables)	9 Months Ended
	Sep. 30, 2021
Short-term investments
Schedule of short-term investments by investment type	Short-term investments by investment type consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ ​ Gross ​ Gross ​ ​ ​ ​ Amortized unrealized unrealized Fair ​ cost gains losses value U.S. Treasury bonds ​ $ 14,997 ​ $ 1 ​ $ — ​ $ 14,998 ​ ​ $ 14,997 ​ $ 1 ​ $ — ​ $ 14,998

Inventory (Tables)

Inventory (Tables)	9 Months Ended
	Sep. 30, 2021
Inventory
Summary of Inventory	Inventory consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2021 2020 Raw materials ​ $ 10,315 ​ $ 6,754 Work in process ​ 689 ​ 1,190 Finished goods ​ 3,163 ​ 1,021 Total ​ $ 14,167 ​ $ 8,965

Prepaid expenses and other cu_2

Prepaid expenses and other current assets (Tables)	9 Months Ended
	Sep. 30, 2021
Prepaid expenses and other current assets
Schedule of prepaid expenses and other current assets	Prepaid expenses and other current assets consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2021 2020 Prepaid insurance ​ $ 2,621 ​ $ 355 Prepaid commitment fee on notes payable ​ ​ — ​ ​ 275 Contract asset ​ 1,065 ​ 471 Deposits ​ 1,415 ​ 1,148 Lease receivables, current portion ​ 282 ​ 325 Other ​ 17 ​ 546 ​ ​ $ 5,400 ​ $ 3,120

Property and equipment, net (Ta

Property and equipment, net (Tables)	9 Months Ended
	Sep. 30, 2021
Property and equipment, net
Schedule of property and equipment, net	Property and equipment, net consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2021 2020 Manufacturing and laboratory equipment ​ $ 13,198 ​ $ 12,961 Computer hardware and software ​ 1,637 ​ 1,088 Office furniture and fixtures ​ 723 ​ 343 Leasehold improvements ​ ​ 3,012 ​ ​ 2,996 Construction-in-process ​ 1,454 ​ — ​ ​ 20,024 ​ 17,388 Less: Accumulated depreciation ​ (11,391) ​ (10,336) ​ ​ $ 8,633 ​ $ 7,052

Accrued expenses and other cu_2

Accrued expenses and other current liabilities (Tables)	9 Months Ended
	Sep. 30, 2021
Accrued expenses and other current liabilities
Schedule of accrued expenses and other current liabilities	Accrued expenses and other current liabilities consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2021 2020 Accrued employee compensation and benefits expense ​ $ 3,500 ​ $ 3,083 Accrued vendor expenses ​ 5,885 ​ 1,685 Accrued warranty expense ​ 612 ​ 637 Accrued interest ​ — ​ 330 Deferred rent, current portion ​ 127 ​ 118 Accrued taxes ​ 748 ​ 688 Other ​ 694 ​ 113 ​ ​ $ 11,566 ​ $ 6,654

Long-term debt (Tables)

Long-term debt (Tables)	9 Months Ended
	Sep. 30, 2021
Long-term debt
Schedule of components of the Company's long-term debt	The components of the Company’s long-term debt consisted of the following (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, ​ December 31, ​ 2021 2020 Notes payable ​ $ — ​ $ 25,000 Payment in kind interest ​ — ​ 1,145 Less: Unamortized discount ​ — ​ (1,335) Long-term debt, net of discount ​ $ — ​ $ 24,810

Redeemable convertible prefer_2

Redeemable convertible preferred stock (Tables)	9 Months Ended
	Sep. 30, 2021
Redeemable convertible preferred stock.
Schedule of preferred stock	As of December 31, 2020, Preferred Stock consisted of the following (in thousands, except for share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ Preferred stock ​ ​ ​ ​ ​ ​ Common stock ​ Preferred stock issued and ​ Liquidation issuable upon ​ authorized outstanding Carrying value preference conversion Series A1 Preferred Stock ​ 22,563,639 ​ 18,740,115 ​ $ 18,542 ​ $ 21,176 ​ 3,748,022 Series B1 Preferred Stock ​ 61,217,425 ​ 60,017,425 ​ ​ 68,511 ​ ​ 90,026 ​ 12,003,474 Series C1 Preferred Stock ​ 57,372,796 ​ 33,962,271 ​ ​ 40,632 ​ ​ 58,585 ​ 6,792,445 Series C2 Preferred Stock 20,301,829 20,301,829 ​ 24,141 ​ 35,021 4,060,365 ​ 161,455,689 133,021,640 ​ $ 151,826 ​ $ 204,808 26,604,306

Preferred stock warrants (Table

Preferred stock warrants (Tables)	9 Months Ended
	Sep. 30, 2021
Preferred stock warrant
Preferred stock warrants
Schedule of warrants to purchase the following classes of preferred stock outstanding	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ Series of ​ ​ ​ Preferred ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ redeemable ​ ​ ​ shares ​ Weighted ​ ​ ​ ​ ​ Contractual ​ convertible ​ ​ ​ issuable upon ​ average ​ ​ ​ ​ ​ term ​ preferred ​ Balance sheet ​ exercise ​ exercise ​ Warrant fair Issuance date (in years) stock classification of warrant price value April 24, 2017 10 Series A1 Liability 3,823,524 ​ $ 0.01 ​ $ 1,875 April 12, 2018 10 Series B1 Liability 1,199,994 ​ $ 0.01 ​ 1,501 May 14, 2020 10 Series C1 Liability 1,195,652 ​ $ 1.15 ​ 741 ​ ​ ​ ​ ​ ​ ​ 6,219,170 ​ ​ ​ ​ $ 4,117

Common stock and common stock_2

Common stock and common stock warrants (Tables)	9 Months Ended
	Sep. 30, 2021
Common stock and common stock warrant
Preferred stock warrants
Schedule of warrants to purchase the following classes of preferred stock outstanding	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ September 30, 2021 ​ ​ ​ ​ Shares of ​ ​ ​ ​ ​ ​ ​ ​ common stock ​ ​ ​ ​ ​ ​ ​ Balance sheet ​ issuable upon ​ Weighted average Issuance date Contractual term classification exercise of warrant exercise price ​ ​ (in years) ​ ​ ​ ​ ​ ​ ​ July 24, 2017 ​ 10 ​ Equity ​ 25,835 ​ $ 295.15 April 12, 2018 ​ 10 ​ Equity ​ 30,000 ​ $ 1.00 July 14, 2021 ​ 10 ​ Equity ​ 975,109 ​ $ 1.46 ​ ​ ​ ​ ​ ​ 1,030,944 ​ ​ ​ ​ As of December 31, 2020, outstanding warrants to purchase common stock outstanding consisted of the following: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 31, 2020 ​ ​ ​ ​ Shares of ​ ​ ​ ​ ​ ​ ​ ​ common stock ​ ​ ​ ​ ​ ​ ​ Balance sheet ​ issuable upon ​ Weighted average Issuance date Contractual term classification exercise of warrant exercise price ​ ​ (in years) ​ ​ ​ ​ ​ ​ ​ July 24, 2017 ​ 10 ​ Equity ​ 25,835 ​ $ 295.15 April 12, 2018 ​ 10 ​ Equity ​ 30,000 ​ $ 1.00 ​ ​ ​ ​ ​ ​ 55,835 ​ ​ ​

Stock-based compensation (Table

Stock-based compensation (Tables)	9 Months Ended
	Sep. 30, 2021
Stock-based compensation
Schedule of assumptions used to determine the grant-date fair value of stock options	The following table presents, on a weighted average basis, the assumptions used in the Black-Scholes option-pricing model to determine the grant-date fair value of stock options granted to employees and directors: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, ​ Nine Months Ended September 30, ​ 2021 2020 2021 2020 Risk-free interest rate 0.96 % 0.34 % 0.90 % 0.36 % Expected term (in years) 5.8 6.0 ​ 6.0 6.0 ​ Expected volatility 43.7 % 90.4 % 51.5 % 90.3 % Expected dividend yield 0 % 0 % 0 % 0 %
Schedule of stock option activity	The following table summarizes the Company’s stock option activity since December 31, 2020 (in thousands, except for share and per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ ​ ​ ​ ​ Weighted ​ average ​ ​ ​ ​ Number of ​ average ​ remaining ​ Aggregate ​ shares exercise price contractual term intrinsic value ​ ​ ​ ​ ​ ​ ​ (in years) ​ ​ ​ Outstanding as of December 31, 2020 3,604,584 ​ $ 0.92 8.12 ​ $ 4,272 Granted 1,732,182 ​ 9.15 ​ ​ ​ ​ ​ Exercised (111,149) ​ 2.67 ​ Expired (34,447) ​ 1.00 ​ Forfeited (667,866) ​ 2.12 ​ Outstanding as of September 30, 2021 4,523,304 ​ $ 3.88 7.68 ​ $ 66,231 Options vested and expected to vest as of September 30, 2021 4,523,304 ​ $ 3.88 7.68 ​ $ 66,231 Options exercisable as of September 30, 2021 2,134,381 ​ $ 1.25 6.17 ​ $ 36,777
Schedule of restricted stock activity	The following table summarizes the Company’s restricted stock activity since December 31, 2020 (in thousands except for share and per share data): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted ​ ​ Number of ​ average ​ shares fair value ​ ​ ​ ​ (in years) Unvested as of December 31, 2020 ​ - ​ ​ ​ Granted ​ 248,903 ​ $ 2.10 Vested ​ - ​ ​ ​ Forfeited ​ - ​ ​ ​ Unvested as of September 30, 2021 ​ 248,903 ​ $ 2.10
Schedule of stock-based compensation expense was classified in the consolidated statements of operations	Stock-based compensation expense was classified in the condensed consolidated statements of operations as follows (in thousands): ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Cost of revenue ​ $ 106 ​ $ 20 ​ $ 221 ​ $ 62 General and administrative ​ 345 ​ 72 ​ 680 ​ 223 Sales and marketing ​ 76 ​ 11 ​ 158 ​ 42 Research and development ​ 57 ​ 12 ​ 106 ​ 34 Total stock-based compensation expense ​ $ 584 ​ $ 115 ​ $ 1,165 ​ $ 361

Net loss per share (Tables)

Net loss per share (Tables)	9 Months Ended
	Sep. 30, 2021
Net loss per share
Schedule of basic and diluted net loss per share	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended September 30, Nine Months Ended September 30, ​ 2021 2020 2021 2020 Numerator: ​ ​ ​ ​ ​ ​ ​ ​ Net loss ​ $ (24,987) ​ $ (8,465) ​ $ (58,919) ​ $ (25,739) Accretion of redeemable convertible preferred stock to redemption value ​ 210 ​ (832) ​ (1,761) ​ (2,882) Cumulative redeemable convertible preferred stock dividends ​ (451) ​ (1,412) ​ (2,747) ​ (2,987) Net loss attributable to common stockholders—basic and diluted ​ $ (25,228) ​ $ (10,709) ​ $ (63,427) ​ $ (31,608) Denominator: ​ ​ ​ ​ Weighted average Class A common shares outstanding—basic and diluted ​ ​ 29,463,234 ​ ​ 356,074 ​ ​ 10,372,225 ​ ​ 354,341 Weighted average Class B common shares outstanding—basic and diluted ​ ​ 5,852,865 ​ ​ — ​ ​ 1,972,394 ​ ​ — Total shares for EPS—basic and diluted ​ ​ 35,316,099 ​ ​ 356,074 ​ ​ 12,344,619 ​ ​ 354,341 Net loss per share attributable to Class A common stockholders—basic and diluted ​ ​ (0.71) ​ ​ (30.08) ​ ​ (5.14) ​ ​ (89.20) Net loss per share attributable to Class B common stockholders—basic and diluted ​ (0.71) ​ — ​ (5.14) ​ —
Schedule of common shares excluded from the computation of diluted net loss per share	​ ​ ​ ​ ​ ​ ​ September 30, ​ 2021 2020 Options to purchase common stock 4,772,207 4,005,581 Warrants to purchase common stock 294,965 55,872 Redeemable convertible preferred stock (as converted to common stock) — 26,604,306 Warrants to purchase preferred stock (as converted to warrants to purchase common stock) — 1,243,834 ​ 5,067,172 31,909,593

Commitments and contingencies (

Commitments and contingencies (Tables)	9 Months Ended
	Sep. 30, 2021
Commitments and contingencies
Schedule of future minimum lease commitments under operating leases	Future minimum lease commitments under operating leases as of September 30, 2021 are as follows (in thousands): ​ ​ ​ ​ Year ending December 31, ​ 2021 ​ $ 169 2022 ​ 1,139 2023 ​ 1,169 2024 ​ 1,199 2025 ​ 1,229 Thereafter ​ 2,997 Total ​ $ 7,902

Nature of the business and ba_2

Nature of the business and basis of presentation - Initial Public Offering (Details) $ / shares in Units, $ in Thousands	Aug. 04, 2021USD ($)$ / sharesshares	Jul. 19, 2021USD ($)$ / sharesshares	Jul. 09, 2021	Sep. 30, 2021USD ($)
Class of Stock [Line Items]
Gross proceeds				$ 165,453
Reverse stock split ratio			0.2
IPO
Class of Stock [Line Items]
Stock issued during period shares new issues | shares		7,920,000
Share issued, price per share | $ / shares		$ 20
Gross proceeds		$ 158,400
Net proceeds		$ 143,800
Over Allotment Option
Class of Stock [Line Items]
Stock issued during period shares new issues | shares	1,086,604
Share issued, price per share | $ / shares	$ 20
Net proceeds	$ 20,200

Nature of the business and ba_3

Nature of the business and basis of presentation - Going Concern (Details) - USD ($) $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Nature of the business and basis of presentation
Net loss	$ (24,987)	$ (11,831)	$ (22,101)	$ (8,465)	$ (9,267)	$ (8,007)	$ (58,919)	$ (25,739)
Accumulated deficit	$ (300,507)						$ (300,507)		$ (241,588)

Summary of significant accoun_4

Summary of significant accounting policies - Risk of Concentrations of Credit, Significant Customers and Significant Suppliers (Details) - Customers	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Total revenue | Major Customers
Concentration Risk [Line Items]
Customer concentration risk percentage	43.50%	59.60%	16.40%	48.40%
Total revenue | Customer A
Concentration Risk [Line Items]
Customer concentration risk percentage	32.10%	40.80%	16.40%	21.20%
Total revenue | Customer B
Concentration Risk [Line Items]
Customer concentration risk percentage				17.10%
Total revenue | Customer C
Concentration Risk [Line Items]
Customer concentration risk percentage				10.10%
Total revenue | Customer D
Concentration Risk [Line Items]
Customer concentration risk percentage	11.40%
Total revenue | Customer E
Concentration Risk [Line Items]
Customer concentration risk percentage		18.80%
Accounts receivable | Major Customers
Concentration Risk [Line Items]
Customer concentration risk percentage			53.00%		84.10%
Accounts receivable | Customer A
Concentration Risk [Line Items]
Customer concentration risk percentage			21.70%		41.90%
Accounts receivable | Customer D
Concentration Risk [Line Items]
Customer concentration risk percentage			20.20%
Accounts receivable | Customer E
Concentration Risk [Line Items]
Customer concentration risk percentage			11.10%
Accounts receivable | Customer F
Concentration Risk [Line Items]
Customer concentration risk percentage					10.10%
Accounts receivable | Customer G
Concentration Risk [Line Items]
Customer concentration risk percentage					13.40%
Accounts receivable | Customer H
Concentration Risk [Line Items]
Customer concentration risk percentage					18.70%

Summary of significant accoun_5

Summary of significant accounting policies - Deferred Offering Costs (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Summary of significant accounting policies
Deferred offering costs	$ 0	$ 100,000

Summary of significant accoun_6

Summary of significant accounting policies - Debt Issuance Costs (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Summary of significant accounting policies
Debt issuance costs	$ 0		$ 0		$ 1,300,000
Amortization of the debt issuance costs	$ 100,000	$ 100,000	$ 400,000	$ 700,000

Summary of significant accoun_7

Summary of significant accounting policies - Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Summary of significant accounting policies
Cash	$ 0.4	$ 0.1
Guaranteed investment certificates	0.3	$ 0.1
Software development costs capitalized	$ 1.1

Summary of significant accoun_8

Summary of significant accounting policies - Product Warranties (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Summary of significant accounting policies
Balance, beginning of the period	$ 612	$ 757	$ 637	$ 848
Warranty repairs	0	(3)	(25)	(94)
Balance, end of the year	$ 612	$ 754	$ 612	$ 754
Warranty duration			1 year

Summary of significant accoun_9

Summary of significant accounting policies - Segment Information (Details)	9 Months Ended
	Sep. 30, 2021segment
Summary of significant accounting policies
Number of operating segments	1
Number of reportable segments	1

Summary of significant accou_10

Summary of significant accounting policies - Revenue Recognition (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Deferred revenue	$ 3.9		$ 3.9		$ 4.4
Revenue recognized included in deferred revenue in prior period	0.7	$ 0.2	3.6	$ 0.8
Prepaid expenses and other current asset | Barda Agreement
Disaggregation of Revenue [Line Items]
Contract assets	$ 1.1		$ 1.1		$ 0.5

Summary of significant accou_11

Summary of significant accounting policies - Disaggregated Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Disaggregation of Revenue [Line Items]
Revenue recognized	$ 6,899	$ 5,247	$ 18,024	$ 10,839
United states
Disaggregation of Revenue [Line Items]
Revenue recognized	4,313	2,067	10,086	4,401
Germany
Disaggregation of Revenue [Line Items]
Revenue recognized	298	312	1,263	1,547
Switzerland
Disaggregation of Revenue [Line Items]
Revenue recognized	899	2,765	2,989	3,574
All other countries
Disaggregation of Revenue [Line Items]
Revenue recognized	1,389	103	3,686	1,317
Product and service revenue - recurring
Disaggregation of Revenue [Line Items]
Revenue recognized	2,171	855	5,539	2,712
Product and service revenue - non-recurring
Disaggregation of Revenue [Line Items]
Revenue recognized	4,132	4,109	11,243	6,269
Non-commercial revenue - non-recurring
Disaggregation of Revenue [Line Items]
Revenue recognized	$ 596	$ 283	$ 1,242	$ 1,858

Summary of significant accou_12

Summary of significant accounting policies - Advertising Costs (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Maximum
Class of Stock [Line Items]
Advertising costs	$ 0.1	$ 0.1	$ 0.1	$ 0.1

Summary of significant accou_13

Summary of significant accounting policies - Stock-based compensation (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Other long-term liabilities | Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Amount of restricted common stock liability	$ 0.7	$ 0

Summary of significant accou_14

Summary of significant accounting policies - Comprehensive Loss (Details) - USD ($)	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Unrealized loss on short-term investments, net of tax	$ (1,000)	$ 0
Maximum
Unrealized loss on short-term investments, net of tax	$ (100,000)

Fair value of financial asset_3

Fair value of financial assets and liabilities - Financial Assets and Liabilities Measured at Fair Value (Details) - Recurring - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Assets
Cash equivalents	$ 212,833	$ 23,456
Short-term investments		14,998
Assets	212,833	38,454
Liabilities
Preferred stock warrant liability		4,117
Liabilities		4,117
Level 1
Assets
Cash equivalents	212,833	23,456
Short-term investments		14,998
Assets	$ 212,833	38,454
Level 3
Liabilities
Preferred stock warrant liability		4,117
Liabilities		$ 4,117

Fair value of financial asset_4

Fair value of financial assets and liabilities - Transfers (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Fair value of financial assets and liabilities
Asset transferred, L1 to L2	$ 0	$ 0	$ 0	$ 0
Asset transferred, L2 to L1	0	0	0	0
Liabilities transferred, L1 to L2	0	0	0	0
Liabilities transferred, L2 to L1	0	0	0	0
Asset transferred, into L3	0	0	0	0
Asset transferred, out of L3	0	0	0	0
Liabilities transferred, into L3	0	0	0	0
Liabilities transferred, out of L3	$ 0	$ 0	0	$ 0
Fair value assessment charges			$ 8,200

Fair value of financial asset_5

Fair value of financial assets and liabilities - Weighted Average of the Unobservable Inputs Used to Fair Value (Details) - Level 3	3 Months Ended		9 Months Ended
	Sep. 30, 2021Y$ / shares	Sep. 30, 2020Y$ / shares	Sep. 30, 2021Y$ / shares	Sep. 30, 2020Y$ / shares
Remaining contractual term (in years)
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Preferred stock warrant liability, measurement input | Y	6.6	7.4	6.8	7.7
Risk-free interest rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Preferred stock warrant liability, measurement input	0.010	0.006	0.012	0.006
Expected volatility
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Preferred stock warrant liability, measurement input	0.422	0.403	0.420	0.393
Series A1 Redeemable Convertible Preferred Stock
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of preferred stock warrant liability	$ 4	$ 0.39	$ 3.01	$ 0.45
Series B1 Redeemable Convertible Preferred Stock
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of preferred stock warrant liability	4	1.17	3.26	1.13
Series C1 Redeemable Convertible Preferred Stock
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Fair value of preferred stock warrant liability	$ 4	$ 1.15	$ 3.30	$ 1.15

Fair value of financial asset_6

Fair value of financial assets and liabilities - Rollforward of the Aggregate Fair Values (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Conversion of preferred stock warrants to common stock warrants			$ 23,760
Preferred stock warrant liability
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balance, beginning of period	$ 15,600	$ 3,499	4,117	$ 3,396
Change in fair value	8,160		19,643	(549)
Conversion of preferred stock warrants to common stock warrants	(23,760)		(23,760)
Balance, end of period		3,499		3,499
Preferred stock warrant liability | Series C1 preferred Stock Warrants
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Initial fair value	$ 0	$ 0	$ 0	$ 652

Short-term investments (Details

Short-term investments (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020
Debt Securities, Available-for-sale [Line Items]
Amortized cost		$ 14,997,000
Gross unrealized gains		1,000
Fair value		14,998,000
Short-term investments	$ 0	14,998,000
U.S. Treasury bonds
Debt Securities, Available-for-sale [Line Items]
Amortized cost		14,997,000
Gross unrealized gains		1,000
Fair value		$ 14,998,000

Inventory (Details)

Inventory (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Inventory
Raw materials	$ 10,315	$ 6,754
Work in process	689	1,190
Finished goods	3,163	1,021
Total	$ 14,167	$ 8,965

Prepaid expenses and other cu_3

Prepaid expenses and other current assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Prepaid expenses and other current assets
Prepaid insurance	$ 2,621	$ 355
Prepaid commitment fee on notes payable		275
Contract asset	1,065	471
Deposits	1,415	1,148
Lease receivables, current portion	282	325
Other	17	546
Prepaid expenses and other current assets	$ 5,400	$ 3,120

Property and equipment, net (De

Property and equipment, net (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 20,024	$ 17,388
Less: Accumulated depreciation	(11,391)	(10,336)
Property plant and equipment, net	8,633	7,052
Manufacturing and laboratory equipment
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	13,198	12,961
Computer hardware and software
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	1,637	1,088
Office furniture and fixtures
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	723	343
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	3,012	$ 2,996
Construction-in-process
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	$ 1,454

Property and equipment, net - D

Property and equipment, net - Depreciation and amortization (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Depreciation and amortization expense	$ 400,000	$ 300,000	$ 1,079,000	$ 1,190,000
Fully depreciated assets disposed of	0	$ 0		$ 0
Property plant and equipment, gross	20,024,000		20,024,000		$ 17,388,000
Accumulated depreciation	11,391,000		11,391,000		10,336,000
Assets held under capital leases
Property, Plant and Equipment [Line Items]
Property plant and equipment, gross	400,000		400,000		0
Accumulated depreciation	100,000		100,000		$ 0
Capital lease future minimum payment due	600,000		600,000
Capital lease future minimum payment due, interest	$ 200,000		200,000
Maximum
Property, Plant and Equipment [Line Items]
Fully depreciated assets disposed of			$ 100,000

Accrued expenses and other cu_3

Accrued expenses and other current liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Accrued expenses and other current liabilities
Accrued employee compensation and benefits expense	$ 3,500	$ 3,083
Accrued vendor expenses	5,885	1,685
Accrued warranty expense	612	637
Accrued interest		330
Deferred rent, current portion	127	118
Accrued taxes	748	688
Other	694	113
Accrued expenses and other current liabilities	$ 11,566	$ 6,654

Long-term debt - Components of

Long-term debt - Components of Long-term Debt (Details) $ in Thousands	Dec. 31, 2020USD ($)
Debt Instrument [Line Items]
Less: Unamortized discount	$ (1,335)
Long-term debt, net of discount	24,810
Notes payable
Debt Instrument [Line Items]
Long-term debt	25,000
Payment in kind interest
Debt Instrument [Line Items]
Long-term debt	$ 1,145

Long-term debt - Term loans and

Long-term debt - Term loans and convertible notes (Details) $ / shares in Units, $ in Thousands	1 Months Ended			3 Months Ended		9 Months Ended
	May 31, 2020USD ($)item$ / sharesshares	Apr. 30, 2020USD ($)shares	Feb. 29, 2020USD ($)	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)	Apr. 30, 2018USD ($)
Debt Instrument [Line Items]
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs						$ 79,743	$ 49,935
Value of stock issued upon conversion of convertible preferred stock				$ 236,077
Loss on extinguishment of debt				3,100		3,100	2,910
Long-term Debt.								$ 24,810
Series C1 Redeemable Convertible Preferred Stock
Debt Instrument [Line Items]
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs		$ 27,200
2018 Term Loan
Debt Instrument [Line Items]
Loan amount									$ 18,000
Debt paid	$ 19,400
Non-refundable end of term charges paid	1,300
Accrued interest paid	600
Early termination fee paid	100
Write off of debt issuance cost and end of term exit fee							700
Early payment and documentation fees							100
Interest expenses					$ 100		800
Amortization of debt discount					100		200
Loss on extinguishment of debt							2,900
2020 Term Loan
Debt Instrument [Line Items]
Loan amount	60,000
Interest expenses				700		2,500
Amortization of debt discount	300			100		300
Facility fees	$ 800
Number of loan tranches | item	3
Debt issuance costs	$ 1,500
Professional fees	900
Debt issuance cost allocated to warrant issued	$ 600
Loss on extinguishment of debt						3,100
Prepayment Penalty						1,800
Expense to unamortized discounts						1,100
Unamortized prepaid facility fees and other charges						200
Long-term Debt.				$ 0		$ 0
2020 Term Loan | Series C1 Redeemable Convertible Preferred Stock
Debt Instrument [Line Items]
Shares issued upon conversion of warrant | shares	1,195,652
Exercise price | $ / shares	$ 1.15
2020 Term Loan- Tranche One
Debt Instrument [Line Items]
Loan amount	$ 25,000
2020 Term Loan- Tranche Two and Three
Debt Instrument [Line Items]
Loan amount	35,000
2020 Term Loan- Tranche Two
Debt Instrument [Line Items]
Loan amount	20,000
Debt issuance costs	300
2020 Term Loan- Tranche Three
Debt Instrument [Line Items]
Loan amount	15,000
Debt issuance costs	$ 200
Convertible Notes
Debt Instrument [Line Items]
Loan amount			$ 9,500
Interest rate			1.50%
Interest expenses					$ 0		$ 400
Debt			$ 7,100
Value of stock issued upon conversion of convertible preferred stock			$ 20,000
Percentage of price of share of shares converted			80.00%
Derivative liability			$ 2,400
Convertible Notes | Series C1 Redeemable Convertible Preferred Stock
Debt Instrument [Line Items]
Loan amount		9,500
Debt		$ 9,500
Number of stock issued upon conversion of convertible preferred stock | shares		10,351,063

Redeemable convertible prefer_3

Redeemable convertible preferred stock (Details) - USD ($) $ / shares in Units, $ in Thousands	Jul. 14, 2021	Jun. 25, 2021	Mar. 31, 2021	Apr. 30, 2020	Mar. 31, 2021	Jun. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jul. 19, 2021	Dec. 31, 2020	Mar. 31, 2020	Feb. 29, 2020	Dec. 31, 2019
Redeemable convertible preferred stock
Temporary equity share price (in dollars per share)							$ 0.01		$ 0.01	$ 0.01
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs							$ 79,743	$ 49,935
Preferred stock, authorized (in shares)							0		10,000,000	161,455,689
Peferred stock , par value (in shares)							$ 0.01		$ 0.01	$ 0.01
Preferred stock ,outstanding (in shares)			155,521,633		155,521,633	133,021,640	0	133,021,640		133,021,640	78,757,540		78,757,540
Convertible Notes
Redeemable convertible preferred stock
Long-term debt												$ 7,100
Series C1 And C2 Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock
Temporary equity share price (in dollars per share)				$ 1.15
Issuance costs				$ 600
Peferred stock , par value (in shares)				$ 1.15
Series C1 Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock
Shares issued				23,611,208		23,611,208
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs				$ 27,200
Preferred stock, authorized (in shares)										57,372,796
Preferred stock ,outstanding (in shares)										33,962,271
Series C1 Redeemable Convertible Preferred Stock | Convertible Notes
Redeemable convertible preferred stock
Number of stock issued upon conversion of convertible preferred stock				10,351,063
Long-term debt				$ 9,500
Series C2 Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock
Shares issued				20,301,829		20,301,829
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs				$ 23,300
Number of shares exchanged		11,437,301
Preferred stock, authorized (in shares)										20,301,829
Preferred stock ,outstanding (in shares)										20,301,829
Series D1 and D2 Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock
Temporary equity share price (in dollars per share)			$ 3.60		$ 3.60
Issuance costs			$ 2,700
Peferred stock , par value (in shares)			$ 3.60		$ 3.60
Series D1 Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock
Shares issued			22,086,725		22,086,725
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs			$ 79,500
Series D2 Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock
Shares issued			413,268		413,268
Proceeds from issuance of redeemable convertible preferred stock, net of issuance costs			$ 1,500
Number of shares exchanged		2,364,509
Common Class A
Redeemable convertible preferred stock
Conversion of Stock, Shares Issued	24,200,920
Common Class B
Redeemable convertible preferred stock
Conversion of Stock, Shares Issued	6,903,379

Redeemable convertible prefer_4

Redeemable convertible preferred stock - Preferred Stock (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Jul. 19, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Redeemable convertible preferred stock
Preferred stock authorized	0	10,000,000			161,455,689
Preferred stock issued	0				133,021,640
Preferred stock outstanding	0			155,521,633	133,021,640	133,021,640	133,021,640	78,757,540	78,757,540
Redeemable convertible preferred stock			$ 235,836	$ 233,832	$ 151,826	$ 149,552	$ 147,308	$ 83,456	$ 81,850
Liquidation preference					$ 204,808
Common stock issuable upon conversion					26,604,306
Series A1 Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock
Preferred stock authorized					22,563,639
Preferred stock issued					18,740,115
Preferred stock outstanding					18,740,115
Redeemable convertible preferred stock					$ 18,542
Liquidation preference					$ 21,176
Common stock issuable upon conversion					3,748,022
Series B1 Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock
Preferred stock authorized					61,217,425
Preferred stock issued					60,017,425
Preferred stock outstanding					60,017,425
Redeemable convertible preferred stock					$ 68,511
Liquidation preference					$ 90,026
Common stock issuable upon conversion					12,003,474
Series C1 Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock
Preferred stock authorized					57,372,796
Preferred stock issued					33,962,271
Preferred stock outstanding					33,962,271
Redeemable convertible preferred stock					$ 40,632
Liquidation preference					$ 58,585
Common stock issuable upon conversion					6,792,445
Series C2 Redeemable Convertible Preferred Stock
Redeemable convertible preferred stock
Preferred stock authorized					20,301,829
Preferred stock issued					20,301,829
Preferred stock outstanding					20,301,829
Redeemable convertible preferred stock					$ 24,141
Liquidation preference					$ 35,021
Common stock issuable upon conversion					4,060,365

Preferred stock warrants (Detai

Preferred stock warrants (Details) - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2020	May 31, 2020
2020 Term Loan | Series C1 Redeemable Convertible Preferred Stock
Class of Warrant or Right [Line Items]
Shares issued upon conversion of warrant		1,195,652
Exercise price		$ 1.15
Preferred stock warrant
Class of Warrant or Right [Line Items]
Warrant fair value	$ 4,117
Preferred stock warrant | Series C1 Redeemable Convertible Preferred Stock
Class of Warrant or Right [Line Items]
Exercise price		$ 1.15
Warrant expiry term		10 years
Warrant fair value		$ 700

Preferred stock warrants - Clas

Preferred stock warrants - Classes of Preferred Stock Outstanding (Details) - Preferred stock warrant - USD ($) $ / shares in Units, $ in Thousands	Dec. 31, 2020	May 31, 2020
Preferred stock warrants
Preferred shares issuable upon exercise of warrant	6,219,170
Warrant fair value	$ 4,117
Series A1 Redeemable Convertible Preferred Stock | Liability
Preferred stock warrants
Warrant expiry term	10 years
Preferred shares issuable upon exercise of warrant	3,823,524
Weighted average exercise price (in dollars per share)	$ 0.01
Warrant fair value	$ 1,875
Series B1 Redeemable Convertible Preferred Stock | Liability
Preferred stock warrants
Warrant expiry term	10 years
Preferred shares issuable upon exercise of warrant	1,199,994
Weighted average exercise price (in dollars per share)	$ 0.01
Warrant fair value	$ 1,501
Series C1 Redeemable Convertible Preferred Stock
Preferred stock warrants
Warrant expiry term		10 years
Weighted average exercise price (in dollars per share)		$ 1.15
Warrant fair value		$ 700
Series C1 Redeemable Convertible Preferred Stock | Liability
Preferred stock warrants
Warrant expiry term	10 years
Preferred shares issuable upon exercise of warrant	1,195,652
Weighted average exercise price (in dollars per share)	$ 1.15
Warrant fair value	$ 741

Common stock and common stock_3

Common stock and common stock warrants (Details) $ / shares in Units, $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2021USD ($)Vote$ / sharesshares	Dec. 31, 2020USD ($)$ / sharesshares	Jul. 19, 2021shares
Common stock and common stock warrants
Cash dividends | $	$ 0	$ 0
Shares reserved	9,991,141	32,574,029
Common Class A
Common stock and common stock warrants
Common stock, authorized (in shares)	210,000,000	35,000,000	210,000,000
Common stock, issued (in shares)	34,449,154	612,850
Common stock, outstanding (in shares)	34,449,154	612,850
Common stock, par value (in dollars per share) | $ / shares	$ 0.01	$ 0.01
Number of votes | Vote	1
Common Class B
Common stock and common stock warrants
Common stock, authorized (in shares)	10,000,000	0	10,000,000
Common stock, issued (in shares)	6,903,379	0
Common stock, outstanding (in shares)	6,903,379	0
Common stock, par value (in dollars per share) | $ / shares	$ 0.01	$ 0.01

Common stock and common stock_4

Common stock and common stock warrants - Warrants (Details) - Common stock and common stock warrant - $ / shares	Sep. 30, 2021	Dec. 31, 2020
Common stock and common stock warrants
Common stock shares issuable upon exercise of warrant	1,030,944	55,835
Equity | July 24, 2017
Common stock and common stock warrants
Contractual term (in years)	10 years	10 years
Common stock shares issuable upon exercise of warrant	25,835	25,835
Weighted average exercise price (in dollars per share)	$ 295.15	$ 295.15
Equity | April 12, 2018
Common stock and common stock warrants
Contractual term (in years)	10 years	10 years
Common stock shares issuable upon exercise of warrant	30,000	30,000
Weighted average exercise price (in dollars per share)	$ 1	$ 1
Equity | July 14, 2021
Common stock and common stock warrants
Contractual term (in years)	10 years
Common stock shares issuable upon exercise of warrant	975,109
Weighted average exercise price (in dollars per share)	$ 1.46

Stock-based compensation - 2010

Stock-based compensation - 2010 Stock Option and Grant Plan (Details) - shares	1 Months Ended	9 Months Ended
	Mar. 31, 2021	Sep. 30, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted		1,732,182
2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional shares authorized	382,889
Number of shares available for grant			4,945,783
Granted		0

Stock-based compensation - Weig

Stock-based compensation - Weighted Average Basis Assumptions (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Stock-based compensation
Risk-free interest rate	0.96%	0.34%	0.90%	0.36%
Expected term (in years)	5 years 9 months 18 days	6 years	6 years	6 years
Expected volatility	43.70%	90.40%	51.50%	90.30%
Expected dividend yield	0.00%	0.00%	0.00%	0.00%

Stock-based compensation - Stoc

Stock-based compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Number of shares
Outstanding as of December 31, 2020 (in shares)			3,604,584
Granted (in shares)			1,732,182
Exercised (in shares)			(111,149)
Expired (in shares)			(34,447)
Forfeited (in shares)			(667,866)
Outstanding as of September 30, 2021 (in shares)	4,523,304		4,523,304		3,604,584
Options vested and expected to vest as of September 30, 2021 (in shares)	4,523,304		4,523,304
Options exercisable as of September 30, 2021 (in shares)	2,134,381		2,134,381
Weighted average exercise price
Outstanding as of December 31, 2020 (in dollars per share)			$ 0.92
Granted (in dollars per share)			9.15
Exercised (in dollars per share)			2.67
Expired (in dollars per share)			1
Forfeited (in dollars per share)			2.12
Outstanding as of September 30, 2021 (in dollars per share)	$ 3.88		3.88		$ 0.92
Options vested and expected to vest as of September 30, 2021 (in dollars per share)	3.88		3.88
Options exercisable as of September 30, 2021 (in dollars per share)	$ 1.25		$ 1.25
Weighted average remaining contractual term
Weighted average remaining contractual term (in years)			7 years 8 months 4 days		8 years 1 month 13 days
Options vested and expected to vest (in years)			7 years 8 months 4 days
Options exercisable (in years)			6 years 2 months 1 day
Aggregate intrinsic value
Aggregate intrinsic value	$ 66,231		$ 66,231		$ 4,272
Options vested and expected to vest	66,231		66,231
Options exercisable	$ 36,777		$ 36,777
Exercised				$ 0
Weighted average grant-date fair value	$ 8.33	$ 0.55	$ 4.05	$ 0.55

Stock-based compensation - Rest

Stock-based compensation - Restricted Stock (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	9 Months Ended
	Feb. 28, 2021	Sep. 30, 2021	Dec. 31, 2020
Share-based compensation
Proceeds from issuance of restricted stock award		$ 523
Restricted Stock
Share-based compensation
Vesting Period	4 years
Proceeds from issuance of restricted stock award	$ 500
Number of shares
Granted (in shares)	248,903	248,903
Unvested as of September 30, 2021 (in shares)		248,903
Weighted average fair value
Granted (in dollars per share)	$ 2.10	$ 2.10
Unvested as of September 30, 2021 (in dollars per share)		$ 2.10
Restricted Stock | Other long-term liabilities
Share-based compensation
Amount of restricted common stock liability		$ 700	$ 0

Stock-Based compensation - St_2

Stock-Based compensation - Stock-Based Compensation Expense (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 31, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense		$ 584	$ 115	$ 1,165	$ 361
Unrecognized compensation expense		$ 6,200		$ 6,200
Weighted average period				1 year 4 months 24 days
2021 Incentive Award Plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Term of awards	10 years
Number of shares authorized	4,200,000
Threshold annual increase in shares available for issuance expressed as a percentage	5.00%
Maximum number of shares issuable upon exercise of stock option	33,900,000
Shares avaliable for issuance		4,187,990		4,187,990
2021 Employee Stock Purchase Plan
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Term of awards	10 years
Number of shares authorized	400,000
Threshold annual increase in shares available for issuance expressed as a percentage	1.00%
Maximum number of shares issuable upon exercise of stock option	6,300,000
Offering Period				$ 0
Cost of revenue
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense		$ 106	20	$ 221	62
General and administrative
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense		345	72	680	223
Sales and marketing
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense		76	11	158	42
Research and development
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Stock-based compensation expense		$ 57	$ 12	$ 106	$ 34

Net loss per share - Basic and

Net loss per share - Basic and Diluted Net Loss per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Net loss	$ (24,987)	$ (11,831)	$ (22,101)	$ (8,465)	$ (9,267)	$ (8,007)	$ (58,919)	$ (25,739)
Accretion of redeemable convertible preferred stock to redemption value	210			(832)			(1,761)	(2,882)
Cumulative redeemable convertible preferred stock dividends	(451)			(1,412)			(2,747)	(2,987)
Net loss attributable to common stockholders - basic	(25,228)			(10,709)			(63,427)	(31,608)
Net loss attributable to common stockholders - diluted	$ (25,228)			$ (10,709)			$ (63,427)	$ (31,608)
Denominator:
Weighted average common shares outstanding - basic	35,316,099			356,074			12,344,619	354,341
Weighted average common shares outstanding - diluted	35,316,099			356,074			12,344,619	354,341
Net loss per share attributable to common stockholders - basic	$ (0.71)			$ (30.08)			$ (5.14)	$ (89.20)
Net loss per share attributable to common stockholders - diluted	$ (0.71)			$ (30.08)			$ (5.14)	$ (89.20)
Common Class A
Denominator:
Weighted average common shares outstanding - basic	29,463,234			356,074			10,372,225	354,341
Weighted average common shares outstanding - diluted	29,463,234			356,074			10,372,225	354,341
Net loss per share attributable to common stockholders - basic	$ (0.71)			$ (30.08)			$ (5.14)	$ (89.20)
Net loss per share attributable to common stockholders - diluted	$ (0.71)			$ (30.08)			$ (5.14)	$ (89.20)
Common Class B
Denominator:
Weighted average common shares outstanding - basic	5,852,865						1,972,394
Weighted average common shares outstanding - diluted	5,852,865						1,972,394
Net loss per share attributable to common stockholders - basic	$ (0.71)						$ (5.14)
Net loss per share attributable to common stockholders - diluted	$ (0.71)						$ (5.14)

Net loss per share - Schedule o

Net loss per share - Schedule of Common Stock Excluded From Computation of Diluted Net Loss per Share (Details) - shares	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares from the computation of diluted net loss per share	5,067,172	31,909,593
Options to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares from the computation of diluted net loss per share	4,772,207	4,005,581
Warrants to purchase common stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares from the computation of diluted net loss per share	294,965	55,872
Redeemable convertible preferred stock
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares from the computation of diluted net loss per share		26,604,306
Warrants to purchase preferred stock (as converted to warrants to purchase common stock)
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common shares from the computation of diluted net loss per share		1,243,834

Commitments and contingencies -

Commitments and contingencies - Lease Agreements (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended		9 Months Ended
	Oct. 31, 2013	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021
Commitments and contingencies
Renewal term	5 years					5 years
Option to extend	true
Tenant improvement allowance	$ 0.7
Asset Retirement Obligations, Noncurrent						$ 0.2
Rent expense		$ 0.2	$ 0.1	$ 0.4	$ 0.3
Lease payments for furniture and equipment						$ 0.6

Commitments and contingencies_2

Commitments and contingencies - Future Minimum Lease Commitments under Operating Leases (Details) $ in Thousands	Sep. 30, 2021USD ($)
Year ending December 31,
2021	$ 169
2022	1,139
2023	1,169
2024	1,199
2025	1,229
Thereafter	2,997
Total	$ 7,902

Commitments and contingencies_3

Commitments and contingencies - Loan Exit Fee, Supply Agreement and Software Subscription (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2016
Loan exit fee
Long-term Purchase Commitment [Line Items]
Loan exit fee			$ 0.8
Obligation		$ 0
Loan exit fee | Minimum
Long-term Purchase Commitment [Line Items]
Percentage of common stock			50.00%
Supply arrangement
Long-term Purchase Commitment [Line Items]
Accrued liability	$ 0.3	0.1
Supply agreement
Accrued supply agreement amount	0.8
Software subscription
Long-term Purchase Commitment [Line Items]
Obligation	1.1
Accrued liability	$ 0	$ 0

Benefit plans (Details)

Benefit plans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Contributions made	$ 0.1		$ 0.2	$ 0.1
Maximum
Defined Benefit Plan Disclosure [Line Items]
Contributions made		$ 0.1