Backblaze (BLZE) 10-Q 14 Dec 21 2021 Q3 Quarterly report Financial data

Cover

Cover - shares shares in Millions	9 Months Ended
	Sep. 30, 2021	Nov. 30, 2021
Entity Information [Line Items]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 2021
Document Transition Report	false
Entity File Number	001-41026
Entity Registrant Name	BACKBLAZE, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	20-8893125
Entity Address, Address Line One	500 Ben Franklin Ct
Entity Address, City or Town	San Mateo
Entity Address, State or Province	CA
Entity Address, Postal Zip Code	94401
City Area Code	650
Local Phone Number	352-3738
Title of 12(b) Security	Class A Common Stock, $0.0001 par value per share
Trading Symbol	BLZE
Security Exchange Name	NASDAQ
Entity Current Reporting Status	No
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	0001462056
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q3
Amendment Flag	false
Common Class A
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		7.9
Common Class B
Entity Information [Line Items]
Entity Common Stock, Shares Outstanding		22.4

Condensed Balance Sheets

Condensed Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Current assets:
Cash and cash equivalents	$ 4,684	$ 6,076
Accounts receivable, net	115	209
Prepaid expenses and other current assets	4,004	2,947
Total current assets	8,803	9,232
Property and equipment, net	40,395	38,746
Capitalized internal-use software, net	7,719	5,682
Other assets	3,480	809
Total assets	60,397	54,469
Current liabilities:
Accounts payable	1,403	1,710
Accrued expenses and other current liabilities	4,089	3,596
Accrued value-added tax (“VAT”) liability	2,275	1,533
Capital lease liability and lease financing obligation, current	11,966	11,320
Deferred revenue, current	21,127	17,587
Debt, current	0	628
Total current liabilities	40,860	36,374
Capital lease liability and lease financing obligation, non-current	17,238	17,886
Deferred revenue, non-current	3,367	1,801
Other long-term liabilities	698	820
Simple agreement for future equity (“SAFE”) notes	10,359	0
Debt, non-current	0	1,644
Total liabilities	72,522	58,525
Commitments and contingencies (Note 10)
Convertible Preferred Stock
Convertible preferred stock, $0.001 par value; 9,000,000 shares authorized as of September 30, 2021 and December 31, 2020; 3,359,195 issued and outstanding with aggregate liquidation preference of $2,852 as of September 30, 2021 and December 31, 2020, respectively	2,784	2,784
Stockholders’ Deficit
Common stock, $0.001 par value; 36,000,000 shares authorized as of September 30, 2021 and December 31, 2020; 18,936,698 and 18,614,905 shares issued and outstanding as of September 30, 2021 and December 31, 2020, respectively	5	5
Additional paid-in capital	11,824	7,794
Accumulated deficit	(26,738)	(14,639)
Total stockholders’ deficit	(14,909)	(6,840)
Total liabilities, convertible preferred stock and stockholders’ deficit	$ 60,397	$ 54,469

Condensed Balance Sheets (Paren

Condensed Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Convertible Preferred Stock
Par value (USD per share)	$ 0.001	$ 0.001
Shares authorized (in shares)	9,000,000	9,000,000
Shares issued (in shares)	3,359,195	3,359,195
Shares outstanding (in shares)	3,359,195	3,359,195
Aggregate liquidation preference	$ 2,852	$ 2,852
Stockholders’ Deficit
Par value (USD per share)	$ 0.001	$ 0.001
Shares authorized (in shares)	36,000,000	36,000,000
Shares issued (in shares)	18,936,698	18,614,905
Shares outstanding (in shares)	18,936,698	18,614,905

Condensed Statement of Operatio

Condensed Statement of Operations - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Statement [Abstract]
Revenue	$ 17,320	$ 13,817	$ 48,782	$ 39,196
Cost of revenue	8,519	7,097	24,275	18,775
Gross profit	8,801	6,720	24,507	20,421
Operating expenses:
Research and development	5,338	3,300	14,314	9,132
Sales and marketing	5,025	2,956	13,149	8,379
General and administrative	3,104	1,519	8,261	4,157
Total operating expenses	13,467	7,775	35,724	21,668
Loss from operations	(4,666)	(1,055)	(11,217)	(1,247)
Interest expense	(968)	(793)	(2,686)	(1,946)
Gain on extinguishment of debt	0	0	2,299	0
Unrealized loss on SAFE	(359)	0	(359)	0
Loss before provision for income taxes	(5,993)	(1,848)	(11,963)	(3,193)
Income tax provision	0	(12)	(136)	(12)
Net loss	$ (5,993)	$ (1,860)	$ (12,099)	$ (3,205)
Net loss per share, basic (USD per share)	$ (0.32)	$ (0.10)	$ (0.64)	$ (0.17)
Net loss per share, diluted (USD per share)	$ (0.32)	$ (0.10)	$ (0.64)	$ (0.17)
Weighted average shares used in computing net loss per share, basic (in shares)	18,936,698	18,614,869	18,775,908	18,607,705
Weighted average shares used in computing net loss per share, diluted (in shares)	18,936,698	18,614,869	18,775,908	18,607,705

Condensed Statement of Changes

Condensed Statement of Changes in Convertible Preferred Stock and Stockholders' Deficit - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Deficit	Cumulative Effect, Period of Adoption, Adjustment	Cumulative Effect, Period of Adoption, AdjustmentAccumulated Deficit
Beginning balance (in shares) at Dec. 31, 2019	3,359,195
Beginning balance at Dec. 31, 2019	$ 2,784
Ending balance (in shares) at Sep. 30, 2020	3,359,195
Ending balance at Sep. 30, 2020	$ 2,784
Beginning balance (in shares) at Dec. 31, 2019		18,596,772
Beginning balance at Dec. 31, 2019	(2,594)	$ 5	$ 5,684	$ (8,283)	$ 267	$ 267
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(3,205)			(3,205)
Issuance of common stock upon exercise of stock options (in shares)		18,097
Issuance of common stock upon exercise of stock options	19		19
Stock-based compensation	1,373		1,373
Ending balance (in shares) at Sep. 30, 2020		18,614,869
Ending balance at Sep. 30, 2020	$ (4,140)	$ 5	7,076	(11,221)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Accounting Standards Update [Extensible Enumeration]	Accounting Standards Update 2014-09 [Member]
Beginning balance (in shares) at Jun. 30, 2020	3,359,195
Beginning balance at Jun. 30, 2020	$ 2,784
Ending balance (in shares) at Sep. 30, 2020	3,359,195
Ending balance at Sep. 30, 2020	$ 2,784
Beginning balance (in shares) at Jun. 30, 2020		18,614,869
Beginning balance at Jun. 30, 2020	(2,804)	$ 5	6,552	(9,361)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(1,860)			(1,860)
Stock-based compensation	524		524
Ending balance (in shares) at Sep. 30, 2020		18,614,869
Ending balance at Sep. 30, 2020	$ (4,140)	$ 5	7,076	(11,221)
Beginning balance (in shares) at Dec. 31, 2020	3,359,195
Beginning balance at Dec. 31, 2020	$ 2,784
Ending balance (in shares) at Sep. 30, 2021	3,359,195
Ending balance at Sep. 30, 2021	$ 2,784
Beginning balance (in shares) at Dec. 31, 2020	18,614,905	18,614,905
Beginning balance at Dec. 31, 2020	$ (6,840)	$ 5	7,794	(14,639)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	$ (12,099)			(12,099)
Issuance of common stock upon exercise of stock options (in shares)	321,793	321,793
Issuance of common stock upon exercise of stock options	$ 148		148
Stock-based compensation	$ 3,882		3,882
Ending balance (in shares) at Sep. 30, 2021	18,936,698	18,936,698
Ending balance at Sep. 30, 2021	$ (14,909)	$ 5	11,824	(26,738)
Beginning balance (in shares) at Jun. 30, 2021	3,359,195
Beginning balance at Jun. 30, 2021	$ 2,784
Ending balance (in shares) at Sep. 30, 2021	3,359,195
Ending balance at Sep. 30, 2021	$ 2,784
Beginning balance (in shares) at Jun. 30, 2021		18,936,698
Beginning balance at Jun. 30, 2021	(10,521)	$ 5	10,219	(20,745)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(5,993)			(5,993)
Stock-based compensation	$ 1,605		1,605
Ending balance (in shares) at Sep. 30, 2021	18,936,698	18,936,698
Ending balance at Sep. 30, 2021	$ (14,909)	$ 5	$ 11,824	$ (26,738)

Condensed Statements of Cash Fl

Condensed Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
CASH FLOWS FROM OPERATING ACTIVITIES
Net loss	$ (12,099)	$ (3,205)
Adjustments to reconcile net loss to net cash provided by operating activities:
Gain on extinguishment of Paycheck Protection Program (“PPP”) loan	(2,299)	0
Unrealized loss on SAFE	359	0
Depreciation and amortization	12,041	9,111
Stock-based compensation	3,611	1,214
Amortization of deferred contract costs	579	489
(Gain) loss on disposal of assets and other	(17)	12
Changes in operating assets and liabilities:
Accounts receivable	94	(11)
Prepaid expenses and other current assets	(1,985)	(1,546)
Other assets	(256)	272
Accounts payable	(258)	(449)
Accrued expenses and other current liabilities	444	1,297
Accrued VAT liability	742	43
Deferred revenue	5,105	1,743
Other long-term liabilities	(97)	596
Net cash provided by operating activities	5,964	9,566
CASH FLOWS FROM INVESTING ACTIVITIES
Proceeds from disposal of property and equipment	17	0
Purchases of property and equipment, net	(6,893)	(1,776)
Capitalized internal-use software costs	(3,013)	(2,163)
Net cash used in investing activities	(9,889)	(3,939)
CASH FLOWS FROM FINANCING ACTIVITIES
Principal payments on capital lease and lease financing obligations	(8,715)	(7,701)
Payments of deferred offering costs	(1,807)	0
Proceeds from PPP	0	2,272
Proceeds from SAFE	10,000	0
Proceeds from lease financing	2,907	0
Proceeds from exercises of stock options	148	19
Net cash provided by (used in) financing activities	2,533	(5,410)
Net (decrease) increase in cash and cash equivalents	(1,392)	217
Cash and cash equivalents at beginning of period	6,076	6,978
Cash and cash equivalents at end of period	4,684	7,195
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid for interest	2,578	1,955
SUPPLEMENTAL DISCLOSURE OF NON-CASH INVESTING AND FINANCING ACTIVITIES
Stock-based compensation capitalized internal-use software	271	159
Equipment acquired through capital lease obligations	8,895	20,538
Accruals related to purchases of property and equipment	250	4
Extinguishment of PPP loan	$ 2,299	$ 0

Organization and Description of

Organization and Description of Business	9 Months Ended
	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization and Description of Business	Organization and Description of Business Description of Business Backblaze, Inc. (“Backblaze” or the “Company”) is a storage cloud platform, providing businesses and consumers with solutions to store and use their data. Backblaze provides these cloud services through purpose-built, web-scale software built on commodity hardware. Backblaze was incorporated in the state of Delaware on April 20, 2007 and is headquartered in San Mateo, California.

Basis of Presentation and Summa

Basis of Presentation and Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation and Summary of Significant Accounting Policies	Basis of Presentation and Summary of Significant Accounting Policies Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (the “SEC”) regarding interim financial reporting. Accordingly, they do not include all disclosures normally required in annual financial statements prepared in accordance with GAAP. Therefore, these unaudited condensed financial statements should be read in conjunction with the audited financial statements and notes included in the Company’s final prospectus dated November 10, 2021 and filed with the SEC pursuant to Rule 424(b)(4) on November 12, 2021 (“Final Prospectus”). In management’s opinion, these unaudited condensed financial statements have been prepared on the same basis as the annual financial statements and 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, results of operations for the three and nine months ended September 30, 2021 and 2020, cash flows for the nine months ended September 30, 2021 and 2020, and stockholders' deficit for the three and nine months ended September 30, 2021 and 2020. The results of operations for the three and nine months ended September 30, 2021 and 2020 are not necessarily indicative of the results to be expected for the full year or any other future interim or annual period. Stock Split During October 1, 2021, the Company effected a 3.6-for-1 stock split of its outstanding common stock and convertible preferred stock. Upon the effectiveness of the stock split, all issued and outstanding shares of common stock and convertible preferred stock and related per share amounts contained in the accompanying financial statements were retroactively revised to reflect this stock split for all periods presented. The par value of the authorized stock was not adjusted as a result of the stock split. Emerging Growth Company The Company is an emerging growth company (“EGC”), as defined in the Jumpstart Our Business Startups Act of 2012 (the “JOBS Act”). Under the JOBS Act, EGCs can delay adopting new or revised accounting standards issued subsequent to the enactment of the JOBS Act until such time as those standards apply to private companies. The Company has elected to use this extended transition period for complying with new or revised accounting standards that have different effective dates for public and private companies until the earlier of the date that it (i) is no longer an EGC or (ii) affirmatively and irrevocably opts out of the extended transition period provided in the JOBS Act. As a result, these financial statements may not be comparable to companies that comply with the new or revised accounting pronouncements as of public company effective dates. The Company expects to use the extended transition period for any other new or revised accounting standards during the period in which it remains an EGC. Segment Information The Company has a single operating and reportable segment. In reaching this conclusion, management considers the definition of the chief operating decision maker (“CODM”), how the business is defined by the CODM, the nature of the information provided to the CODM and how that information is used to make operating decisions, allocate resources and assess performance. The Company’s chief operating decision maker is its Chief Executive Officer, who reviews financial information presented on an aggregated basis for purposes of making operating decisions, assessing financial performance and allocating resources. Significant accounting policies The Company’s significant accounting policies are disclosed in the Company’s audited financial statements and related notes thereto included in the Final Prospectus. There have been no changes to these accounting policies. Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported and disclosed in the financial statements and the accompanying notes. Such estimates and assumptions include the costs to be capitalized as internal-use software and their useful life, the useful lives of other long-lived assets, impairment considerations for long-lived assets, expected lease term for capital leases, calculation of the refund liability, estimates related to variable consideration, valuation of the Company’s common stock and stock options and accounting for taxes, including estimates for sales tax and VAT liability, deferred tax assets, valuation allowance and uncertain tax positions. The Company bases its estimates on historical experience and on assumptions that management considers reasonable. Future actual results could differ materially from these estimates. Risks and Uncertainties COVID-19 The worldwide spread of coronavirus and its variants including delta and omicron (“COVID-19”) have created significant uncertainty in the global economy. There have been no comparable recent events that provide guidance as to the effect the spread of COVID-19 as a global pandemic may have, and as a result, the ultimate impact of COVID-19 and the extent to which COVID-19 continues to impact Backblaze’s business will depend on future developments, which are highly uncertain and difficult to predict. While the full impact of the pandemic to the business remains unknown and Backblaze does not believe that its results of operations and financial condition have been materially adversely impacted as of the date of these financial statements, Backblaze also believes that the pandemic has had some impact on its business. The Company’s potential customers, customers, supply chain or partners may have experienced, or in the future could experience, downturns or uncertainty in their own business operations due to COVID-19, which may have affected or could affect purchasing and operating decisions. For example, although Backblaze believes its ability to retain customers has not been materially impacted by the pandemic, Backblaze also believes that the pandemic may have caused some customers to reduce their use of cloud storage with Backblaze or to delay increasing their use of Backblaze’s cloud storage offerings. In addition, the pandemic may have caused potential customers to delay their purchasing decisions or to store less data with Backblaze. The Company may experience customer losses due to customer bankruptcy or cessation of operations, or other factors. In addition, the Company’s supply chain may be disrupted, or it may be unable to obtain infrastructure and related equipment essential to its business on favorable terms or at all. The Company does not yet know the full extent of potential impacts on its business or operations or on the global economy as a whole, particularly if the COVID-19 pandemic continues and persists for an extended period of time. As of the date of these financial statements, the Company is not aware of any specific event or circumstance that would require it to update its estimates, judgments or the carrying value of its assets or liabilities. Concentrations Credit risk. Financial instruments that potentially subject the Company to credit risk primarily consist of cash, cash equivalents and accounts receivable. The Company maintains its cash and cash equivalents with high-quality financial institutions with investment-grade ratings. Deposits with these financial institutions may exceed the amount of insurance provided on such deposits. For accounts receivable, the Company is exposed to credit risk in the event of nonpayment by customers to the extent of the amount recorded on the condensed balance sheets. Vendors. The Company acquires infrastructure equipment from third-party vendors. Vendors may have limited sources of equipment and supplies which may expose the Company to potential supply and service disruptions that could harm the Company’s business. Two vendors represented in aggregate 31% of total cash disbursements during the year ended December 31, 2020, while three vendors represented 20% of the accounts payable balance as of December 31, 2020. Two vendors represented an aggregate 25% of total cash disbursements during the nine months ended September 30, 2021, while three vendors represented an aggregate 45% of the accounts payable balance as of September 30, 2021. Revenue. The Company derives substantially all of its revenue from the services operating on its Backblaze Storage Cloud platform: its Backblaze B2 Cloud Storage (“Backblaze B2”) and Backblaze Computer Backup (“Computer Backup”) offerings. The potential for severe impact to the Company’s business could result if the Company was unable to operate its platform or serve customers through its platform for an extended period of time. Accounting Pronouncements Not Yet Adopted In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-02, Leases (Topic 842 ), which requires the recognition of lease assets and lease liabilities arising from operating leases on the balance sheet. Subsequently, the FASB also issued a series of amendments to this new lease standard that address the transition methods available and clarify the guidance for lessor costs and other aspects of the new lease standard. The Company will adopt the standard effective January 1, 2022 and expects to adopt using the modified retrospective transition method without restating comparative periods. The Company is currently evaluating the impact of the adoption of this guidance on its financial statements. In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires a financial asset measured at amortized cost basis to be presented at the net amount expected to be collected, with further clarifications made more recently. For trade receivables, loans and other financial instruments, the Company will be required to use a forward-looking expected loss model rather than the incurred loss model for recognizing credit losses which reflects losses that are probable. Credit losses relating to available-for-sale debt securities are required to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. This guidance is effective for the Company for its fiscal year beginning January 1, 2023 and interim periods within that fiscal year. The Company is currently evaluating the impact of the adoption of this guidance on its financial statements. In August 2018, the FASB issued ASU No. 2018-15, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40), which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by this new guidance. This new guidance is effective for the Company for its fiscal year beginning January 1, 2021 and interim periods within its fiscal year beginning January 1, 2022. Early adoption is permitted. The Company plans to adopt this guidance prospectively and does not expect the adoption of this guidance will have a material impact on its financial statements for the fiscal year ended December 31, 2021. In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes by eliminating some exceptions to the general approach in ASC 740, Income Taxes, in order to reduce cost and complexity of its application. This new guidance is effective for the Company for its fiscal year beginning January 1, 2022 and interim periods within its fiscal year beginning January 1, 2023. Early adoption is permitted. The Company is currently evaluating the impact of the adoption of this guidance on its financial statements.

Revenues

Revenues	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Revenues	Revenues Deferred Contract Costs The Company’s amortization of deferred contract costs was $0.2 million and $0.6 million for the three and nine months ended September 30, 2021, respectively, and was $0.2 million and $0.5 million during the three and nine months ended September 30, 2020, respectively. The amount of capitalized contract costs was $0.4 million as of September 30, 2021 and December 31, 2020. Deferred Revenue Deferred revenue was $24.5 million and $19.4 million as of September 30, 2021 and December 31, 2020, respectively. Revenue recognized during the three months ended September 30, 2021 and 2020 was approximately $7.6 million and $6.8 million, respectively, and approximately $15.6 million and $13.8 million during the nine months ended September 30, 2021 and 2020, respectively, which was included in each deferred revenue balance at the beginning of each respective period. The Company’s deferred revenue as stated on the condensed balance sheets presented approximate its contract liability balance as of September 30, 2021 and December 31, 2020. Disaggregation of Revenues The following table presents the Company’s revenues disaggregated by timing of revenue recognition (in thousands): For the Three Months Ended September 30, For the Nine Months Ended September 30, 2021 2020 2021 2020 Consumption-based arrangements (B2 Cloud Storage) $ 5,977 $ 3,757 $ 16,026 $ 10,018 Subscription-based arrangements (Computer Backup) 11,163 9,894 32,219 28,696 Physical Media 180 166 537 482 Total revenue $ 17,320 $ 13,817 $ 48,782 $ 39,196 The Company’s consumption-based arrangements are from its Backblaze B2 offering, and its subscription-based arrangements are from its Computer Backup offering. The Company’s management and CODM reviews revenue on the basis presented above. Revenue by geographic area, based on the location of the Company’s customers, was as follows (in thousands): For the Three Months Ended September 30, For the Nine Months Ended September 30, 2021 2020 2021 2020 United States $ 12,435 $ 9,960 $ 35,083 $ 28,469 Other 4,885 3,857 13,699 10,727 Total $ 17,320 $ 13,817 $ 48,782 $ 39,196

Cash Equivalents

Cash Equivalents	9 Months Ended
	Sep. 30, 2021
Cash and Cash Equivalents [Abstract]
Cash Equivalents	Cash EquivalentsThe Company’s cash equivalents on its condensed balance sheets included money market funds with an amortized cost and estimated fair value of less than $0.1 million and $2.7 million as of September 30, 2021 and December 31, 2020, respectively. The Company had no debt or equity investment securities during the nine months ended September 30, 2021 and 2020.

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The following table presents the fair value hierarchy for the Company’s assets and liabilities measured at fair value on a recurring basis as of September 30, 2021 and as of December 31, 2020 (in thousands): Level 1 Level 2 Level 3 September 30, December 31, September 30, December 31, September 30, December 31, Assets Cash equivalents: Money market funds $ 44 $ 2,651 $ — $ — $ — $ — Total $ 44 $ 2,651 $ — $ — $ — $ — Liabilities SAFE notes $ — $ — $ — $ — $ 10,359 $ — Total $ — $ — $ — $ — $ 10,359 $ — Fair values determined by Level 1 inputs utilize unadjusted quoted prices in active markets for identical assets. Level 3 instruments are characterized by unobservable inputs that are supported by little or no market activity, which require management judgment or estimation. The fair value of the SAFE notes was determined as of September 30, 2021 using unobservable inputs. In valuing the SAFE notes, the Company used a Monte Carlo simulation to forecast a range of probability-weighted settlement paths in combination with income, market, and cost-based valuation approaches. The settlement paths used probabilities ranging from 5% to 65%. The Company used a discount rate of approximately 30% to adjust the probability-weighted settlement paths to their present value. An increase in the discount rate would decrease the fair value of the instrument, and an increase in probabilities of certain settlement paths would increase the fair value of the instrument. The following table summarizes the total carrying value of the Company’s Level 3 instruments held as of September 30, 2021 including cumulative unrealized gains and losses recognized during the nine months ended September 30, 2021 (in thousands): Nine Months Ended September 30, 2021 Beginning balance as of December 31, 2020 $ — Sale of SAFE notes 10,000 Total unrealized loss 359 Ending balance as of September 30, 2021 $ 10,359

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	9 Months Ended
	Sep. 30, 2021
Prepaid Expense and Other Assets, Current [Abstract]
Prepaid Expenses and Other Current Assets	Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following (in thousands): September 30, December 31, Unbilled accounts receivable $ 1,150 $ 841 Prepaid expenses 633 643 Prepaid subscriptions 547 276 Capitalized commissions 343 315 Receivable from payment processor 468 268 Prepaid flash drives 347 — Prepaid data migration fees 103 71 Deposits 179 19 Other 234 514 Total prepaid expenses and other current assets $ 4,004 $ 2,947

Property and Equipment, Net

Property and Equipment, Net	9 Months Ended
	Sep. 30, 2021
Property, Plant and Equipment [Abstract]
Property and Equipment, Net	Property and Equipment, Net Property and equipment, net consisted of the following (in thousands): September 30, December 31, Data center equipment $ 11,053 $ 10,538 Leased data center equipment 58,826 51,852 Machinery and equipment 7,055 4,369 Computer equipment 1,496 1,176 Leasehold improvements 900 876 Construction-in-process 167 2,358 Total property and equipment 79,497 71,169 Less: accumulated depreciation (39,102) (32,423) Total property and equipment, net $ 40,395 $ 38,746

Capitalized_Internal-use_Softwa

Capitalized Internal-use Software, Net	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Capitalized Internal-use Software, Net	Capitalized Internal-use Software, Net Capitalized internal-use software, net consisted of the following (in thousands): September 30, December 31, Developed software $ 11,476 $ 8,593 Software purchased for internal-use 870 466 Total capitalized internal-use software 12,346 9,059 Less: accumulated amortization (4,627) (3,377) Total capitalized internal-use software, net $ 7,719 $ 5,682 Amortization expense of capitalized internal-use software was $0.4 million and $1.2 million for the three and nine months ended September 30, 2021, respectively, and was $0.3 million and $0.9 million for the three and nine months ended September 30, 2020, respectively. Amortization of developed software and software purchased for internal use are included in cost of revenue and general and administrative expense, respectively, in the Company’s statements of operations. As of September 30, 2021, future amortization expense is expected to be as follows (in thousands): Year Ending December 31, Remainder of 2021 $ 500 2022 1,998 2023 1,833 2024 1,569 2025 1,102 Thereafter 717 Total $ 7,719

Accrued Expenses and Other Curr

Accrued Expenses and Other Current Liabilities	9 Months Ended
	Sep. 30, 2021
Payables and Accruals [Abstract]
Accrued Expenses and Other Current Liabilities	Accrued Expenses and Other Current Liabilities Accrued expenses and other current liabilities consisted of the following (in thousands): September 30, December 31, Accrued compensation $ 1,125 $ 1,295 Accrued expenses 1,488 1,284 Accrued sales tax 977 598 Accrued income tax 141 5 Other 358 414 Accrued expenses and other current liabilities $ 4,089 $ 3,596

Commitment and Contingencies

Commitment and Contingencies	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Capital Leases The Company enters into capital lease arrangements to obtain hard drives and related equipment for its data center operations. The term of these agreements primarily range from three For the Company’s assets acquired through capital lease agreements, depreciation expense was $3.0 million and $8.9 million for the three and nine months ended September 30, 2021, respectively, and was $2.1 million and $6.4 million for the three and nine months ended September 30, 2020, respectively. Depreciation expense on the Company’s capital leases is included in cost of revenue in its statements of operations. There have been no material changes to the Company’s capital lease commitments during the nine months ended September 30, 2021. During the nine months ended September 30, 2021, the Company entered into two sale-leaseback arrangements with vendors to provide approximately $2.9 million in cash proceeds for previously purchased hard drives and related equipment. The Company concluded the related lease arrangements would be classified as lease financing obligations as it has the option to repurchase the assets at their fair value at a future date. Therefore, the transaction was deemed a failed sale-leaseback and was accounted for as a financing arrangement. The assets continue to be depreciated over their useful lives, and payments are allocated between interest expense and repayment of the financing liability. As of September 30, 2021, the future minimum payments related to the lease agreements consisted of the following (in thousands): Year Ending December 31, Remainder of 2021 $ 212 2022 848 2023 848 2024 840 2025 387 Thereafter — Total $ 3,135 Operating Leases The Company leases its facilities for data centers and office space under non-cancelable operating leases with various expiration dates. Certain lease agreements include options to renew or terminate the lease, which are not reasonably certain to be exercised and therefore are not factored into the determination of lease payments. Contingent rental payments are generally not included in the Company’s lease agreements. There have been no material changes to the Company’s operating lease commitments during the nine months ended September 30, 2021. Rental expense related to the Company’s operating leases was approximately $1.9 million and $5.1 million for the three and nine months ended September 30, 2021, respectively, and was $1.5 million and $3.9 million during the three and nine months ended September 30, 2020, respectively. Rental expense related to the Company’s operating leases is primarily included in cost of revenue in its condensed statements of operations. Other Contractual Commitments Other non-cancellable commitments relate mainly to infrastructure agreements used to facilitate the Company’s operations. As of September 30, 2021, the Company had non-cancelable purchase commitments of $0.6 million and $0.3 million payable during the years ending December 31, 2021 and 2022, respectively. 401(k) Plan The Company sponsors a 401(k) defined contribution plan covering all eligible U.S. employees. Contributions to the 401(k) plan are discretionary. The Company expensed $0.3 million and $0.8 million during the three and nine months ended September 30, 2021, respectively, and $0.2 million and $0.5 million during the three and nine months ended September 30, 2020, respectively, related to its 401(k) plan contributions. Legal Matters The Company is involved from time to time in various claims and legal actions arising in the ordinary course of business. While it is not feasible to predict or determine the ultimate outcome of these matters, the Company believes that none of its current legal proceedings will have a material adverse effect on its financial position, results of operations or cash flows. However, the results of legal proceedings are inherently unpredictable and if an unfavorable ruling were to occur in any of the current legal proceedings, there exists the possibility of a material adverse effect on the Company’s financial position, results of operations and cash flows. Sales Tax The Company undertook an analysis of its sales tax exposure based on the South Dakota vs. Wayfair case whereby the U.S. Supreme Court determined that physical presence was not required to determine the potential exposure a company has for sales tax purposes. Based on the Company’s analysis, its total accrual for sales tax payable was $1.0 million and $0.6 million as of September 30, 2021 and December 31, 2020, respectively, which includes estimated amounts for penalties and interest. Accrued VAT Liability The Company has calculated a liability for uncollected and unpaid VAT, which is generally assessed by various taxing authorities on services the Company provides to its customers. The Company accrues an amount that it considers probable to be collected and can be reasonably estimated. Based on the Company’s analysis, its total accrual for VAT tax payable was $2.3 million and $1.5 million as of September 30, 2021 and December 31, 2020, respectively, which includes estimated amounts for penalties and interest. Indemnification

Debt

Debt	9 Months Ended
	Sep. 30, 2021
Debt Disclosure [Abstract]
Debt	Debt Credit Facility On October 11, 2017, the Company entered into a $15.0 million revolving credit agreement with HomeStreet Bank. Under this agreement, amounts available to be borrowed are based on the lesser of $15.0 million or the Company’s trailing four month’s monthly recurring revenue multiplied by a retention rate as defined in the agreement. Advances on the line of credit bear interest payable monthly at the Wall Street Journal prime rate plus 0.25%. Borrowings are secured by substantially all of the Company’s assets, with limited exceptions. As of December 31, 2020, the Company was in compliance with covenants under the agreement. During April 2021 , the Company amended its revolving credit agreement. Under this amendment, among other things, (i) amounts available to be borrowed are based on the lesser of $10.0 million or the Company’s trailing four months monthly recurring revenue multiplied by a retention rate set forth in the amendment and (ii) advances on the line of credit bear interest payable monthly at the Wall Street Journal prime rate plus 1.00%. The revolving credit agreement, as amended, matures on June 1, 2022. As of September 30, 2021, no amounts were outstanding and the Company was in compliance with covenants under the agreement. During October 2021, in connection with entering into a revolving credit agreement with City National Bank, the Company subsequently terminated its agreement with HomeStreet Bank. See Note 16 Subsequent Events . Paycheck Protection Program On April 22, 2020 , the Company received approximately $2.3 million in funding through the U.S. Small Business Administration’s Paycheck Protection Program that was part of the CARES Act that was signed into law in March 2020. The interest rate on the loan was 1.00% per year and matured on April 2022. The note was payable in monthly installments of principal and interest, beginning in August 2021. The note was able to be repaid at any time with no payment penalty. The application for these funds required the Company to, in good faith, certify that the current economic uncertainty made the loan request necessary to support the ongoing operations of the Company. An application to forgive the entire amount was submitted with the lender in July 2020. Any request for forgiveness is subject to review and approval by the lender and the SBA. Further, the SBA has stated that all PPP loans in excess of $2.0 million, and other PPP loans as appropriate, will be subject to review by the SBA for compliance with program requirements. If the SBA determines in the course of its review that a borrower lacked an adequate basis for the required certification concerning the necessity of the loan request or the subsequent use of loan proceeds, the SBA will seek repayment of the PPP loan, including interest and potential penalties. The Company recognized the entire loan amount as a financial liability, with interest accrued and expensed over the term of the loan. In June 2021, the Company received notification from the SBA that the Company’s forgiveness application of the PPP loan and accrued interest, totaling $2.3 million, was approved in full, and the Company has no further obligations related to the PPP loan. Accordingly, the Company recorded the forgiveness of the PPP loan as gain on extinguishment of debt on its statement of operations. While the Company believes its loan was properly obtained and forgiven, there can be no assurance regarding the outcome of an SBA review. The Company has not been informed that a review will occur and has not accrued any liability associated with the risk of an adverse SBA review. Convertible notes and related party transactions During August 2021, the Company issued investors convertible notes (the “Security”) in the amount of $10.0 million . The Security is classified as a Simple Agreement for Future Equity agreement (“SAFE”). The convertible notes are automatically convertible into shares of the Company’s Class A common stock upon the completion of an initial public offering (or other liquidity event if sooner) at a discounted price to the value of its common stock at the time of such event. The discount shall initially be equal to 10% and shall increase by an additional 10% annually following the effective date, subject to a maximum discount of 50%. The discount shall be adjusted pro-rata on a monthly basis, increasing on the monthly anniversary of the effective date of the agreement. Interest shall accrue at the simple rate of 5% per annum of the outstanding amount commencing upon the effective date of the agreement and continuing until the outstanding principal amount has been paid in full or converted. The accrued interest shall be added to the purchased amount upon conversion into equity. If there is a change of control event, these SAFEs will automatically convert into the securities offered in connection with such change of control event. The Company determined that the SAFE notes should be classified as a liability based on evaluating the characteristics of the instrument, which contained both debt and equity-like features. As such, the Company has recorded the carrying value of the SAFE notes and the associated accrued interest as a current liability on its balance sheet as of September 30, 2021. As the SAFE notes were deemed to be a liability, the Company conducted a valuation of the SAFE notes liability as of September 30, 2021, which resulted in an unrealized loss of $0.4 million that the Company recorded in its condensed statement of operations.

Stockholders' Deficit

Stockholders' Deficit	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Stockholders' Deficit	Stockholders’ Deficit Common Stock. The Company has one class of common stock. The common stock is entitled to one vote per share. Holders of common stock are entitled to receive any dividends as may be declared from time to time by the Board of Directors. Common stock is subordinate to the convertible preferred stock with respect to dividend rights and rights upon certain deemed liquidation events. The Company had reserved shares of common stock for future issuance as follows: September 30, December 31, Convertible preferred stock 3,359,195 3,359,195 2011 Equity Incentive Plan Options outstanding 13,818,295 11,409,736 Shares available for future grants 114,987 865,339 Total 17,292,477 15,634,270 Equity Incentive Plan. In 2011, the Company’s Board approved the adoption of the 2011 Stock Plan (the “Plan”). The Plan provides for the grant of stock-based awards to employees, non-employee directors and other service providers of the Company. During May 2019 , the Company’s Board approved an increase to the number of authorized shares under the Plan by 1,800,000. Following the increase, the Plan had 9,720,000 shares authorized as of December 31, 2019. During April 2020 , the Company’s Board approved an increase to the number of authorized shares under the Plan by 2,700,000. Following the increase, the Plan had 12,420,000 shares authorized as of December 31, 2020. During March 2021, the Company’s Board approved an increase to the number of authorized shares under the Plan by 1,800,000. Following the increase, the Plan had 14,220,000 shares authorized. During August 2021, the Company’s Board approved an increase to the number of authorized shares under the 2011 Stock Plan by 180,000. Following the increase, the 2011 Stock Plan had 14,400,000 shares authorized as of September 30, 2021. Stock Options. Stock options granted under the Plan generally vest based on continued service over four years and expire ten years from the date of grant. A summary of stock option activity under the Plan and related information is as follows (in thousands, except share, price and year data): Shares Outstanding Weighted- Weighted- Aggregate Balance as of December 31, 2020 865,339 11,409,736 $ 2.27 6.52 $ 36,889 Shares authorized 1,980,000 Granted (2,994,120) 2,994,120 7.16 Exercised — (321,793) 0.61 Cancelled 263,768 (263,768) 3.54 Balance as of September 30, 2021 114,987 13,818,295 $ 3.35 6.69 $ 169,042 Vested and exercisable as of September 30, 2021 8,110,364 $ 2.05 4.97 $ 109,769 The weighted-average grant-date fair value of options granted was $5.39 and $1.84 during the nine months ended September 30, 2021 and 2020, respectively. The intrinsic value of options exercised for the nine months ended September 30, 2021 and 2020 was $4.8 million and less than $0.1 million, respectively. The aggregate grant-date fair value of options vested was $2.5 million and $1.1 million during the nine months ended September 30, 2021 and 2020, respectively. Aggregate intrinsic value represents the difference between the exercise price of the options and the estimated fair value of the Company’s common stock. In June 2021, the Company issued full-recourse promissory notes to four employees of the Company for an aggregate principal amount of $48 thousand with an interest rate of 0.13% per annum. All of the principal was used to exercise options for 234,526 shares of the Company’s common stock. As of September 30, 2021 , the Company has accounted for the notes as a deduction from stockholders’ deficit. Following the Company’s initial public offering (“IPO”), these notes matured in November 2021, in connection with the sale of the underlying shares by these employees.

Stock-Based Compensation

Stock-Based Compensation	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Stock-Based Compensation	Stock-Based Compensation The following table summarizes the Black-Scholes option pricing model weighted-average assumptions used in estimating the fair value of stock options granted to employees during the three months ended September 30, 2021, and during the nine months ended September 30, 2021 and 2020. No options grants were made during the three months ended September 30, 2020. Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Expected term (in years) 6.0 — 6.0 6.0 Expected volatility 48.8 % — % 49.1 % 48.5 % Risk-free interest rate 0.93 % — % 1.05 % 0.41 % Expected term. For stock options considered to be “plain vanilla” options, the Company estimates the expected term based on the simplified method, which is essentially the weighted average of the vesting period and contractual term, as the Company’s historical share option exercise experience does not provide a reasonable basis upon which to estimate the expected term. Expected volatility. The Company performed an analysis using the average volatility of a peer group of representative public companies with sufficient trading history over the expected term to develop an expected volatility assumption. Risk-free interest rate. Based upon quoted market yields for the United States Treasury debt securities for a term consistent with the expected life of the awards in effect at the time of grant. Expected dividend yield. Because the Company has never paid and has no intention to pay cash dividends on common stock, the expected dividend yield is zero. Fair value of underlying common stock. As of September 30, 2021, the Company’s common stock is not yet publicly traded, therefore, the Company must estimate the fair value of common stock. The Board considers numerous objective and subjective factors to determine the fair value of the Company’s common stock at each meeting in which awards are approved. The factors considered include, but are not limited to: (i) the results of contemporaneous independent third-party valuations of the Company’s common stock; (ii) the prices, rights, preferences, and privileges of the Company’s convertible preferred stock relative to those of its common stock; (iii) the lack of marketability of the Company’s common stock; (iv) actual operating and financial results; (v) current business conditions and projections; (vi) the likelihood of achieving a liquidity event, such as an initial public offering or sale of the Company, given prevailing market conditions; and (vii) precedent transactions involving the Company’s shares. Stock-based compensation expense included in the condensed statements of operations was as follows (in thousands): For the Three Months Ended September 30, For the Nine Months Ended September 30, 2021 2020 2021 2020 Cost of revenue $ 139 $ 34 $ 333 $ 57 Research and development 466 195 1,377 536 Sales and marketing 489 137 1,057 386 General and administrative 354 105 844 235 Total stock-based compensation expense $ 1,448 $ 471 $ 3,611 $ 1,214 During the nine months ended September 30, 2021 and 2020, the Company capitalized $0.3 million and $0.2 million, respectively, of stock-based compensation for the development of internal-use software. As of September 30, 2021, total compensation cost related to stock options not yet vested was approximately $20.0 million, which will be recognized over a weighted-average period of approximately 3.0 years.

Net Loss per Share Attributable

Net Loss per Share Attributable to Common Stockholders	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Net Loss per Share Attributable to Common Stockholders	Net Loss per Share Attributable to Common Stockholders Basic and diluted net loss per share attributable to common stockholders is presented in conformity with the two-class method required for participating securities. The Company considers its convertible preferred stock to be participating securities. Under the two-class method, the net loss attributable to common stockholders is not allocated to the convertible preferred stock as the holders of these participating securities do not have a contractual obligation to share in the losses of the Company. Basic net loss per share attributable to common stockholders is computed by dividing the net loss attributable to common stockholders by the weighted-average number of shares of common stock outstanding during the period. The diluted net loss per share attributable to common stockholders is computed by giving effect to all potentially dilutive common stock equivalents during the period. For purposes of this calculation, the Company’s convertible preferred stock and stock options are considered to be potential common stock equivalents, but have been excluded from the calculation of diluted net loss per share attributable to common stockholders as their effect is antidilutive. The following table presents the calculation of basic and diluted net loss per share (in thousands, except share and per share data): For the Three Months Ended September 30, For the Nine Months Ended September 30, 2021 2020 2021 2020 Numerator: Net loss attributable to common stockholders $ (5,993) $ (1,860) $ (12,099) $ (3,205) Denominator for basic and diluted net loss per share: Weighted-average shares used in computing net loss per share attributable to common stockholders – basic and diluted 18,936,698 18,614,869 18,775,908 18,607,705 Net loss per share attributable to common stockholders – basic and diluted $ (0.32) $ (0.10) $ (0.64) $ (0.17) Since the Company was in a loss position for all periods presented, basic net loss per share is the same as diluted net loss per share as the inclusion of all potential common shares outstanding would have been antidilutive. The potential shares of common stock that were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented because including them would have been antidilutive are as follows: September 30, 2021 2020 Convertible preferred stock 3,359,195 3,359,195 Stock options 13,818,295 9,931,942 Total 17,177,490 13,291,137

Income Taxes

Income Taxes	9 Months Ended
	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The Company is subject to U.S. federal and state income taxes as a corporation. The Company’s tax provision and the resulting effective tax rate for interim periods is determined based upon its estimated annual effective tax rate adjusted for the effect of discrete items arising in that quarter. The effective tax rate for the three and nine months ended September 30, 2021 and 2020 was zero as the Company has incurred continuous operating losses. The Company recorded a $0.1 million provision for income taxes during the nine months ended September 30, 2021, which includes an immaterial out of period correction of $0.2 million relating to the limitation of the net operating loss (“NOLs”) as of December 31, 2020. The charge represents the limitation on post-2017 federal NOLs which are limited to 80% beginning in years after December 31, 2020.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Since September 30, 2021, the Company has entered into various capital lease agreements for acquiring infrastructure equipment to operate its core business. The Company’s future minimum commitment under these agreements total approximately $4.9 million and extend through 2024. During October 2021, the Company entered into a revolving credit agreement with City National Bank. Under this agreement, among other things, (i) amounts available to be borrowed are $9.5 million and (ii) advances on the line of credit bear interest payable monthly at the average Secured Overnight Financing Rate (“SOFR”) rate plus 2.75%. The revolving credit agreement matures in September 2024. In connection with this agreement, the Company fully repaid and subsequently terminated its 2017 revolving credit agreement with HomeStreet Bank. On November 15, 2021, the Company had its first closing for its IPO, in which the Company issued and sold 6,250,000 shares of its Class A common stock at a public offering price of $16.00 per share. On November 17, 2021, the Company had its second closing for its initial public offering, in which the Company issued and sold 937,500 shares at the same per-share price pursuant to the exercise by the underwriters of their option to purchase such shares from the Company for the purpose of covering over-allotments. Together, these two closings resulted in net proceeds of approximately $103 million after deducting the underwriting discounts and commissions and offering expenses. In connection with the IPO and with the filing of the Company’s Amended and Restated Certificate of Incorporation in Delaware and the adoption of its Amended and Restated Bylaws, the following occurred: (i) the reclassification of all outstanding shares of the Company’s common stock into an equivalent number of shares of its Class B common stock, (ii) all shares of the convertible preferred stock then outstanding automatically converted into 3,359,195 shares of Class B common stock and (iii) all outstanding shares of the Company’s common stock converted into an equivalent number of shares of its Class B common stock and (iv) the SAFE notes automatically converted into approximately 725,000 shares of Class A common stock. Further, this new dual class structure of the Company’s common stock has the effect of concentrating voting control with those stockholders who held capital stock prior to the completion of this IPO, as Class B common stock has 10 votes per share, and Class A common stock has one vote per share. Prior to the IPO, deferred offering costs, which consist of direct incremental legal, accounting and consulting fees relating to the IPO, were capitalized. Upon the consummation of the IPO, the deferred offering costs were reclassified into stockholders’ equity as an offset against IPO proceeds. As of September 30, 2021, deferred offering costs capitalized were approximately $2.4 million, and are included in other assets on the Company’s condensed balance sheets. During December 2021, the Company issued approximately 1,450,000 stock options with service-based vesting conditions to certain employees. The service-based vesting condition for these awards is satisfied over four years with a cliff vesting period of one year and continued vesting thereafter. The Company expects to recognize approximately $14 million in stock-based compensation on a straight-line basis over the vesting period of these awards.

Basis of Presentation and Sum_2

Basis of Presentation and Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2021
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The accompanying unaudited condensed financial statements have been prepared in accordance with generally accepted accounting principles in the United States of America (“GAAP”) and applicable rules and regulations of the U.S. Securities and Exchange Commission (the “SEC”) regarding interim financial reporting. Accordingly, they do not include all disclosures normally required in annual financial statements prepared in accordance with GAAP. Therefore, these unaudited condensed financial statements should be read in conjunction with the audited financial statements and notes included in the Company’s final prospectus dated November 10, 2021 and filed with the SEC pursuant to Rule 424(b)(4) on November 12, 2021 (“Final Prospectus”). In management’s opinion, these unaudited condensed financial statements have been prepared on the same basis as the annual financial statements and 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, results of operations for the three and nine months ended September 30, 2021 and 2020, cash flows for the nine months ended September 30, 2021 and 2020, and stockholders' deficit for the three and nine months ended September 30, 2021 and 2020. The results of operations for the three and nine months ended September 30, 2021 and 2020 are not necessarily indicative of the results to be expected for the full year or any other future interim or annual period.
Segment Information	Segment Information The Company has a single operating and reportable segment. In reaching this conclusion, management considers the definition of the chief operating decision maker (“CODM”), how the business is defined by the CODM, the nature of the information provided to the CODM and how that information is used to make operating decisions, allocate resources and assess performance. The Company’s chief operating decision maker is its Chief Executive Officer, who reviews financial information presented on an aggregated basis for purposes of making operating decisions, assessing financial performance and allocating resources.
Use of Estimates	Use of Estimates The preparation of financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the amounts reported and disclosed in the financial statements and the accompanying notes. Such estimates and assumptions include the costs to be capitalized as internal-use software and their useful life, the useful lives of other long-lived assets, impairment considerations for long-lived assets, expected lease term for capital leases, calculation of the refund liability, estimates related to variable consideration, valuation of the Company’s common stock and stock options and accounting for taxes, including estimates for sales tax and VAT liability, deferred tax assets, valuation allowance and uncertain tax positions. The Company bases its estimates on historical experience and on assumptions that management considers reasonable. Future actual results could differ materially from these estimates.
Concentrations	Concentrations Credit risk. Financial instruments that potentially subject the Company to credit risk primarily consist of cash, cash equivalents and accounts receivable. The Company maintains its cash and cash equivalents with high-quality financial institutions with investment-grade ratings. Deposits with these financial institutions may exceed the amount of insurance provided on such deposits. For accounts receivable, the Company is exposed to credit risk in the event of nonpayment by customers to the extent of the amount recorded on the condensed balance sheets. Vendors. The Company acquires infrastructure equipment from third-party vendors. Vendors may have limited sources of equipment and supplies which may expose the Company to potential supply and service disruptions that could harm the Company’s business. Two vendors represented in aggregate 31% of total cash disbursements during the year ended December 31, 2020, while three vendors represented 20% of the accounts payable balance as of December 31, 2020. Two vendors represented an aggregate 25% of total cash disbursements during the nine months ended September 30, 2021, while three vendors represented an aggregate 45% of the accounts payable balance as of September 30, 2021. Revenue. The Company derives substantially all of its revenue from the services operating on its Backblaze Storage Cloud platform: its Backblaze B2 Cloud Storage (“Backblaze B2”) and Backblaze Computer Backup (“Computer Backup”) offerings. The potential for severe impact to the Company’s business could result if the Company was unable to operate its platform or serve customers through its platform for an extended period of time.
Accounting Pronouncements Not Yet Adopted	Accounting Pronouncements Not Yet Adopted In February 2016, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2016-02, Leases (Topic 842 ), which requires the recognition of lease assets and lease liabilities arising from operating leases on the balance sheet. Subsequently, the FASB also issued a series of amendments to this new lease standard that address the transition methods available and clarify the guidance for lessor costs and other aspects of the new lease standard. The Company will adopt the standard effective January 1, 2022 and expects to adopt using the modified retrospective transition method without restating comparative periods. The Company is currently evaluating the impact of the adoption of this guidance on its financial statements. In June 2016, the FASB issued ASU 2016-13, Financial Instruments—Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments, which requires a financial asset measured at amortized cost basis to be presented at the net amount expected to be collected, with further clarifications made more recently. For trade receivables, loans and other financial instruments, the Company will be required to use a forward-looking expected loss model rather than the incurred loss model for recognizing credit losses which reflects losses that are probable. Credit losses relating to available-for-sale debt securities are required to be recorded through an allowance for credit losses rather than as a reduction in the amortized cost basis of the securities. This guidance is effective for the Company for its fiscal year beginning January 1, 2023 and interim periods within that fiscal year. The Company is currently evaluating the impact of the adoption of this guidance on its financial statements. In August 2018, the FASB issued ASU No. 2018-15, Intangibles—Goodwill and Other—Internal-Use Software (Subtopic 350-40), which aligns the requirements for capitalizing implementation costs incurred in a hosting arrangement that is a service contract with the requirements for capitalizing implementation costs incurred to develop or obtain internal-use software (and hosting arrangements that include an internal-use software license). The accounting for the service element of a hosting arrangement that is a service contract is not affected by this new guidance. This new guidance is effective for the Company for its fiscal year beginning January 1, 2021 and interim periods within its fiscal year beginning January 1, 2022. Early adoption is permitted. The Company plans to adopt this guidance prospectively and does not expect the adoption of this guidance will have a material impact on its financial statements for the fiscal year ended December 31, 2021. In December 2019, the FASB issued ASU 2019-12, Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes, which simplifies the accounting for income taxes by eliminating some exceptions to the general approach in ASC 740, Income Taxes, in order to reduce cost and complexity of its application. This new guidance is effective for the Company for its fiscal year beginning January 1, 2022 and interim periods within its fiscal year beginning January 1, 2023. Early adoption is permitted. The Company is currently evaluating the impact of the adoption of this guidance on its financial statements.

Revenues (Tables)

Revenues (Tables)	9 Months Ended
	Sep. 30, 2021
Revenue from Contract with Customer [Abstract]
Disaggregation of Revenue	The following table presents the Company’s revenues disaggregated by timing of revenue recognition (in thousands): For the Three Months Ended September 30, For the Nine Months Ended September 30, 2021 2020 2021 2020 Consumption-based arrangements (B2 Cloud Storage) $ 5,977 $ 3,757 $ 16,026 $ 10,018 Subscription-based arrangements (Computer Backup) 11,163 9,894 32,219 28,696 Physical Media 180 166 537 482 Total revenue $ 17,320 $ 13,817 $ 48,782 $ 39,196
Revenue by Geographic Area	Revenue by geographic area, based on the location of the Company’s customers, was as follows (in thousands): For the Three Months Ended September 30, For the Nine Months Ended September 30, 2021 2020 2021 2020 United States $ 12,435 $ 9,960 $ 35,083 $ 28,469 Other 4,885 3,857 13,699 10,727 Total $ 17,320 $ 13,817 $ 48,782 $ 39,196

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2021
Fair Value Disclosures [Abstract]
Schedule of Fair Value Hierarchy of Assets and Liabilities Measured on a Recurring Basis	The following table presents the fair value hierarchy for the Company’s assets and liabilities measured at fair value on a recurring basis as of September 30, 2021 and as of December 31, 2020 (in thousands): Level 1 Level 2 Level 3 September 30, December 31, September 30, December 31, September 30, December 31, Assets Cash equivalents: Money market funds $ 44 $ 2,651 $ — $ — $ — $ — Total $ 44 $ 2,651 $ — $ — $ — $ — Liabilities SAFE notes $ — $ — $ — $ — $ 10,359 $ — Total $ — $ — $ — $ — $ 10,359 $ —
Schedule of Fair Value Instruments Classified as Level 3	The following table summarizes the total carrying value of the Company’s Level 3 instruments held as of September 30, 2021 including cumulative unrealized gains and losses recognized during the nine months ended September 30, 2021 (in thousands): Nine Months Ended September 30, 2021 Beginning balance as of December 31, 2020 $ — Sale of SAFE notes 10,000 Total unrealized loss 359 Ending balance as of September 30, 2021 $ 10,359

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	9 Months Ended
	Sep. 30, 2021
Prepaid Expense and Other Assets, Current [Abstract]
Schedule of Other Current Assets	Prepaid expenses and other current assets consisted of the following (in thousands): September 30, December 31, Unbilled accounts receivable $ 1,150 $ 841 Prepaid expenses 633 643 Prepaid subscriptions 547 276 Capitalized commissions 343 315 Receivable from payment processor 468 268 Prepaid flash drives 347 — Prepaid data migration fees 103 71 Deposits 179 19 Other 234 514 Total prepaid expenses and other current assets $ 4,004 $ 2,947

Property and Equipment, Net (Ta

Property and Equipment, Net (Tables)	9 Months Ended
	Sep. 30, 2021
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment	Property and equipment, net consisted of the following (in thousands): September 30, December 31, Data center equipment $ 11,053 $ 10,538 Leased data center equipment 58,826 51,852 Machinery and equipment 7,055 4,369 Computer equipment 1,496 1,176 Leasehold improvements 900 876 Construction-in-process 167 2,358 Total property and equipment 79,497 71,169 Less: accumulated depreciation (39,102) (32,423) Total property and equipment, net $ 40,395 $ 38,746

Capitalized_Internal-use_Soft_2

Capitalized Internal-use Software, Net (Tables)	9 Months Ended
	Sep. 30, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Finite-Lived Intangible Assets	Capitalized internal-use software, net consisted of the following (in thousands): September 30, December 31, Developed software $ 11,476 $ 8,593 Software purchased for internal-use 870 466 Total capitalized internal-use software 12,346 9,059 Less: accumulated amortization (4,627) (3,377) Total capitalized internal-use software, net $ 7,719 $ 5,682
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	As of September 30, 2021, future amortization expense is expected to be as follows (in thousands): Year Ending December 31, Remainder of 2021 $ 500 2022 1,998 2023 1,833 2024 1,569 2025 1,102 Thereafter 717 Total $ 7,719

Accrued Expenses and Other Cu_2

Accrued Expenses and Other Current Liabilities (Tables)	9 Months Ended
	Sep. 30, 2021
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued expenses and other current liabilities consisted of the following (in thousands): September 30, December 31, Accrued compensation $ 1,125 $ 1,295 Accrued expenses 1,488 1,284 Accrued sales tax 977 598 Accrued income tax 141 5 Other 358 414 Accrued expenses and other current liabilities $ 4,089 $ 3,596

Commitment and Contingencies (T

Commitment and Contingencies (Tables)	9 Months Ended
	Sep. 30, 2021
Commitments and Contingencies Disclosure [Abstract]
Schedule of Future Minimum Lease Payments for Capital Leases	As of September 30, 2021, the future minimum payments related to the lease agreements consisted of the following (in thousands): Year Ending December 31, Remainder of 2021 $ 212 2022 848 2023 848 2024 840 2025 387 Thereafter — Total $ 3,135

Stockholders' Deficit (Tables)

Stockholders' Deficit (Tables)	9 Months Ended
	Sep. 30, 2021
Equity [Abstract]
Schedule of Shares Reserved for Future Issuance	The Company had reserved shares of common stock for future issuance as follows: September 30, December 31, Convertible preferred stock 3,359,195 3,359,195 2011 Equity Incentive Plan Options outstanding 13,818,295 11,409,736 Shares available for future grants 114,987 865,339 Total 17,292,477 15,634,270
Summary of Stock Option Activity	A summary of stock option activity under the Plan and related information is as follows (in thousands, except share, price and year data): Shares Outstanding Weighted- Weighted- Aggregate Balance as of December 31, 2020 865,339 11,409,736 $ 2.27 6.52 $ 36,889 Shares authorized 1,980,000 Granted (2,994,120) 2,994,120 7.16 Exercised — (321,793) 0.61 Cancelled 263,768 (263,768) 3.54 Balance as of September 30, 2021 114,987 13,818,295 $ 3.35 6.69 $ 169,042 Vested and exercisable as of September 30, 2021 8,110,364 $ 2.05 4.97 $ 109,769

Stock-Based Compensation (Table

Stock-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2021
Share-based Payment Arrangement [Abstract]
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The following table summarizes the Black-Scholes option pricing model weighted-average assumptions used in estimating the fair value of stock options granted to employees during the three months ended September 30, 2021, and during the nine months ended September 30, 2021 and 2020. No options grants were made during the three months ended September 30, 2020. Three Months Ended September 30, Nine Months Ended September 30, 2021 2020 2021 2020 Expected term (in years) 6.0 — 6.0 6.0 Expected volatility 48.8 % — % 49.1 % 48.5 % Risk-free interest rate 0.93 % — % 1.05 % 0.41 %
Classification of Stock-Based Compensation	Stock-based compensation expense included in the condensed statements of operations was as follows (in thousands): For the Three Months Ended September 30, For the Nine Months Ended September 30, 2021 2020 2021 2020 Cost of revenue $ 139 $ 34 $ 333 $ 57 Research and development 466 195 1,377 536 Sales and marketing 489 137 1,057 386 General and administrative 354 105 844 235 Total stock-based compensation expense $ 1,448 $ 471 $ 3,611 $ 1,214

Net Loss per Share Attributab_2

Net Loss per Share Attributable to Common Stockholders (Tables)	9 Months Ended
	Sep. 30, 2021
Earnings Per Share [Abstract]
Schedule of Earnings Per Share Basic and Diluted	The following table presents the calculation of basic and diluted net loss per share (in thousands, except share and per share data): For the Three Months Ended September 30, For the Nine Months Ended September 30, 2021 2020 2021 2020 Numerator: Net loss attributable to common stockholders $ (5,993) $ (1,860) $ (12,099) $ (3,205) Denominator for basic and diluted net loss per share: Weighted-average shares used in computing net loss per share attributable to common stockholders – basic and diluted 18,936,698 18,614,869 18,775,908 18,607,705 Net loss per share attributable to common stockholders – basic and diluted $ (0.32) $ (0.10) $ (0.64) $ (0.17)
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	The potential shares of common stock that were excluded from the computation of diluted net loss per share attributable to common stockholders for the periods presented because including them would have been antidilutive are as follows: September 30, 2021 2020 Convertible preferred stock 3,359,195 3,359,195 Stock options 13,818,295 9,931,942 Total 17,177,490 13,291,137

Basis of Presentation and Sum_3

Basis of Presentation and Summary of Significant Accounting Policies (Details)	1 Months Ended	9 Months Ended	12 Months Ended
	Oct. 31, 2021	Sep. 30, 2021segment	Dec. 31, 2020
Concentration Risk [Line Items]
Number of operating segments		1
Number of reporting units		1
Supplier Concentration Risk | Cash Disbursements | Two Vendors
Concentration Risk [Line Items]
Concentration risk, percentage		25.00%	31.00%
Supplier Concentration Risk | Accounts Payable | Three Vendors
Concentration Risk [Line Items]
Concentration risk, percentage		45.00%	20.00%
Subsequent Event
Concentration Risk [Line Items]
Stock split ratio	3.6

Revenues - Narrative (Details)

Revenues - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Amortization of deferred contract costs	$ 200	$ 200	$ 579	$ 489
Capitalized contract cost	400		400		$ 400
Contract with Customer, Liability	24,500		24,500		$ 19,400
Contract with customer, liability, revenue recognized	$ 7,600	$ 6,800	$ 15,600	$ 13,800

Revenues - Disaggregation of Re

Revenues - Disaggregation of Revenues (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	$ 17,320	$ 13,817	$ 48,782	$ 39,196
United States
Disaggregation of Revenue [Line Items]
Revenue	12,435	9,960	35,083	28,469
Other
Disaggregation of Revenue [Line Items]
Revenue	4,885	3,857	13,699	10,727
Consumption-based arrangements (B2 Cloud Storage)
Disaggregation of Revenue [Line Items]
Revenue	5,977	3,757	16,026	10,018
Subscription-based arrangements (Computer Backup)
Disaggregation of Revenue [Line Items]
Revenue	11,163	9,894	32,219	28,696
Physical Media
Disaggregation of Revenue [Line Items]
Revenue	$ 180	$ 166	$ 537	$ 482

Cash Equivalents (Details)

Cash Equivalents (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Cash and Cash Equivalents [Line Items]
Cash equivalents	$ 4,684	$ 6,076
Money market funds
Cash and Cash Equivalents [Line Items]
Cash equivalents	$ 100	$ 2,700

Fair Value Measurements - Asset

Fair Value Measurements - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Level 1
Assets
Total	$ 44	$ 2,651
Liabilities
Total	0	0
Level 1 | Long-term Debt
Liabilities
SAFE notes	0	0
Level 1 | Money market funds
Assets
Money market funds	44	2,651
Level 2
Assets
Total	0	0
Liabilities
Total	0	0
Level 2 | Long-term Debt
Liabilities
SAFE notes	0	0
Level 2 | Money market funds
Assets
Money market funds	0	0
Level 3
Assets
Total	0	0
Liabilities
Total	10,359	0
Level 3 | Long-term Debt
Liabilities
SAFE notes	10,359	0
Level 3 | Money market funds
Assets
Money market funds	$ 0	$ 0

Fair Value Measurements - Narra

Fair Value Measurements - Narrative (Details) - Fair Value, Recurring - Level 3	Sep. 30, 2021
Measurement Input, Discount Rate
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Long-term debt, measurement input	0.30
Minimum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Long-term debt, measurement input	0.05
Maximum
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Long-term debt, measurement input	0.65

Fair Value Measurements - Fair

Fair Value Measurements - Fair Value of Instruments Classified as Level 3 (Details) - Fair Value, Recurring - Level 3 $ in Thousands	9 Months Ended
	Sep. 30, 2021USD ($)
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Beginning balance as of December 31, 2020	$ 0
Ending balance as of September 30, 2021	10,359
Long-term Debt
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Sale of SAFE notes	10,000
Total unrealized loss	$ 359

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Prepaid Expense and Other Assets, Current [Abstract]
Unbilled accounts receivable	$ 1,150	$ 841
Prepaid expenses	633	643
Prepaid subscriptions	547	276
Capitalized commissions	343	315
Receivable from payment processor	468	268
Prepaid flash drives	347	0
Prepaid data migration fees	103	71
Deposits	179	19
Other	234	514
Total prepaid expenses and other current assets	$ 4,004	$ 2,947

Property and Equipment, Net (De

Property and Equipment, Net (Details) - USD ($) $ in Thousands	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]
Total property and equipment	$ 79,497		$ 79,497		$ 71,169
Less: accumulated depreciation	(39,102)		(39,102)		(32,423)
Total property and equipment, net	40,395		40,395		38,746
Depreciation	3,600	$ 3,000	10,800	$ 8,200
Data center equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	11,053		11,053		10,538
Leased data center equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	58,826		58,826		51,852
Machinery and equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	7,055		7,055		4,369
Computer equipment
Property, Plant and Equipment [Line Items]
Total property and equipment	1,496		1,496		1,176
Leasehold improvements
Property, Plant and Equipment [Line Items]
Total property and equipment	900		900		876
Construction-in-process
Property, Plant and Equipment [Line Items]
Total property and equipment	$ 167		$ 167		$ 2,358

Capitalized_Internal-use_Soft_3

Capitalized Internal-use Software, Net - Capitalized Internal Use Software (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Finite-Lived Intangible Assets [Line Items]
Total capitalized internal-use software	$ 12,346	$ 9,059
Less: accumulated amortization	(4,627)	(3,377)
Total capitalized internal-use software, net	7,719	5,682
Developed software
Finite-Lived Intangible Assets [Line Items]
Total capitalized internal-use software	11,476	8,593
Software purchased for internal-use
Finite-Lived Intangible Assets [Line Items]
Total capitalized internal-use software	$ 870	$ 466

Capitalized_Internal-use_Soft_4

Capitalized Internal-use Software, Net - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Goodwill and Intangible Assets Disclosure [Abstract]
Capitalized computer software, amortization	$ 0.4	$ 0.3	$ 1.2	$ 0.9

Capitalized_Internal-use_Soft_5

Capitalized Internal-use Software, Net (Details) - Capitalized Computer Software $ in Thousands	Sep. 30, 2021USD ($)
Finite-Lived Intangible Assets [Line Items]
Remainder of 2021	$ 500
2022	1,998
2023	1,833
2024	1,569
2025	1,102
Thereafter	717
Total	$ 7,719

Accrued Expenses and Other Cu_3

Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Payables and Accruals [Abstract]
Accrued compensation	$ 1,125	$ 1,295
Accrued expenses	1,488	1,284
Accrued sales tax	977	598
Accrued income tax	141	5
Other	358	414
Accrued expenses and other current liabilities	$ 4,089	$ 3,596

Commitment and Contingencies -

Commitment and Contingencies - Narrative (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021USD ($)	Sep. 30, 2020USD ($)	Sep. 30, 2021USD ($)arrangement	Sep. 30, 2020USD ($)	Dec. 31, 2020USD ($)
Other Commitments [Line Items]
Capital leases, depreciation expense	$ 3,000	$ 2,100	$ 8,900	$ 6,400
Sale leaseback transactions, number of arrangements | arrangement			2
Proceeds from sale leaseback transaction			$ 2,900
Operating leases, rent expense	1,900	1,500	5,100	3,900
Purchase obligation, to be paid, remainder of fiscal year	600		600
Purchase obligation, to be paid, year one	300		300
Plan contributions	300	$ 200	800	$ 500
Accrual for sales tax payable	1,000		1,000		$ 600
Accrued VAT liability	$ 2,275		$ 2,275		$ 1,533
Minimum
Other Commitments [Line Items]
Capital leases, agreement term			3 years
Maximum
Other Commitments [Line Items]
Capital leases, agreement term			4 years

Commitment and Contingencies _2

Commitment and Contingencies - Future Minimum Payments (Details) $ in Thousands	Sep. 30, 2021USD ($)
Commitments and Contingencies Disclosure [Abstract]
Remainder of 2021	$ 212
2022	848
2023	848
2024	840
2025	387
Thereafter	0
Total	$ 3,135

Debt (Details)

Debt (Details) - USD ($)	Apr. 22, 2020	Oct. 11, 2017	Jun. 30, 2021	Apr. 30, 2021	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Aug. 31, 2021
Debt Instrument [Line Items]
Proceeds from PPP							$ 0	$ 2,272,000
Gain on extinguishment of debt					$ 0	$ 0	2,299,000	0
Unrealized loss on SAFE					359,000	$ 0	359,000	$ 0
Paycheck Protection Program, CARES Act
Debt Instrument [Line Items]
Proceeds from PPP	$ 2,300,000
Interest rate, stated percentage	0.01%
Gain on extinguishment of debt			$ 2,300,000
Line of Credit | Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 15,000,000		$ 10,000,000
Line of Credit | Revolving Credit Facility | Prime Rate
Debt Instrument [Line Items]
Basis spread on variable rate		0.25%		1.00%
Convertible Debt | SAFE Notes
Debt Instrument [Line Items]
Interest rate, stated percentage									5.00%
Debt instrument, face amount									$ 10,000,000
Debt instrument, convertible, discount percent									10.00%
Debt instrument, convertible, discount percent, annual increase									10.00%
Debt instrument, convertible, maximum discount percent									50.00%
Unrealized loss on SAFE							400,000
Convertible Debt | SAFE Notes | TMT Investments PLC
Debt Instrument [Line Items]
Long-term debt					$ 2,000,000		$ 2,000,000

Stockholders' Deficit - Common

Stockholders' Deficit - Common Stock Reserved for Future Issuance (Details) - shares	Sep. 30, 2021	Dec. 31, 2020
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	17,292,477	15,634,270
2011 Equity Incentive Plan
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	114,987	865,339
2011 Equity Incentive Plan | Options outstanding
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	13,818,295	11,409,736
Convertible preferred stock
Class of Stock [Line Items]
Common stock reserved for future issuance (in shares)	3,359,195	3,359,195

Stockholders' Deficit - Narrati

Stockholders' Deficit - Narrative (Details) $ / shares in Units, $ in Thousands	1 Months Ended					9 Months Ended
	Aug. 31, 2021shares	Jun. 30, 2021USD ($)employeeshares	Mar. 31, 2021shares	Apr. 30, 2020shares	May 31, 2019shares	Sep. 30, 2021USD ($)$ / sharesshares	Sep. 30, 2020USD ($)$ / shares	Dec. 31, 2020shares	Dec. 31, 2019shares
Class of Stock [Line Items]
Shares authorized (in shares)								1,980,000
Weighted-average grant-date fair value of options granted (USD per share) | $ / shares						$ 5.39	$ 1.84
Intrinsic value of options exercised | $						$ 4,800	$ 100
Aggregate grant-date fair value of options vested | $						$ 2,500	$ 1,100
Issuance of common stock upon exercise of stock options (in shares)		234,526				321,793
Employees
Class of Stock [Line Items]
Notes receivable, number of employees | employee		4
Notes receivable, related parties | $		$ 48
Interest rate, percentage		0.13%
The Plan
Class of Stock [Line Items]
Number of additional shares authorized (in shares)	180,000		1,800,000	2,700,000	1,800,000
Shares authorized (in shares)			14,220,000			14,400,000		12,420,000	9,720,000
The Plan | Options outstanding
Class of Stock [Line Items]
Award vesting period						4 years
Award expiration period						10 years

Stockholders' Deficit - Summary

Stockholders' Deficit - Summary of Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
	Jun. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Dec. 31, 2020
Shares available for grant
Balance as of beginning of period (in shares)			865,339
Shares authorized (in shares)				1,980,000
Granted (in shares)			(2,994,120)
Exercised (in shares)			0
Cancelled (in shares)			263,768
Balance as of end of period (in shares)			114,987	865,339
Outstanding Stock Options
Balance as of beginning of period (in shares)			11,409,736
Granted (in shares)		0	2,994,120
Exercised (in shares)	(234,526)		(321,793)
Cancelled (in shares)			(263,768)
Balance as of end of period (in shares)			13,818,295	11,409,736
Vested and exercisable, end of period (in shares)			8,110,364
Weighted-average exercise Price
Balance as of beginning of period (USD per share)			$ 2.27
Granted (USD per share)			7.16
Exercised (USD per share)			0.61
Cancelled (USD per share)			3.54
Balance as of end of period (USD per share)			3.35	$ 2.27
Vested and exercisable, end of period (USD per share)			$ 2.05
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Options outstanding, Weighted-average remaining contractual life (years)			6 years 8 months 8 days	6 years 6 months 7 days
Vested and exercisable, Weighted-average remaining contractual life, end of period (years)			4 years 11 months 19 days
Options outstanding, Aggregate intrinsic value			$ 169,042	$ 36,889
Vested and exercisable, Aggregate intrinsic value, end of period			$ 109,769

Stock-Based Compensation - Narr

Stock-Based Compensation - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement [Abstract]
Grants in period (in shares)	0	2,994,120
Stock-based compensation capitalized internal-use software		$ 271	$ 159
Cost not yet recognized, amount		$ 20,000
Cost not yet recognized, period for recognition		3 years

Share-Based Payments - Valuatio

Share-Based Payments - Valuation Assumptions for Stock Options (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement [Abstract]
Expected term (in years)	6 years	0 years	6 years	6 years
Volatility (in percent)	48.80%	0.00%	49.10%	48.50%
Risk free interest rate (in percent)	0.93%	0.00%	1.05%	0.41%
Dividend yield			0.00%

Stock-Based Compensation - Clas

Stock-Based Compensation - Classification of Stock-Based Compensation (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 1,448	$ 471	$ 3,611	$ 1,214
Cost of Sales
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	139	34	333	57
Research and Development Expense
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	466	195	1,377	536
Sales and marketing
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	489	137	1,057	386
General and administrative
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Stock-based compensation expense	$ 354	$ 105	$ 844	$ 235

Net Loss per Share Attributab_3

Net Loss per Share Attributable to Common Stockholders (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Numerator:
Net loss	$ (5,993)	$ (1,860)	$ (12,099)	$ (3,205)
Denominator for basic and diluted net loss per share:
Weighted average shares used in computing net loss per share, basic (in shares)	18,936,698	18,614,869	18,775,908	18,607,705
Weighted average shares used in computing net loss per share, diluted (in shares)	18,936,698	18,614,869	18,775,908	18,607,705
Net loss per share, basic (USD per share)	$ (0.32)	$ (0.10)	$ (0.64)	$ (0.17)
Net loss per share, diluted (USD per share)	$ (0.32)	$ (0.10)	$ (0.64)	$ (0.17)

Net Loss per Share Attributab_4

Net Loss per Share Attributable to Common Stockholders - Antidilutive Securities (Details) - shares	9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Common Share [Line Items]
Antidilutive securities (in shares)	17,177,490	13,291,137
Convertible preferred stock
Earnings Per Common Share [Line Items]
Antidilutive securities (in shares)	3,359,195	3,359,195
Options outstanding
Earnings Per Common Share [Line Items]
Antidilutive securities (in shares)	13,818,295	9,931,942

Income Taxes (Details)

Income Taxes (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Effective income tax rate	0.00%	0.00%	0.00%	0.00%
Income tax expense	$ 0	$ 12	$ 136	$ 12
Tax adjustment			$ 200

Subsequent Events (Details)

Subsequent Events (Details)	Dec. 14, 2021USD ($)shares	Nov. 17, 2021USD ($)	Nov. 17, 2021shares	Nov. 15, 2021vote$ / sharesshares	Oct. 31, 2021USD ($)	Sep. 30, 2020shares	Sep. 30, 2021USD ($)shares	Apr. 30, 2021USD ($)	Oct. 11, 2017USD ($)
Subsequent Event [Line Items]
Future minimum commitments							$ 3,135,000
Deferred offering costs, net, included in equity							$ 2,400,000
Grants in period (in shares) | shares						0	2,994,120
Cost not yet recognized, amount							$ 20,000,000
Revolving Credit Facility | Line of Credit
Subsequent Event [Line Items]
Maximum borrowing capacity								$ 10,000,000	$ 15,000,000
Subsequent Event
Subsequent Event [Line Items]
Future minimum commitments	$ 4,900,000
Net proceeds		$ 103,000,000
Grants in period (in shares) | shares	1,450,000
Subsequent Event | Options outstanding
Subsequent Event [Line Items]
Award vesting period	4 years
Cost not yet recognized, amount	$ 14,000,000
Subsequent Event | Options outstanding | Cliff vesting
Subsequent Event [Line Items]
Award vesting period	1 year
Subsequent Event | Common Class B
Subsequent Event [Line Items]
Conversion of convertible preferred stock (in shares) | shares				3,359,195
Common stock, votes per share | vote				10
Subsequent Event | Common Class A
Subsequent Event [Line Items]
Conversion of convertible debt (in shares) | shares				725,000
Common stock, votes per share | vote				1
Subsequent Event | IPO
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares) | shares				6,250,000
Price per share (in dollars per share) | $ / shares				$ 16
Subsequent Event | Over-Allotment Option
Subsequent Event [Line Items]
Number of shares issued in transaction (in shares) | shares			937,500
Subsequent Event | Revolving Credit Facility | Line of Credit
Subsequent Event [Line Items]
Maximum borrowing capacity					$ 9,500,000
Subsequent Event | Revolving Credit Facility | Line of Credit | Secured Overnight Financing Rate (SOFR)
Subsequent Event [Line Items]
Basis spread on variable rate					2.75%