Willdan (WLDN) 10-Q 5 Nov 21 2021 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Oct. 01, 2021	Nov. 03, 2021
Document and Entity Information
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Oct. 1, 2021
Entity File Number	001-33076
Entity Registrant Name	WILLDAN GROUP, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	14-1951112
Entity Address, Address Line One	2401 East Katella Avenue
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Anaheim
Entity Address, Postal Zip Code	92806
Entity Address, State or Province	CA
City Area Code	800
Local Phone Number	424-9144
Title of 12(b) Security	Common Stock, par value $0.01 per share
Trading Symbol	WLDN
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		12,791,789
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	Q3
Document Fiscal Year Focus	2021
Entity Central Index Key	0001370450
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Oct. 01, 2021	Jan. 01, 2021
Current assets:
Cash and cash equivalents	$ 4,805	$ 28,405
Accounts receivable, net of allowance for doubtful accounts of $1,723 and $2,127 at October 1, 2021 and January 1, 2021, respectively	62,208	60,403
Contract assets	65,744	62,426
Other receivables	6,029	6,405
Prepaid expenses and other current assets	3,736	5,564
Total current assets	142,522	163,203
Equipment and leasehold improvements, net	14,360	12,506
Goodwill	130,124	130,124
Right-of-use assets	16,096	20,130
Other intangible assets, net	55,599	64,256
Other assets	10,550	5,993
Deferred income taxes, net	17,655	14,111
Total assets	386,906	410,323
Current liabilities:
Accounts payable	23,585	41,372
Accrued liabilities	47,185	41,754
Contingent consideration payable	8,846	12,321
Contract liabilities	8,450	7,434
Notes payable	13,336	14,996
Finance lease obligations	372	248
Lease liability	5,472	5,844
Total current liabilities	107,246	123,969
Contingent consideration payable	719	2,999
Notes payable	88,746	98,178
Finance lease obligations, less current portion	659	236
Lease liability, less current portion	11,842	15,649
Other noncurrent liabilities	80	128
Total liabilities	209,292	241,159
Commitments and contingencies
Stockholders' equity:
Preferred stock, $0.01 par value, 10,000 shares authorized, no shares issued and outstanding
Common stock, $0.01 par value, 40,000 shares authorized; 12,789 and 12,160 shares issued and outstanding at October 1, 2021 and January 1, 2021, respectively	128	122
Additional paid-in capital	164,642	149,014
Accumulated other comprehensive loss	(145)	(488)
Retained earnings	12,989	20,516
Total stockholders' equity	177,614	169,164
Total liabilities and stockholders' equity	$ 386,906	$ 410,323

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Oct. 01, 2021	Jan. 01, 2021
CONDENSED CONSOLIDATED BALANCE SHEETS
Accounts receivable, allowance for doubtful accounts (in dollars)	$ 1,723	$ 2,127
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized	10,000	10,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized	40,000	40,000
Common stock, shares issued	12,789	12,160
Common stock, shares outstanding	12,789	12,160

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Contract revenue	$ 98,297	$ 104,508	$ 261,537	$ 294,083
Direct costs of contract revenue (inclusive of directly related depreciation and amortization):
Salaries and wages	16,346	16,332	48,532	48,897
Subcontractor services and other direct costs	43,824	53,520	111,860	150,295
Total direct costs of contract revenue	60,170	69,852	160,392	199,192
General and administrative expenses:
Salaries and wages, payroll taxes and employee benefits	19,374	17,530	57,530	53,273
Facilities and facility related	2,351	2,661	7,373	7,997
Stock-based compensation	4,210	3,978	14,349	12,803
Depreciation and amortization	4,267	4,339	12,678	14,324
Other	6,482	4,547	19,033	17,003
Total general and administrative expenses	36,684	33,055	110,963	105,400
Income (Loss) from operations	1,443	1,601	(9,818)	(10,509)
Other income (expense):
Interest expense, net	(937)	(1,213)	(3,100)	(3,983)
Other, net	98	666	34	712
Total other expense, net	(839)	(547)	(3,066)	(3,271)
Income (Loss) before income taxes	604	1,054	(12,884)	(13,780)
Income tax (benefit) expense	(236)	(1,586)	(5,357)	(3,281)
Net income (loss)	840	2,640	(7,527)	(10,499)
Other comprehensive income (loss):
Unrealized gain (loss) on derivative contracts, net of tax	111	160	343	(206)
Comprehensive income (loss)	$ 951	$ 2,800	$ (7,184)	$ (10,705)
Earnings (Loss) per share:
Basic	$ 0.07	$ 0.22	$ (0.61)	$ (0.90)
Diluted	$ 0.06	$ 0.21	$ (0.61)	$ (0.90)
Weighted-average shares outstanding:
Basic	12,606	11,992	12,391	11,723
Diluted	13,141	12,417	12,391	11,723

CONDENSED CONSOLIDATED STATEM_2

CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Common Stock	Additional Paid-in Capital	Accumulated Other Comprehensive Income (Loss)	Retained Earnings	Total
Balances at Dec. 27, 2019	$ 115	$ 132,547	$ (396)	$ 35,012	$ 167,278
Balances (in shares) at Dec. 27, 2019	11,497
Increase (Decrease) in Stockholders' Equity
Shares of common stock issued in connection with employee stock purchase plan		1,073			1,073
Shares of common stock issued in connection with employee stock purchase plan (in shares)	40
Shares of common stock issued in connection with incentive stock plan		260			260
Shares of common stock issued in connection with incentive stock plan (in shares)	19
Shares used to pay taxes on stock grants	$ (1)	(2,866)			(2,867)
Shares used to pay taxes on stock grants (in shares)	(92)
Issuance of restricted stock award and units	$ 2	(1)			1
Issuance of restricted stock award and units (in shares)	176
Stock-based compensation expense		4,595			4,595
Net income (loss)				(8,154)	(8,154)
Net unrealized gain (loss) on derivative contracts			(449)		(449)
Balances at Apr. 03, 2020	$ 116	135,608	(845)	26,858	161,737
Balances (in shares) at Apr. 03, 2020	11,640
Balances at Dec. 27, 2019	$ 115	132,547	(396)	35,012	167,278
Balances (in shares) at Dec. 27, 2019	11,497
Increase (Decrease) in Stockholders' Equity
Net income (loss)					(10,499)
Net unrealized gain (loss) on derivative contracts					(206)
Balances at Oct. 02, 2020	$ 121	145,344	(602)	24,513	169,376
Balances (in shares) at Oct. 02, 2020	12,074
Balances at Apr. 03, 2020	$ 116	135,608	(845)	26,858	161,737
Balances (in shares) at Apr. 03, 2020	11,640
Increase (Decrease) in Stockholders' Equity
Shares of common stock issued in connection with incentive stock plan	$ 1	330			331
Shares of common stock issued in connection with incentive stock plan (in shares)	63
Issuance of restricted stock award and units	$ 3	(3)
Issuance of restricted stock award and units (in shares)	309
Stock-based compensation expense		4,230			4,230
Net income (loss)				(4,985)	(4,985)
Net unrealized gain (loss) on derivative contracts			83		83
Balances at Jul. 03, 2020	$ 120	140,165	(762)	21,873	161,396
Balances (in shares) at Jul. 03, 2020	12,012
Increase (Decrease) in Stockholders' Equity
Shares of common stock issued in connection with employee stock purchase plan	$ 1	1,151			1,151
Shares of common stock issued in connection with employee stock purchase plan (in shares)	54
Shares of common stock issued in connection with incentive stock plan	$ 0	61			62
Shares of common stock issued in connection with incentive stock plan (in shares)	9
Shares used to pay taxes on stock grants	$ 0	(11)			(11)
Shares used to pay taxes on stock grants (in shares)	0
Stock-based compensation expense		3,978			3,978
Net income (loss)				2,640	2,640
Net unrealized gain (loss) on derivative contracts			160		160
Balances at Oct. 02, 2020	$ 121	145,344	(602)	24,513	169,376
Balances (in shares) at Oct. 02, 2020	12,074
Balances at Jan. 01, 2021	$ 122	149,014	(488)	20,516	$ 169,164
Balances (in shares) at Jan. 01, 2021	12,160				12,160
Increase (Decrease) in Stockholders' Equity
Shares of common stock issued in connection with employee stock purchase plan	$ 1	1,384			$ 1,385
Shares of common stock issued in connection with employee stock purchase plan (in shares)	66
Shares of common stock issued in connection with incentive stock plan		527			527
Shares of common stock issued in connection with incentive stock plan (in shares)	27
Shares used to pay taxes on stock grants		(12)			(12)
Issuance of restricted stock award and units	$ 2	(3)			(1)
Issuance of restricted stock award and units (in shares)	255
Stock-based compensation expense		4,206			4,206
Net income (loss)				(3,766)	(3,766)
Net unrealized gain (loss) on derivative contracts			128		128
Balances at Apr. 02, 2021	$ 125	155,116	(360)	16,750	171,631
Balances (in shares) at Apr. 02, 2021	12,508
Balances at Jan. 01, 2021	$ 122	149,014	(488)	20,516	$ 169,164
Balances (in shares) at Jan. 01, 2021	12,160				12,160
Increase (Decrease) in Stockholders' Equity
Net income (loss)					$ (7,527)
Net unrealized gain (loss) on derivative contracts					343
Balances at Oct. 01, 2021	$ 128	164,642	(145)	12,989	$ 177,614
Balances (in shares) at Oct. 01, 2021	12,789				12,789
Balances at Apr. 02, 2021	$ 125	155,116	(360)	16,750	$ 171,631
Balances (in shares) at Apr. 02, 2021	12,508
Increase (Decrease) in Stockholders' Equity
Shares of common stock issued in connection with incentive stock plan	$ 1	850			851
Shares of common stock issued in connection with incentive stock plan (in shares)	77
Shares used to pay taxes on stock grants	$ (1)	(3,104)			(3,105)
Shares used to pay taxes on stock grants (in shares)	(79)
Issuance of restricted stock award and units	$ 2	(2)
Issuance of restricted stock award and units (in shares)	207
Stock-based compensation expense		5,933			5,933
Net income (loss)				(4,601)	(4,601)
Net unrealized gain (loss) on derivative contracts			104		104
Balances at Jul. 02, 2021	$ 127	158,793	(256)	12,149	170,813
Balances (in shares) at Jul. 02, 2021	12,713
Increase (Decrease) in Stockholders' Equity
Shares of common stock issued in connection with employee stock purchase plan	$ 1	1,270			1,271
Shares of common stock issued in connection with employee stock purchase plan (in shares)	40
Shares of common stock issued in connection with incentive stock plan		369			369
Shares of common stock issued in connection with incentive stock plan (in shares)	35
Issuance of restricted stock award and units (in shares)	1
Stock-based compensation expense		4,210			4,210
Net income (loss)				840	840
Net unrealized gain (loss) on derivative contracts			111		111
Balances at Oct. 01, 2021	$ 128	$ 164,642	$ (145)	$ 12,989	$ 177,614
Balances (in shares) at Oct. 01, 2021	12,789				12,789

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020
Cash flows from operating activities:
Net income (loss)	$ (7,527)	$ (10,499)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	12,678	14,324
Deferred income taxes, net	(3,544)	(4,389)
(Gain) loss on sale/disposal of equipment	(37)	(15)
Provision for doubtful accounts	87	1,066
Stock-based compensation	14,349	12,803
Accretion and fair value adjustments of contingent consideration	860	2,059
Changes in operating assets and liabilities, net of effects from business acquisitions:
Accounts receivable	(1,892)	5,016
Contract assets	(3,318)	33,591
Other receivables	376	(581)
Prepaid expenses and other current assets	2,005	1,387
Other assets	(4,557)	366
Accounts payable	(17,787)	(70)
Accrued liabilities	5,726	(30,034)
Contract liabilities	1,016	1,594
Right-of-use assets	(145)	259
Net cash (used in) provided by operating activities	(1,710)	26,877
Cash flows from investing activities:
Purchase of equipment and leasehold improvements	(4,898)	(3,976)
Proceeds from sale of equipment	46	19
Net cash used in investing activities	(4,852)	(3,957)
Cash flows from financing activities:
Payments on contingent consideration	(6,615)	(1,433)
Payments on notes payable	(1,724)	(187)
Payments on debt issuance costs		(327)
Proceeds from notes payable	206
Borrowings under term loan facility and line of credit		24,000
Repayments under term loan facility and line of credit	(9,750)	(38,750)
Principal payments on finance leases	(440)	(435)
Proceeds from stock option exercise	1,747	652
Proceeds from sales of common stock under employee stock purchase plan	2,656	2,224
Cash used to pay taxes on stock grants	(3,117)	(2,879)
Restricted Stock Award and Units	(1)	1
Net cash used in financing activities	(17,038)	(17,134)
Net increase (decrease) in cash and cash equivalents	(23,600)	5,786
Cash and cash equivalents at beginning of period	28,405	5,452
Cash and cash equivalents at end of period	4,805	11,238
Cash paid during the period for:
Interest	2,701	4,256
Income taxes	(1,742)	284
Supplemental disclosures of noncash investing and financing activities:
(Gain) loss on cash flow hedge valuations, net of tax	343	(206)
Equipment acquired under finance leases	$ 987	$ 394

ORGANIZATION AND OPERATIONS OF

ORGANIZATION AND OPERATIONS OF THE COMPANY	9 Months Ended
	Oct. 01, 2021
ORGANIZATION AND OPERATIONS OF THE COMPANY
ORGANIZATION AND OPERATIONS OF THE COMPANY	1. ORGANIZATION AND OPERATIONS OF THE COMPAN Y Willdan Group, Inc. (“Willdan” or the “Company”) is a provider of professional, technical and consulting services to utilities, private industry, and public agencies at all levels of government. As resources and infrastructures undergo continuous change, the Company helps organizations and their communities evolve and thrive by providing a wide range of technical services for energy solutions and government infrastructure. Through engineering, program management, policy advisory, and software and data management, the Company designs and delivers trusted, comprehensive, innovative, and proven solutions to improve efficiency, resiliency, and sustainability in energy and infrastructure. The Company’s broad portfolio of services operates within two financial reporting segments: (1) Energy and (2) Engineering and Consulting. The interfaces and synergies between these segments are important elements of the Company’s strategy to design and deliver trusted, comprehensive, innovative, and proven solutions for its customers. ​ The accounting policies followed by the Company are set forth in Part II, Item 8, Note 1, Organization and Operations of the Company Fiscal Years The Company operates and reports its annual financial results based on 52 or 53-week periods ending on the Friday closest to December 31. The Company operates and reports its quarterly financial results based on the 13-week period ending on the Friday closest to June 30, September 30, and December 31 and the 13 or 14-week period ending on the Friday closest to March 31, as applicable. Fiscal year 2021, which ends on December 31, 2021, will be comprised of 52 weeks, with all quarters consisting of 13 weeks each. Fiscal year 2020, which ended on January 1, 2021 was comprised of 53 weeks, with the first quarter consisting of 14 weeks and the remaining quarters consisting of 13 weeks each. All references to years in the notes to consolidated financial statements represent fiscal years. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements. Estimates also affect the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates. Impact of Covid-19 The coronavirus (“Covid-19”) pandemic and efforts to limit its spread negatively impacted the Company’s operations during its fiscal year 2020 and continued to impact the Company, albeit to a lesser extent, through the nine months ended October 1, 2021. In California and New York, the states in which the Company has historically derived a majority of its revenue, mandatory shutdown orders were issued in March 2020. In New York, phased re-openings began in June 2020, and all of the Company’s New York utility programs have restarted. In California, phased re-openings began in May 2020, followed by periods of curtailments as a result of resurgences of Covid-19 cases, and subsequent re-openings. As a result, the most significant pandemic related impacts to the Company’s business occurred in California to its direct install business. During the last week of June 2021, the Company’s largest program for the Los Angeles Department of Water and Power (“LADWP”) resumed, which was the Company’s last program suspended due to Covid-19. In addition, as of November 3, 2021, none of the Company’s contracts have been cancelled due to Covid-19. ​ In the Energy segment, the Company has experienced a negative impact on its direct install programs that serve small businesses as a result of restrictions put in place by governmental authorities that required temporary shutdowns of all “non-essential” businesses which resulted in a significant portion of the Company’s direct install work on these programs being suspended for varying periods of time during fiscal year 2020 and continuing in California through the Company’s first half of fiscal 2021. During non-Covid-19 impacted years, such as fiscal year 2019, the Company derived approximately 40% of its gross revenue from its direct install programs that serve small businesses and 60% from the Company’s other programs. The Company’s other programs are either businesses that have been determined to be “essential” by government authorities or have continued to progress during the pandemic. ​ In the Engineering and Consulting segment, the Company’s revenues have been less affected by Covid-19 than the revenues in the Energy segment. The services in this segment have generally been deemed “essential” by the government and have continued to operate while abiding social distancing measures. ​ The Company has continuously monitored its liquidity position during the Covid-19 pandemic in order to be flexible during these uncertain times and to position itself to resume its growth trajectory as work restrictions are lifted. As part of this effort ​ Asset and liability valuation and other estimates used in preparation of financial statements Impact on Clients and Subcontractors and Other Risks The Company primarily works for utilities, municipalities and other public agencies. Some of these customers could experience significant budget shortfalls for the current year and beyond as a result of the measures taken to mitigate the Covid-19 pandemic and/or revenue shortfalls as a result of reduced economic activity. Although none of the Company’s contracts with governmental or public agencies were materially modified during its fiscal year 2020 or during its nine months ended October 1, 2021, these potential budget deficits could result in delayed funding for existing contracts with the Company, postponements of new contracts or price concessions. Further, most of the Company’s clients are not committed to purchase any minimum amount of services, as the Company agreements with them are based on a “purchase order” or “master service agreement” model. As a result, they may discontinue utilizing some or all of the Company’s services with little or no notice. In addition, the Company relies on subcontractors and material suppliers to complete a substantial portion of its work, especially in its Energy segment. If the Company’s significant subcontractors and material suppliers suffer significant economic harm and must limit or cease operations or file for bankruptcy as a result of the current economic slowdown, the Company’s subcontractors and material suppliers may not be able to fulfill their contractual obligations satisfactorily and the Company may not have the ability to select its subcontractors and material suppliers of choice for new contracts. If the Company’s subcontractors and material suppliers are not able to fulfill their contractual obligations, it could result in a significant increase in costs for the Company to complete the projects or cause significant delays to the realization of revenues under those projects. The ultimate impact of Covid-19 on the Company’s financial condition and results of operations will depend on all of the factors noted above, including other factors that the Company may not be able to forecast at this time. See the risk factor “ The Covid-19 pandemic and health and safety measures intended to slow its spread have adversely affected, and may continue to adversely affect, our business, results of operations and financial condition. Health and Safety In response to the Covid-19 pandemic, the Company has taken and will continue to take precautionary measures intended to help minimize the risk of Covid-19 to its employees, including requiring the majority of its employees to work remotely, suspending non-essential travel and restricting in-person work-related meetings. The Company expects to continue to implement these measures until it has determined that the Covid-19 pandemic is adequately contained for purposes of its business, and may take further actions as government authorities require or recommend or as it determines to be in the best interests of its employees, customers, business partners and third-party service providers. ​

RECENT ACCOUNTING PRONOUNCEMENT

RECENT ACCOUNTING PRONOUNCEMENTS	9 Months Ended
	Oct. 01, 2021
RECENT ACCOUNTING PRONOUNCEMENTS
RECENT ACCOUNTING PRONOUNCEMENTS	2. RECENT ACCOUNTING PRONOUNCEMENTS Accounting Pronouncements Recently Adopted In December 2019, the FASB issued ASU No. 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes” (“ASU 2019-12”). ASU 2019-12 amends the accounting for income taxes by, among other things, removing: (i) The exception to the incremental approach for intraperiod tax allocation when there is a loss from continuing operations and income or a gain from other items (for example, discontinued operations or other comprehensive income); (ii) The exception to the requirement to recognize a deferred tax liability for equity method investments when a foreign subsidiary becomes an equity method investment; (iii) The exception to the ability not to recognize a deferred tax liability for a foreign subsidiary when a foreign equity method investment becomes a subsidiary; and (iv) The exception to the general methodology for calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year. The Company adopted this standard effective January 2, 2021. The adoption of this standard did not have a material impact to the Company’s Condensed Consolidated Financial Statements. Accounting Pronouncements Recently Issued In March 2020, the FASB issued ASU No. 2020-04, “Reference Rate Reform (Topic 848): facilitation of the Effects of Reference Rate Reform on Financial Reporting” (“ASU 2020-04”). ASU 2020-04 provides optional expedients and exceptions for applying U.S. GAAP to contract modifications and hedging relationships that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. ASU 2020-04 provides, among other things, guidance that modifications of contracts within the scope of Topic 470, Debt, should be accounted for by prospectively adjusting the effective interest rate; modifications of contracts within the scope of Topic 840, Leases, should be accounted for as a continuation of the existing contract; and, changes in the critical terms of hedging relationships, caused by reference rate reform, should not result in the de-designation of the instrument, provided certain criteria are met. In January 2021, the FASB issued ASU No. 2021-01, “Reference Rate Reform (Topic 848) - Scope” (“ASU 2021-01”). ASU 2021-01 clarifies the scope and application of ASU 2020-04 and permits entities, among other things, to elect certain optional expedients and exceptions when accounting for derivative contracts and certain hedging relationships affected by changes in the interest rates used for discounting cash flows. The Company’s exposure to LIBOR rates includes its credit facilities and swap agreement. The amendments are effective as of March 12, 2020 through December 31, 2022. Adoption is permitted at any time. The Company is currently evaluating the impact this update will have on its Condensed Consolidated Financial Statements. ​

REVENUES

REVENUES	9 Months Ended
	Oct. 01, 2021
REVENUES
REVENUES	3. REVENUES The Company enters into contracts with its clients that contain various types of pricing provisions, including fixed price, time-and-materials, and unit-based provisions. The Company recognizes revenues in accordance with ASU 2014-09, Revenue from Contracts with Customer, codified as ASC Topic 606 and the related amendments (collectively “ASC 606”). As such, the Company identifies a contract with a customer, identifies the performance obligations in the contract, determines the transaction price, allocates the transaction price to each performance obligation in the contract and recognizes revenues when (or as) the Company satisfies a performance obligation. The following table reflects the Company’s two reportable segments and the types of contracts that each most commonly enters into for revenue generating activities. ​ Segment Contract Type Revenue Recognition Method ​ Time-and-materials Time-and-materials Energy Unit-based Unit-based ​ Software license Unit-based ​ Fixed price Percentage-of-completion ​ Time-and-materials Time-and-materials Engineering and Consulting Unit-based Unit-based ​ Fixed price Percentage-of-completion ​ Revenue on the vast majority of the Company’s contracts is recognized over time because of the continuous transfer of control to the customer. Revenue on fixed price contracts is recognized on the percentage-of-completion method based generally on the ratio of direct costs incurred-to-date to estimated total direct costs at completion. The Company uses the percentage-of-completion method to better match the level of work performed at a certain point in time in relation to the effort that will be required to complete a project. In addition, the percentage-of-completion method is a common method of revenue recognition in the Company’s industry. Many of the Company’s fixed price contracts involve a high degree of subcontracted fixed price effort and are relatively short in duration, thereby lowering the risks of not properly estimating the percent complete. Revenue on time-and-materials and unit-based contracts is recognized as the work is performed in accordance with the specific rates and terms of the contract. The Company recognizes revenues for time-and-materials contracts based upon the actual hours incurred during a reporting period at contractually agreed upon rates per hour and also includes in revenue all reimbursable costs incurred during a reporting period. Certain of the Company’s time-and-materials contracts are subject to maximum contract values and, accordingly, when revenue is expected to exceed the maximum contract value, these contracts are generally recognized under the percentage-of-completion method, consistent with fixed price contracts. For unit-based contracts, the Company recognizes the contract price of units of a basic production product as revenue when the production product is delivered during a period. Revenue for amounts that have been billed but not earned is deferred, and such deferred revenue is referred to as contract liabilities in the accompanying condensed consolidated balance sheets. The Company also derives revenue from software licenses and professional services and maintenance fees. In accordance with ASC 606, the Company performs an assessment of each contract to identify the performance obligations, determine the overall transaction price for the contract, allocate the transaction price to the performance obligations, and recognize the revenue when the performance obligations are satisfied. The Company utilizes the residual approach by which it estimates the standalone selling price by reference to the total transaction price less the sum of the observable standalone selling prices of other goods or services promised in the contract. The software license revenue is typically recognized at a point in time when control is transferred to the client, which is defined as the point in time when the client can use and benefit from the license. The software license is delivered before related services are provided and is functional without services, updates, or technical support. Related professional services include training and support services in which the standalone selling price is determined based on an input measure of hours incurred to total estimated hours and is recognized over time, usually which is the life of the contract. To determine the proper revenue recognition method for contracts, the Company evaluates whether two or more contracts should be combined and accounted for as one single contract and whether the combined contract should be accounted for as one performance obligation. With respect to the Company’s contracts, it is rare that multiple contracts should be combined into a single performance obligation. This evaluation requires significant judgment and the decision to combine a group of contracts or separate a single contract into multiple performance obligations could change the amount of revenue and profit recorded in a given period. Contracts are considered to have a single performance obligation if the promise to transfer the individual goods or services is not separately identifiable from other promises in the contracts, which is mainly because the Company provides a significant service of integrating a complex set of tasks and components into a single project or capability. The Company may enter into contracts that include separate phases or elements. If each phase or element is negotiated separately based on the technical resources required and/or the supply and demand for the services being provided, the Company evaluates if the contracts should be segmented. If certain criteria are met, the contracts would be segmented which could result in revenues being assigned to the different elements or phases with different rates of profitability based on the relative value of each element or phase to the estimated total contract revenue. Segmented contracts may comprise up to approximately 2.0% to 3.0% of the Company’s consolidated contract revenue. Contracts that cover multiple phases or elements of the project or service lifecycle (development, construction and maintenance and support) may be considered to have multiple performance obligations even when they are part of a single contract. For contracts with multiple performance obligations, the Company allocates the transaction price to each performance obligation using the best estimate of the standalone selling price of each distinct good or service in the contract. For the periods presented, the value of the separate performance obligations under contracts with multiple performance obligations (generally measurement and verification tasks under certain energy performance contracts) were not material. In cases where the Company does not provide the distinct good or service on a standalone basis, the primary method used to estimate standalone selling price is the expected cost plus a margin approach, under which the Company forecasts the Company’s expected costs of satisfying a performance obligation and then adds an appropriate margin for the distinct good or service. The Company provides quality of workmanship warranties to customers that are included in the sale and are not priced or sold separately or do not provide customers with a service in addition to assurance of compliance with agreed-upon specifications and industry standards. The Company does not consider these types of warranties to be separate performance obligations. In some cases, the Company has a master service or blanket agreement with a customer under which each task order releases the Company to perform specific portions of the overall scope in the service contract. Each task order is typically accounted for as a separate contract because the task order establishes the enforceable rights and obligations, and payment terms. Under ASC 606, variable consideration should be considered when determining the transaction price and estimates should be made for the variable consideration component of the transaction price, as well as assessing whether an estimate of variable consideration is constrained. For certain of the Company’s contracts, variable consideration can arise from modifications to the scope of services resulting from unapproved change orders or customer claims. Variable consideration is included in the transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is resolved. The Company estimates of variable consideration and determination of whether to include estimated amounts in the transaction price are based largely on assessments of legal enforceability, the Company’s performance, and all information (historical, current and forecasted) that is reasonably available to the Company. Due to the nature of the work required to be performed on many of the Company’s performance obligations, the estimation of total revenue and cost at completion is complex, subject to many variables and requires significant judgment. As a significant change in one or more of these estimates could affect the profitability of the Company’s contracts, the Company reviews and updates the Company’s contract-related estimates regularly through a company-wide disciplined project review process in which management reviews the progress and execution of the Company’s performance obligations and the estimate at completion (EAC). As part of this process, management reviews information including, but not limited to, any outstanding key contract matters, progress towards completion and the related program schedule and the related changes in estimates of revenues and costs. Management must make assumptions and estimates regarding labor productivity and availability, the complexity of the work to be performed, the cost and availability of materials, the performance of subcontractors, and the availability and timing of funding from the customer, among other variables. The Company recognizes adjustments in estimated profit on contracts under the cumulative catch-up method. Under this method, the impact of the adjustment on profit recorded to date is recognized in the period the adjustment is identified. Revenue and profit in future periods of contract performance is recognized using the adjusted estimate. If at any time the estimate of contract profitability indicates an anticipated loss on the contract, the Company recognizes the full amount of estimated loss in the period it is identified. Contracts are often modified to account for changes in contract specifications and requirements. The Company considers contract modifications to exist when the modification either creates new rights or obligations or changes the existing enforceable rights or obligations. Most of the Company’s contract modifications are for goods or services that are not distinct from existing contracts due to the significant integration provided in the context of the contract and are accounted for as if they were part of the original contract. The effect of a contract modification that is not distinct from the existing contract on the transaction price and the Company’s measure of progress for the performance obligation to which it relates is recognized as an adjustment to revenue (either as an increase in or a reduction of revenue) on a cumulative catch-up basis. For contract modifications that result in the promise to deliver goods or services that are distinct from the existing contract and the increase in price of the contract is for the same amount as the standalone selling price of the additional goods or services included in the modification, the Company accounts for such contract modifications as a separate contract. The Company includes claims to vendors, subcontractors and others as a receivable and a reduction in recognized costs when enforceability of the claim is established by the contract and the amounts are reasonably estimable and probable of being recovered. The amounts are recorded up to the extent of the lesser of the amounts management expects to recover or to costs incurred. Billing practices are governed by the contract terms of each project based upon costs incurred, achievement of milestones or pre-agreed schedules. Billings do not necessarily correlate with revenue recognized using the percentage-of-completion method of revenue recognition. Direct costs of contract revenue consist primarily of that portion of technical and nontechnical salaries and wages that has been incurred in connection with revenue producing projects. Direct costs of contract revenue also include production expenses, subcontractor services and other expenses that are incurred in connection with revenue producing projects. Direct costs of contract revenue exclude that portion of technical and nontechnical salaries and wages related to marketing efforts, vacations, holidays and other time not spent directly generating revenue under existing contracts. Such costs are included in general and administrative expenses. Additionally, payroll taxes, bonuses and employee benefit costs for all Company personnel are included in general and administrative expenses in the accompanying consolidated statements of comprehensive income since no allocation of these costs is made to direct costs of contract revenue. No allocation of facilities costs is made to direct costs of contract revenue. Other companies may classify as direct costs of contract revenue some of the costs that the Company classifies as general and administrative costs. The Company expenses direct costs of contract revenue when incurred. Included in revenue and costs are all reimbursable costs for which the Company has the risk or on which the fee was based at the time of bid or negotiation. No revenue or cost is recorded for costs in which the Company acts solely in the capacity of an agent and has no risks associated with such costs. Accounts receivable are carried at original invoice amount less an estimate made for doubtful accounts based upon a review of all outstanding amounts on a quarterly basis. Management determines allowances for doubtful accounts through specific identification of amounts considered to be uncollectible and potential write-offs, plus a non-specific allowance for other amounts for which some potential loss has been determined to be probable based on current and past experience. The Company’s historical credit losses have been minimal with governmental entities and large public utilities, but disputes may arise related to these receivable amounts. Accounts receivable are written off when deemed uncollectible. Recoveries of accounts receivable previously written off are recorded when received. Retainage, included in contract assets, represents amounts withheld from billings to the Company’s clients pursuant to provisions in the contracts and may not be paid to the Company until specific tasks are completed or the project is completed and, in some instances, for even longer periods. As of October 1, 2021 and January 1, 2021, contract assets included retainage of approximately $4.9 million and $6.2 million, respectively. ​

SUPPLEMENTAL FINANCIAL STATEMEN

SUPPLEMENTAL FINANCIAL STATEMENT DATA	9 Months Ended
	Oct. 01, 2021
SUPPLEMENTAL FINANCIAL STATEMENT DATA
SUPPLEMENTAL FINANCIAL STATEMENT DATA	4. SUPPLEMENTAL FINANCIAL STATEMENT DATA Accounts Receivable From time to time, in connection with factoring agreements, the Company sells trade accounts receivable without recourse to third party purchasers in exchange for cash. During the nine months ended October 1, 2021, the Company sold trade accounts receivable and received cash proceeds of $8.0 million. The discounts on the trade accounts receivable sold were $0.8 million and were recorded within “Other, net” in other income (expense) in the condensed consolidated financial statements. During the nine months ended October 2, 2020, the Company did not sell any trade accounts receivable. Equipment and Leasehold Improvements ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 1, ​ January 1, ​ 2021 2021 ​ ​ (in thousands) Furniture and fixtures ​ $ 4,070 ​ $ 4,088 Computer hardware and software ​ 22,838 ​ 18,047 Leasehold improvements ​ 3,008 ​ 2,994 Equipment under finance leases ​ 3,084 ​ 2,370 Automobiles, trucks, and field equipment ​ 3,106 ​ 3,216 Subtotal ​ 36,106 ​ 30,715 Accumulated depreciation and amortization ​ (21,746) ​ (18,209) Equipment and leasehold improvements, net ​ $ 14,360 ​ $ 12,506 ​ Included in accumulated depreciation and amortization is $0.4 million and $0.6 million of amortization expense related to equipment held under finance leases for the nine months ended October 1, 2021 and for fiscal year 2020, respectively. Accrued Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 1, ​ January 1, ​ 2021 2021 ​ ​ (in thousands) Accrued subcontractor costs ​ $ 21,495 ​ $ 19,124 Other ​ 10,965 ​ 11,981 Accrued bonuses ​ ​ 7,852 ​ ​ 5,211 Compensation and payroll taxes ​ 3,224 ​ 1,983 Employee withholdings ​ 3,140 ​ 2,768 Paid leave bank ​ 509 ​ 687 Total accrued liabilities ​ $ 47,185 ​ $ 41,754 ​ Goodwill ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 1, ​ Additional ​ Additions / ​ October 1, ​ 2021 Purchase Cost Adjustments 2021 ​ ​ (in thousands) Reporting Unit: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Energy ​ $ 129,375 ​ $ — ​ $ — ​ $ 129,375 Engineering and Consulting ​ ​ 749 ​ ​ — ​ ​ — ​ ​ 749 ​ ​ $ 130,124 ​ $ — ​ $ — ​ $ 130,124 ​ Intangible Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 1, 2021 ​ January 1, 2021 ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ Accumulated ​ Gross ​ Accumulated ​ Amortization ​ Amount Amortization Amount Amortization Period ​ ​ (in thousands) ​ (in years) Finite: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Backlog ​ $ 7,944 ​ $ 6,978 ​ $ 7,944 ​ $ 6,249 ​ 1.0 Tradename ​ 15,911 ​ 8,494 ​ 15,911 ​ 6,984 2.5 ​ - ​ 6.0 Non-compete agreements ​ ​ 1,420 ​ ​ 1,407 ​ ​ 1,420 ​ ​ 1,390 ​ 4.0 ​ - ​ 5.0 Developed technology ​ ​ 15,500 ​ ​ 8,240 ​ ​ 15,500 ​ ​ 6,107 ​ 8.0 Customer relationships ​ ​ 58,149 ​ ​ 18,516 ​ ​ 58,149 ​ ​ 14,248 ​ 5.0 ​ - ​ 8.0 Total finite intangible assets ​ ​ 98,924 ​ $ 43,635 ​ ​ 98,924 ​ $ 34,978 ​ ​ ​ ​ ​ ​ In-process research and technology (1) ​ ​ 310 ​ ​ — ​ ​ 310 ​ ​ — ​ ​ ​ ​ ​ ​ Total intangible assets ​ $ 99,234 ​ $ 43,635 ​ $ 99,234 ​ $ 34,978 ​ ​ ​ ​ ​ ​ (1) In-process research and technology will not be amortized until put into use. ​

DERIVATIVE FINANCIAL INSTRUMENT

DERIVATIVE FINANCIAL INSTRUMENTS	9 Months Ended
	Oct. 01, 2021
DERIVATIVE FINANCIAL INSTRUMENTS
DERIVATIVE FINANCIAL INSTRUMENTS	5. DERIVATIVE FINANCIAL INSTRUMENTS The Company uses certain interest rate derivative contracts to hedge interest rate exposures on its variable rate debt. The Company’s hedging program is not designated for trading or speculative purposes. The Company recognizes derivative instruments as either assets or liabilities on the accompanying consolidated balance sheets at fair value. The Company records changes in the fair value (i.e., gains or losses) of the derivatives that have been designated as cash flow hedges in its consolidated balance sheets as accumulated other comprehensive income (loss) and in its condensed consolidated statements of comprehensive (loss) income as a loss or gain on cash flow hedge valuation. On January 31, 2019, the Company entered into an interest rate swap agreement that the Company designated as cash flow hedge to fix the variable interest rate on a portion of the Company’s Term A Loan (as defined below in Note 6. “ Debt Obligations The fair values of the Company’s outstanding derivatives designated as hedging instruments were as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value of Derivative ​ ​ Instruments as of ​ ​ Balance Sheet Location ​ October 1, 2021 ​ January 1, 2021 ​ ​ ​ ​ (in thousands) Interest rate swap agreement ​ Accrued liabilities ​ $ (201) ​ $ (624) Interest rate swap agreement ​ Other noncurrent (liabilities) assets ​ $ — ​ $ (48) ​ The impact of the effective portions of derivative instruments in cash flow hedging relationships and fair million The accumulated balances and reporting period activities for the periods below related to reclassifications out of accumulated other comprehensive loss are summarized as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gain (Loss) on ​ Accumulated Other ​ Derivative Instruments Comprehensive Loss ​ ​ (in thousands) Balances at January 1, 2021 ​ $ (488) ​ $ (488) Other comprehensive loss before reclassifications ​ ​ 163 ​ ​ 163 Amounts reclassified from accumulated other comprehensive income: ​ ​ 0 ​ ​ 0 Income tax benefit (expense) related to derivative instruments ​ ​ (35) ​ ​ (35) Net current-period other comprehensive loss ​ ​ 128 ​ ​ 128 Balances at April 2, 2021 ​ $ (360) ​ $ (360) Other comprehensive loss before reclassifications ​ ​ 156 ​ ​ 156 Amounts reclassified from accumulated other comprehensive income: ​ ​ 0 ​ ​ 0 Income tax benefit (expense) related to derivative instruments ​ ​ (52) ​ ​ (52) Net current-period other comprehensive loss ​ ​ 104 ​ ​ 104 Balances at July 2, 2021 ​ $ (256) ​ $ (256) Other comprehensive loss before reclassifications ​ ​ 152 ​ ​ 152 Amounts reclassified from accumulated other comprehensive income: ​ ​ 0 ​ ​ 0 Income tax benefit (expense) related to derivative instruments ​ ​ (41) ​ ​ (41) Net current-period other comprehensive loss ​ ​ 111 ​ ​ 110 Balances at October 1, 2021 ​ $ (145) ​ $ (145) ​

DEBT OBLIGATIONS

DEBT OBLIGATIONS	9 Months Ended
	Oct. 01, 2021
DEBT OBLIGATIONS
DEBT OBLIGATIONS	6. DEBT OBLIGATIONS Debt obligations, excluding obligations under finance leases (see Note 7, Leases, ​ ​ ​ ​ ​ ​ ​ ​ ​ October 1, January 1, ​ ​ 2021 ​ 2021 ​ ​ (in thousands) Outstanding borrowings on Term A Loan ​ $ 77,500 ​ $ 85,000 Outstanding borrowings on Revolving Credit Facility ​ ​ — ​ ​ — Outstanding borrowings on Delayed Draw Term Loan ​ ​ 24,750 ​ ​ 27,000 Other debt agreements ​ ​ 478 ​ ​ 1,996 Total debt ​ ​ 102,728 ​ ​ 113,996 Issuance costs and debt discounts ​ ​ (646) ​ ​ (822) Subtotal ​ ​ 102,082 ​ ​ 113,174 Less current portion of long-term debt ​ 13,336 ​ 14,996 Long-term debt portion ​ $ 88,746 ​ $ 98,178 ​ Credit Facilities On June 26, 2019, the Company and certain of its subsidiaries entered into an Amended and Restated Credit Agreement (as amended by the First Amendment, dated as of August 15, 2019, the Second Amendment, dated as of November 6, 2019, and the Third Amendment, dated as of May 6, 2020, the “Credit Agreement”) with a syndicate of financial institutions as lenders and BMO Harris Bank, N.A. (“BMO”), as administrative agent. The Credit Agreement provides for (i) a $100.0 million secured term loan (the “Term A Loan”), (ii) up to $50.0 million in delayed draw secured term loans (the “Delayed Draw Term Loan”), and (iii) a $50.0 million secured revolving credit facility (the “Revolving Credit Facility” and, collectively with the Term A Loan and the Delayed Draw Term Loan, the “Credit Facilities”), each maturing on June 26, 2024. The Company’s obligations under the Credit Agreement are guaranteed by its present and future domestic subsidiaries, with limited exceptions. Prior to the Third Amendment to the Amended and Restated Credit Agreement, dated as of May 6, 2020 (the “Third Amendment”), the Credit Agreement required the Company to comply with certain financial covenants, including requiring that the Company maintain a (i) total leverage ratio (the “Leverage Ratio”), defined as the ratio of total funded debt to Adjusted EBITDA (as defined in the Credit Agreement), of no more than 3.50 to 1.00 through December 31, 2020, and 3.25 to 1.00 thereafter and (ii) fixed charge coverage ratio (“FCCR Ratio”), defined as the ratio of Adjusted EBITDA less Unfinanced Capital Expenditures (as defined in the Credit Agreement) to Fixed Charges (as defined in the Credit Agreement), of not less than 1.20 to 1.00, in each case tested quarterly. Pursuant to the Third Amendment, during the period from May 6, 2020 until July 2, 2021 (the “Initial Covenant Relief Period”), the maximum Leverage Ratio was increased and the covenant to maintain a minimum FCCR Ratio was replaced with a covenant to maintain a minimum Adjusted EBITDA (as defined in the Third Amendment). The Credit Agreement also contains other customary restrictive covenants including (i) restrictions on the incurrence of additional indebtedness and additional liens on property, (ii) restrictions on permitted acquisitions and other investments and (iii) limitations on asset sales, mergers and acquisitions. Further, the Credit Agreement limits the Company’s payment of future dividends and distributions and share repurchases by the Company. Subject to certain exceptions, borrowings under the Credit Agreement are also subject to mandatory prepayment from (a) any issuances of debt or equity securities, (b) any sale or disposition of assets, (c) insurance and condemnation proceeds (d) representation and warranty insurance proceeds related to insurance policies issued in connection with acquisitions and (e) excess cash flow. Pursuant to the Third Amendment, during the Initial Covenant Relief Period, no delayed draw term loans could be borrowed under the Credit Facilities and the Company was prohibited from engaging in share repurchases or making any Permitted Acquisitions (as defined in the Credit Agreement). Additionally, during the Initial Covenant Relief Period, the aggregate amount of all capital expenditures made by the Company could not exceed $7.0 million, and the Company was prohibited from making any earn-out payments if, after giving effect to such earn-out payment, the Company’s liquidity would be less than $5.0 million or the aggregate amount of all earn-out payments made by the Company during the Initial Covenant Relief Period would exceed $7.0 million. ​ As part of the Third Amendment, borrowings under the Credit Agreement bore interest (A) from March 5, 2020 until May 6, 2020 (the date of the Third Amendment), at a rate equal to one-month LIBOR plus 2.0%, (B) from May 6, 2020 until the date the administrative agent receives the Company’s financial statements for the quarter ended July 3, 2020, at a rate equal to one-month LIBOR, plus an applicable margin of 2.50% and (C) at all other times during the Initial Covenant Relief Period, at a rate equal to either, at the Company’s option, (i) the highest of the prime rate, the Federal Funds Rate plus 0.5% or one-month LIBOR plus 1.00% or (ii) one-month LIBOR, in each case plus an applicable margin ranging from 0.125% to 1.50% with respect to Base Rate borrowings and 1.125% to 2.50% with respect to LIBOR borrowings, depending on the Leverage Ratio; provided, that one-month LIBOR shall not be less than 0.75% during the Initial Covenant Relief Period. During the Initial Covenant Relief Period, the Company paid a commitment fee for the unused portion of the Revolving Credit Facility and the delayed draw term loan facility, which ranged from 0.15% to 0.45% per annum depending on the Leverage Ratio, and fees on the face amount of any letters of credit outstanding under the Revolving Credit Facility, which range from 0.84% to 2.50% per annum, in each case, depending on whether such letter of credit was a performance or financial letter of credit and the Leverage Ratio. The Credit Agreement includes customary events of default. ​ Fourth Amendment to the Credit Agreement ​ On April 30, 2021, the Company entered into the Fourth Amendment to the Amended and Restated Credit Agreement (the “Fourth Amendment”). The Fourth Amendment extends the Initial Covenant Relief Period from July 2, 2021 to and including the earlier of (i) April 1, 2022 and (ii) the last day of the fiscal quarter in which the Company delivers an irrevocable election to terminate the covenant relief granted by the Fourth Amendment (the “Second Covenant Relief Period,” and together with the Initial Covenant Relief Period, the “Amended Covenant Relief Period”). The Fourth Amendment also (A) establishes the minimum Adjusted EBITDA thresholds for the remainder of the Amended Covenant Relief Period, (B) increases the maximum Leverage Ratio the Company is permitted to maintain through the fiscal quarter ending on April 1, 2022, (C) removes the previous prohibition during the Initial Covenant Relief Period on the Company’s ability to make delayed draw term loan borrowings, (D) removes the previous prohibition during the Initial Covenant Relief Period on the Company’s ability to make Permitted Acquisitions (as defined in the Credit Agreement) and to purchase, redeem or otherwise acquire the Company’s common stock, in each case, subject to certain conditions, and (E) increases the maximum amount of earn-out payments the Company is permitted to make during the Amended Covenant Relief Period from $7.0 million to $17.0 million, provided that the Company’s liquidity would not be less than $10.0 million after giving effect to such earn-out payment. Additionally, during the remainder of the Amended Covenant Relief Period, the aggregate amount of all capital expenditures made by the Company may not exceed $15.0 million. ​ Pursuant to the Fourth Amendment, borrowings under the Credit Agreement will bear interest at all times other than during the Initial Covenant Relief Period, at either a Base Rate or LIBOR, each as defined in the Credit Agreement, at the Company’s option, and in each case plus an applicable margin, which applicable margin will range from 0.125% to 1.25% with respect to Base Rate borrowings and 1.125% to 2.25% with respect to LIBOR borrowings, depending on the Leverage Ratio; provided, that LIBOR cannot be less than 0.00%. The Company will also pay a commitment fee for the unused portion of the Revolving Credit Facility and the delayed draft term loan facility, which will range from 0.15% to 0.40% per annum depending on the Leverage Ratio, and fees on the face amount of any letters of credit outstanding under the Revolving Credit Facility, which will range from 0.84% to 1.688% per annum, in each case, depending on whether such letter of credit is a performance or financial letter of credit and the Leverage Ratio. ​ As of October 1, 2021, the Company was in compliance with all covenants contained in the Credit Agreement, as amended by the Fourth Amendment. Other Debt Agreements The Company’s other debt agreements are related to financed insurance premiums, a financed software agreement, and a utility customer agreement and are immaterial to the Company’s Condensed Consolidated Financial Statements. ​ ​

LEASES

LEASES	9 Months Ended
	Oct. 01, 2021
LEASES
LEASES	7. LEASES The Company leases certain office facilities under long-term, non-cancellable operating leases that expire at various dates through the year 2027. In addition, the Company is obligated under finance leases for certain furniture and office equipment that expire at various dates through the year 2026. From time to time, the Company enters into non-cancelable leases for some of our facility and equipment needs. These leases allow the Company to conserve cash by paying a monthly lease rental fee for the use of facilities and equipment rather than purchasing them. The Company’s leases have remaining terms ranging from one to eight years , some of which may include options to extend the leases for up to five years , and some of which may include options to terminate the leases within one year . Currently, all of the Company’s leases contain fixed payment terms. The Company may decide to cancel or terminate a lease before the end of its term, in which case we are typically liable to the lessor for the remaining lease payments under the term of the lease. Additionally, all of our month-to-month leases are cancelable by the Company or the lessor, at any time, and are not included in our right-of-use asset or lease liability. As of October 1, 2021, the Company had no leases with residual value guarantees. Typically, the Company has purchase options on the equipment underlying its long-term leases. The Company may exercise some of these purchase options when the need for equipment is on-going and the purchase option price is attractive. Nonperformance-related default covenants, cross-default provisions, subjective default provisions and material adverse change clauses contained in material lease agreements, if any, are also evaluated to determine whether those clauses affect lease classification in accordance with “ASC” Topic 842-10-25. Leases are accounted for as operating or financing leases, depending on the terms of the lease. ​ Financing Leases ​ The Company leases certain equipment under financing leases. The economic substance of the leases is a financing transaction for acquisition of equipment and leasehold improvements. Accordingly, the right-of-use assets for these leases are included in the balance sheets in equipment and leasehold improvements, net of accumulated depreciation, with a corresponding amount recorded in current portion of financing lease obligations or noncurrent portion of financing lease obligations, as appropriate. The financing lease assets are amortized over the life of the lease or, if shorter, the life of the leased asset, on a straight-line basis and included in depreciation expense. The interest associated with financing lease obligations is included in interest expense. Right-of-use assets Operating leases are included in right-of-use assets, and current portion of lease liability and noncurrent portion of lease liability, as appropriate. Right-of-use assets and lease liabilities are recognized based on the present value of the future minimum lease payments over the lease term at commencement date. As most of the Company’s leases do not provide an implicit rate to calculate present value, the Company determines this rate by estimating the Company’s incremental borrowing rate at the lease commencement date. The right-of-use asset also includes any lease payments made and initial direct costs incurred at lease commencement and excludes lease incentives. The Company’s lease terms may include options to extend or terminate the lease when it is reasonably certain that it will exercise that option. Lease expense for minimum lease payments is recognized on a straight-line basis over the lease term. ​ ​ The following is a summary of the Company’s lease expense: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ October 1, ​ October 2, ​ October 1, ​ October 2, ​ 2021 2020 2021 2020 ​ (in thousands) ​ (in thousands) Operating lease cost $ 1,596 ​ $ 1,761 ​ $ 4,941 ​ $ 5,269 Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of assets ​ 139 ​ ​ 146 ​ ​ 397 ​ ​ 456 Interest on lease liabilities ​ 9 ​ ​ 6 ​ ​ 22 ​ ​ 23 Total net lease cost $ 1,744 ​ $ 1,913 ​ $ 5,360 ​ $ 5,748 ​ The following is a summary of lease information presented on the Company’s consolidated balance sheet: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 1, January 1, ​ ​ ​ 2021 ​ 2021 ​ ​ ​ (in thousands) ​ Operating leases: ​ ​ ​ ​ ​ ​ ​ Right-of-use assets ​ $ 16,096 ​ $ 20,130 ​ ​ ​ ​ ​ ​ ​ Lease liability ​ $ 5,472 ​ $ 5,844 ​ Lease liability, less current portion ​ 11,842 ​ 15,649 ​ Total lease liabilities ​ $ 17,314 ​ $ 21,493 ​ ​ ​ ​ ​ ​ ​ Finance leases (included in equipment and leasehold improvements, net): ​ ​ ​ ​ ​ ​ ​ Equipment and leasehold improvements, net ​ $ 3,084 ​ $ 2,370 ​ Accumulated depreciation ​ (1,954) ​ (1,826) ​ Total equipment and leasehold improvements, net ​ $ 1,130 ​ $ 544 ​ ​ ​ ​ ​ ​ ​ ​ Finance lease obligations ​ $ 372 ​ $ 248 ​ Finance lease obligations, less current portion ​ ​ 659 ​ ​ 236 ​ Total finance lease obligations ​ $ 1,031 ​ $ 484 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average remaining lease term (in years): ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ 3.96 ​ ​ 4.40 ​ Finance Leases ​ ​ 2.63 ​ ​ 2.02 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average discount rate: ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ 4.34 % ​ 4.44 % Finance Leases ​ ​ 2.97 % ​ 3.74 % ​ Rent expense was $1.6 million and $5.2 million for the three and nine months ended October 1, 2021, respectively, as compared to $1.9 million and $5.7 million for the three and nine months ended October 2, 2020, respectively. ​ ​ The following is a summary of other information and supplemental cash flow information related to finance and operating leases: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ ​ October 1, ​ October 2, ​ ​ 2021 2020 ​ ​ (in thousands) Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ ​ Operating cash flow from operating leases ​ $ 5,115 ​ $ 5,162 Operating cash flow from finance leases ​ ​ 22 ​ ​ 23 Financing cash flow from finance leases ​ ​ 440 ​ ​ 435 ​ ​ ​ ​ ​ ​ ​ Right-of-use assets obtained in exchange for lease liabilities: ​ ​ ​ ​ ​ ​ Operating leases ​ $ 326 ​ $ 3,007 ​ The following is a summary of the maturities of lease liabilities as of October 1, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Finance ​ ​ (in thousands) ​ Fiscal year: ​ ​ ​ ​ ​ ​ ​ Remainder of 2021 ​ $ 1,511 ​ $ 99 ​ 2022 ​ 5,701 ​ 400 ​ 2023 ​ 4,254 ​ ​ 357 ​ 2024 ​ ​ 2,772 ​ ​ 166 ​ 2025 ​ ​ 2,129 ​ 38 ​ 2026 and thereafter ​ 2,484 ​ 14 ​ Total lease payments ​ $ 18,851 ​ $ 1,074 ​ Less: Imputed interest ​ (1,537) ​ ​ (43) ​ Total lease obligations ​ 17,314 ​ ​ 1,031 ​ Less: Current obligations ​ 5,472 ​ ​ 372 ​ Noncurrent lease obligations ​ $ 11,842 ​ $ 659 ​ ​ The imputed interest for finance lease obligations represents the interest component of finance leases that will be recognized as interest expense in future periods. The financing component for operating lease obligations represents the effect of discounting the operating lease payments to their present value. ​

COMMITMENTS AND VARIABLE INTERE

COMMITMENTS AND VARIABLE INTEREST ENTITIES	9 Months Ended
	Oct. 01, 2021
COMMITMENTS AND VARIABLE INTEREST ENTITIES
COMMITMENTS AND VARIABLE INTEREST ENTITIES	8. COMMITMENTS AND VARIABLE INTEREST ENTITIES Employee Benefit Plans The Company has a qualified profit sharing plan pursuant to Code Section 401(a) and qualified cash or deferred arrangement pursuant to Code Section 401(k) covering all employees. Employees may elect to contribute up to 50% of their compensation limited to the amount allowed by tax laws. Company contributions are made solely at the discretion of the Company’s board of directors. The Company also had a defined contribution plan (the “Plan”) covering employees who have completed three months of service and who have attained 21 years of age. The Company elected to make matching contributions equal to 50% of the participants’ contributions to the Plan up to 6% of the individual participant’s compensation. Under the defined contribution plan, the Company may make discretionary matching contributions to employee accounts. During the nine months ended October 1, 2021 and October 2, 2020, the Company made matching contributions of $1.6 million and $0.9 million, respectively. Variable Interest Entities On March 4, 2016, the Company and the Company’s wholly-owned subsidiary, WES, acquired substantially all of the assets of Genesys and assumed certain specified liabilities of Genesys (collectively, the “Purchase”) pursuant to an Asset Purchase and Merger Agreement, dated as of February 26, 2016 (the “Agreement”), by and among Willdan Group, Inc., WES, WESGEN (as defined below), Genesys and Ronald W. Mineo (“Mineo”) and Robert J. Braun (“Braun” and, together with Mineo, the “Genesys Shareholders”). On March 5, 2016, pursuant to the terms of the Agreement, WESGEN, Inc., a non-affiliated corporation (“WESGEN”), merged (the “Merger” and, together with the Purchase, the “Acquisition”) with Genesys, with Genesys remaining as the surviving corporation. Genesys was acquired to strengthen the Company’s power engineering capability in the northeastern U.S., and also to increase client exposure and experience with universities. Genesys continues to be a professional corporation organized under the laws of the State of New York, wholly-owned by one or more licensed engineers. Pursuant to New York law, the Company does not own capital stock of Genesys. The Company has entered into an agreement with the Shareholder of Genesys pursuant to which the Shareholder will be prohibited from selling, transferring or encumbering the Shareholder’s ownership interest in Genesys without the Company’s consent. Notwithstanding the Company’s rights regarding the transfer of Genesys’s stock, the Company does not have control over the professional decision making of Genesys’s engineering services. The Company has entered into an administrative services agreement with Genesys pursuant to which WES will provide Genesys with ongoing administrative, operational and other non-professional support services. Genesys pays WES a service fee, which consists of all of the costs incurred by WES to provide the administrative services to Genesys plus ten percent of such costs, as well as any other costs that relate to professional service supplies and personnel costs. As a result of the administrative services agreement, the Company absorbs the expected losses of Genesys through its deferral of Genesys’s service fees owed to WES. ​

SEGMENT AND GEOGRAPHICAL INFORM

SEGMENT AND GEOGRAPHICAL INFORMATION	9 Months Ended
	Oct. 01, 2021
SEGMENT AND GEOGRAPHICAL INFORMATION
SEGMENT AND GEOGRAPHICAL INFORMATION	9. SEGMENT AND GEOGRAPHICAL INFORMATION Segment Information The Company’s two segments are Energy and Engineering and Consulting, and the Company’s chief operating decision maker, which continues to be its chief executive officer, receives and reviews financial information in this format. There were no intersegment sales during the three and nine months ended October 1, 2021 and October 2, 2020. The Company’s chief operating decision maker evaluates the performance of each segment based upon income or loss from operations before income taxes. Certain segment asset information including expenditures for long-lived assets has not been presented as it is not reported to or reviewed by the chief operating decision maker. In addition, enterprise-wide service line contract revenue is not included as it is impracticable to report this information for each group of similar services. Financial information with respect to the reportable segments is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Engineering ​ Unallocated ​ ​ ​ ​ Consolidated ​ Energy & Consulting Corporate Intersegment Total ​ ​ (in thousands) Fiscal Three Months Ended October 1, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 81,523 ​ $ 16,774 ​ $ - ​ $ - ​ $ 98,297 Depreciation and amortization ​ ​ 4,023 ​ ​ 244 ​ ​ - ​ ​ - ​ ​ 4,267 Interest expense, net ​ ​ - ​ ​ - ​ ​ 937 ​ ​ - ​ ​ 937 Segment profit (loss) before income tax expense ​ ​ 2,138 ​ ​ 2,673 ​ ​ (4,207) ​ ​ - ​ ​ 604 Income tax expense (benefit) ​ ​ 610 ​ ​ 1,286 ​ ​ (2,132) ​ ​ - ​ ​ (236) Net income (loss) ​ ​ 1,529 ​ ​ 1,387 ​ ​ (2,076) ​ ​ - ​ ​ 840 Segment assets (1) ​ ​ 331,573 ​ ​ 23,134 ​ ​ 55,329 ​ ​ (23,130) ​ ​ 386,906 Fiscal Three Months Ended October 2, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 87,888 ​ $ 16,620 ​ $ - ​ $ - ​ $ 104,508 Depreciation and amortization ​ ​ 4,072 ​ ​ 267 ​ ​ - ​ ​ - ​ ​ 4,339 Interest expense, net ​ ​ 7 ​ ​ - ​ ​ 1,206 ​ ​ - ​ ​ 1,213 Segment profit (loss) before income tax expense ​ ​ 3,203 ​ ​ 2,757 ​ ​ (4,906) ​ ​ - ​ ​ 1,054 Income tax expense (benefit) ​ ​ (437) ​ ​ 1,300 ​ ​ (2,449) ​ ​ - ​ ​ (1,586) Net income (loss) ​ ​ 3,641 ​ ​ 1,457 ​ ​ (2,458) ​ ​ - ​ ​ 2,640 Segment assets (1) ​ ​ 348,350 ​ ​ 22,755 ​ ​ 50,481 ​ ​ (23,130) ​ ​ 398,456 Fiscal Nine Months Ended October 1, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 209,977 ​ $ 51,560 ​ $ - ​ $ - ​ $ 261,537 Depreciation and amortization ​ ​ 11,934 ​ ​ 744 ​ ​ - ​ ​ - ​ ​ 12,678 Interest expense, net ​ ​ 5 ​ ​ - ​ ​ 3,095 ​ ​ - ​ ​ 3,100 Segment profit (loss) before income tax expense ​ ​ (5,607) ​ ​ 7,507 ​ ​ (14,784) ​ ​ - ​ ​ (12,884) Income tax expense (benefit) ​ ​ (2,331) ​ ​ 3,122 ​ ​ (6,148) ​ ​ - ​ ​ (5,357) Net income (loss) ​ ​ (3,275) ​ ​ 4,386 ​ ​ (8,638) ​ ​ - ​ ​ (7,527) Segment assets (1) ​ ​ 331,573 ​ ​ 23,134 ​ ​ 55,329 ​ ​ (23,130) ​ ​ 386,906 Fiscal Nine Months Ended October 2, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 242,394 ​ $ 51,689 ​ $ - ​ $ - ​ $ 294,083 Depreciation and amortization ​ ​ 13,499 ​ ​ 825 ​ ​ - ​ ​ - ​ ​ 14,324 Interest expense, net ​ ​ 26 ​ ​ - ​ ​ 3,957 ​ ​ - ​ ​ 3,983 Segment profit (loss) before income tax expense ​ ​ (6,490) ​ ​ 7,953 ​ ​ (15,243) ​ ​ - ​ ​ (13,780) Income tax expense (benefit) ​ ​ (1,545) ​ ​ 1,894 ​ ​ (3,630) ​ ​ - ​ ​ (3,281) Net income (loss) ​ ​ (4,944) ​ ​ 6,059 ​ ​ (11,614) ​ ​ - ​ ​ (10,499) Segment assets (1) ​ ​ 348,350 ​ ​ 22,755 ​ ​ 50,481 ​ ​ (23,130) ​ ​ 398,456 (1) Segment assets are presented net of intercompany receivables. ​ The following tables provide information about disaggregated revenue by contract type, client type and geographical region: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended October 1, 2021 ​ Energy Engineering and Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 9,104 ​ $ 13,160 ​ $ 22,264 Unit-based ​ ​ 51,470 ​ ​ 2,650 ​ ​ 54,120 Fixed price ​ ​ 20,950 ​ ​ 963 ​ ​ 21,913 Total (1) ​ $ 81,524 ​ $ 16,773 ​ $ 98,297 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 7,741 ​ $ 1,568 ​ $ 9,309 Government ​ ​ 18,537 ​ ​ 15,181 ​ ​ 33,718 Utilities (2) ​ ​ 55,245 ​ ​ 24 ​ ​ 55,269 Total (1) ​ $ 81,524 ​ $ 16,773 ​ $ 98,297 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 81,524 ​ $ 16,773 ​ $ 98,297 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended October 1, 2021 ​ Energy Engineering and Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 25,060 ​ $ 40,444 ​ $ 65,504 Unit-based ​ ​ 132,688 ​ ​ 7,817 ​ ​ 140,505 Fixed price ​ ​ 52,229 ​ ​ 3,299 ​ ​ 55,528 Total (1) ​ $ 209,977 ​ $ 51,560 ​ $ 261,537 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 20,685 ​ $ 4,037 ​ $ 24,723 Government ​ ​ 45,766 ​ ​ 47,391 ​ ​ 93,157 Utilities (2) ​ ​ 143,525 ​ ​ 132 ​ ​ 143,657 Total (1) ​ $ 209,977 ​ $ 51,560 ​ $ 261,537 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 209,977 ​ $ 51,560 ​ $ 261,537 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended October 2, 2020 ​ Energy Engineering and Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 10,936 ​ $ 13,719 ​ $ 24,655 Unit-based ​ ​ 43,010 ​ ​ 2,082 ​ ​ 45,092 Fixed price ​ ​ 33,941 ​ ​ 820 ​ ​ 34,761 Total (1) ​ $ 87,887 ​ $ 16,621 ​ $ 104,508 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 10,737 ​ $ 1,300 ​ $ 12,037 Government ​ ​ 30,627 ​ ​ 14,657 ​ ​ 45,284 Utilities (2) ​ ​ 46,523 ​ ​ 664 ​ ​ 47,187 Total (1) ​ $ 87,887 ​ $ 16,621 ​ $ 104,508 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 87,887 ​ $ 16,621 ​ $ 104,508 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended October 2, 2020 ​ Energy Engineering and Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 37,072 ​ $ 41,499 ​ $ 78,571 Unit-based ​ ​ 122,800 ​ ​ 7,180 ​ ​ 129,979 Fixed price ​ ​ 82,522 ​ ​ 3,011 ​ ​ 85,531 Total (1) ​ $ 242,394 ​ $ 51,689 ​ $ 294,083 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 28,355 ​ $ 3,978 ​ $ 32,333 Government ​ ​ 74,056 ​ ​ 46,390 ​ ​ 120,446 Utilities (2) ​ ​ 139,983 ​ ​ 1,321 ​ ​ 141,304 Total (1) ​ $ 242,394 ​ $ 51,689 ​ $ 294,083 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 242,394 ​ $ 51,689 ​ $ 294,083 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (1) Amounts may not add to the totals due to rounding. (2) Includes the portion of revenue related to small business programs paid by the end user/customer. (3) Revenue from the Company’s foreign operations were not material for the three and nine months ended October 1, 2021 and October 2, 2020. ​ Geographical Information ​ Substantially all of the Company’s consolidated revenue was derived from its operations in the U.S. The Company operates through a network of offices spread across 24 U.S. states, the District of Columbia, and Canada. Revenues from the Company’s Canadian operations were not material for the three and nine months ended October 1, 2021 nor the three and nine months ended October 2, 2020. Customer Concentration For the three and nine months ended October 1, 2021, the Company’s top 10 customers accounted for 52.4%, and 46.8%, respectively, of the Company’s consolidated contract revenue. For the three and nine months ended October 2, 2020, the Company’s top 10 customers accounted for 46.7%, and 48.6%, respectively, of the Company’s consolidated contract revenue. For the three months ended October 1, 2021, the Company had one customer, Los Angeles Department of Water and Power (“LADWP”), that accounted for 17.0% of its consolidated contract revenues. On a segment basis, the Company had individual customers that accounted for more than 10% of its segment contract revenues. For the three months ended October 1, 2021, the Company derived 20.4% of its Energy segment revenues from one customer, LADWP. For the nine months ended October 1, 2021, the Company derived 21.5% of its Energy segment revenues from two customers, LADWP and Consolidated Edison of New York. For the three months ended October 1, 2021, no single customer accounted for 10% or more of . For the nine months ended October 1, 2021, the Company derived 12.2% of from one customer, the City of Elk Grove. For the three months ended October 2, 2020, no single customer accounted for 10% or more of its Energy segment revenues. For the nine months ended October 2, 2020, the Company derived 26.8% of its Energy segment revenues from two customers, LADWP and DASNY. For the three and nine months ended October 2, 2020, the Company derived 18.7% and 19.6% , respectively, of its Engineering and Consulting segment revenues from one customer, the City of Elk Grove. The Company’s largest clients are based in California and New York. For the three and nine months ended October 1, 2021, services provided to clients in California accounted for 38.9% and 36.2%, respectively, of the Company’s consolidated contract revenue and services provided to clients in New York accounted for 19.0% and 20.7%, respectively, of the Company’s consolidated contract revenue. For the three and nine months ended October 2, 2020, services provided to clients in California accounted for 32.3%, and 40.2%, respectively, of the Company’s consolidated contract revenue, and services provided to clients in New York accounted for 19.2%, and 18.4%, respectively, of the Company’s consolidated contract revenue.

INCOME TAXES

INCOME TAXES	9 Months Ended
	Oct. 01, 2021
INCOME TAXES
INCOME TAXES	10. INCOME TAXES Income taxes are accounted for under the asset and liability method. Deferred tax assets and liabilities are recognized for the future tax consequences of temporary differences between the financial reporting basis and tax basis of the Company’s assets and liabilities, subject to a judgmental assessment of the recoverability of deferred tax assets. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. A valuation allowance is recorded when it is more likely than not that some of the deferred tax assets may not be realized. Significant judgment is applied when assessing the need for valuation allowances and includes the evaluation of historical income (loss) adjusted for the effects of non-recurring items and the impact of recent business combinations. Areas of estimation include our consideration of future taxable income which is driven by verifiable signed contracts and ongoing prudent and feasible tax planning strategies. Should a change in circumstances lead to a change in judgment about the utilization of deferred tax assets in future years, the Company would adjust the related valuation allowances in the period that the change in circumstances occurs, along with a corresponding increase or charge to income. During each fiscal year, the Company assesses the available positive and negative evidence to evaluate if it is more likely than not that the deferred tax assets will be realized. Beginning in fiscal year 2017, the Company determined that it was more-likely-than-not that the entire California net operating loss will not be utilized prior to expiration. Significant pieces of objective evidence evaluated included the Company’s history of utilization of California net operating losses in prior years for each of its subsidiaries, as well as its forecasted amount of net operating loss utilization for certain members of the combined group. As a result, the Company recorded a valuation allowance in the amount of $86,000 at the end of fiscal year 2018 related to California net operating losses. As of October 1, 2021, the Company assessed all available positive and negative evidence available to determine whether, based on the weight of that evidence, there was a change in judgment related to the utilization of deferred tax assets in future years. The Company concluded that as of October 1, 2021, the valuation allowance for the Company’s deferred tax assets was appropriate in accordance with ASC 740. Consequently, there was no change to the valuation allowance during the nine months ended October 1, 2021. For the nine months ended October 2, 2020, the Company did not have a change in the valuation allowance. For acquired business entities, if the Company identifies changes to acquired deferred tax asset valuation allowances or liabilities related to uncertain tax positions during the measurement period and they relate to new information obtained about facts and circumstances that existed as of the acquisition date, those changes are considered a measurement period adjustment, and the Company records the offset to goodwill. The Company records all other changes to deferred tax asset valuation allowances and liabilities related to uncertain tax positions in current period income tax expense. The Company recognizes the tax benefit from uncertain tax positions if it is more likely than not that the tax positions will be sustained on examination by the tax authorities, based on the technical merits of the position. The tax benefit is measured based on the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement. The Company recognizes interest and penalties related to unrecognized tax benefits in income tax expense. As of October 1, 2021, the Company has not recorded a liability for uncertain tax positions. Based on the Company’s estimates and determination of an effective tax rate for the year, the Company recorded an income tax benefit of $0.2 million and $5.4 million for the three and nine months ended October 1, 2021, respectively, as compared to an income tax benefit of $1.6 million and $3.3 million for the three and nine months ended October 2, 2020, respectively. During the three and nine months ended October 1, 2021, the difference between the effective tax rate and the federal statutory rate was primarily attributable to state taxes, excess tax benefit on stock compensation, nondeductible executive compensation, research and development tax credits, the commercial building energy efficiency deduction, and additional benefits provided by the Coronavirus Aid, Relief, and Economic Security (CARES) Act (H.R. 748). For the three and nine months ended October 2, 2020, On March 27, 2020, President Trump signed into law the CARES Act, which includes a number of provisions relating to refundable payroll tax credits, deferment of employer side social security payments, net operating loss carryback periods, alternative minimum tax credit refunds, modifications to the net interest deduction limitations and technical corrections to tax depreciation methods for qualified improvement property. Under ASC 740, the effects of new legislation are recognized upon enactment. Accordingly, the effects of the CARES Act have been incorporated into the income tax provision computation for the three and nine months ended October 1, 2021 and October 2, 2020. The Company recognized a $0.7 million tax benefit related to the net operating loss carryback provisions of the CARES Act during the third quarter of fiscal 2021. On December 27, 2020, President Trump signed into law the Consolidated Appropriations Act, 2021 (CAA 2021) which included a number of provisions including, but not limited to the extension of numerous employment tax credits, the extension of the Section 179D deduction, enhanced business meals deductions, and the deductibility of expenses paid for with Paycheck Protection Program (PPP) loan funds that are forgiven. Accordingly, the effects of the CCA have been incorporated into the income tax provision computation for the three and nine months ended October 1, 2021. The extension of the energy efficiency building deduction under Section 179D resulted in the continuation of this additional benefit for the Company. ​

EARNINGS PER SHARE (EPS)

EARNINGS PER SHARE (EPS)	9 Months Ended
	Oct. 01, 2021
EARNINGS PER SHARE (EPS)
EARNINGS PER SHARE (EPS)	11. EARNINGS PER SHARE (“EPS”) Basic EPS is computed by dividing net income available to common stockholders by the weighted-average number of common shares outstanding. Diluted EPS is computed by dividing net income by the weighted-average number of common shares outstanding and dilutive potential common shares for the period. Potential common shares include the weighted-average dilutive effects of outstanding stock options and restricted stock awards using the treasury stock method. The following table sets forth the number of weighted-average common shares outstanding used to compute basic and diluted EPS: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ Nine months ended ​ ​ October 1, ​ October 2, ​ October 1, ​ October 2, ​ 2021 2020 2021 2020 ​ ​ (in thousands, except per share amounts) Net income (loss) ​ $ 840 ​ $ 2,640 ​ $ (7,527) ​ $ (10,499) Weighted-average common shares outstanding ​ 12,606 ​ 11,992 ​ 12,391 ​ 11,723 Effect of dilutive stock options and restricted stock awards ​ 535 ​ 425 ​ — ​ — Weighted-average common shares outstanding-diluted ​ 13,141 ​ 12,417 ​ 12,391 ​ 11,723 Earnings (Loss) per share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic ​ $ 0.07 ​ $ 0.22 ​ $ (0.61) ​ $ (0.90) Diluted ​ $ 0.06 ​ $ 0.21 ​ $ (0.61) ​ $ (0.90) ​ For the three months ended October 1, 2021 and October 2, 2020, the Company excluded common shares subject to outstanding equity awards from the calculation of diluted shares because their impact would have been anti-dilutive. For the nine months ended October 1, 2021 and October 2, 2020, the Company recorded net loss, and all shares subject to outstanding equity awards have been excluded from such periods because including them would be anti-dilutive. ​

CONTINGENCIES

CONTINGENCIES	9 Months Ended
	Oct. 01, 2021
CONTINGENCIES
CONTINGENCIES	12. CONTINGENCIES Claims and Lawsuits The Company is subject to claims and lawsuits from time to time, including those alleging professional errors or omissions that arise in the ordinary course of business against firms that operate in the engineering and consulting professions. The Company carries professional liability insurance, subject to certain deductibles and policy limits, for such claims as they arise and may from time to time establish reserves for litigation that is considered probable of a loss. In accordance with accounting standards regarding loss contingencies, the Company accrues an undiscounted liability for those contingencies where the incurrence of a loss is probable and the amount can be reasonably estimated, and discloses the amount accrued and an estimate of any reasonably possible loss in excess of the amount accrued, if such disclosure is necessary for the Company’s financial statements not to be misleading. The Company does not accrue liabilities when the likelihood that the liability has been incurred is probable but the amount cannot be reasonably estimated, or when the liability is believed to be only reasonably possible or remote. Because litigation outcomes are inherently unpredictable, the Company’s evaluation of legal proceedings often involves a series of complex assessments by management about future events and can rely heavily on estimates and assumptions. If the assessments indicate that loss contingencies that could be material to any one of the Company’s financial statements are not probable, but are reasonably possible, or are probable, but cannot be estimated, then the Company will disclose the nature of the loss contingencies, together with an estimate of the possible loss or a statement that such loss is not reasonably estimable. While the consequences of certain unresolved proceedings are not presently determinable, and a reasonable estimate of the probable and reasonably possible loss or range of loss in excess of amounts accrued for such proceedings cannot be made, an adverse outcome from such proceedings could have a material adverse effect on the Company’s earnings in any given reporting period. However, in the opinion of the Company’s management, after consulting with legal counsel, and taking into account insurance coverage, the ultimate liability related to current outstanding claims and lawsuits is not expected to have a material adverse effect on the Company’s financial statements. ​

SUBSEQUENT EVENTS

SUBSEQUENT EVENTS	9 Months Ended
	Oct. 01, 2021
SUBSEQUENT EVENTS
SUBSEQUENT EVENTS	13. SUBSEQUENT EVENTS ​ In accordance with ASC Topic 855, Subsequent Events, the Company evaluates subsequent events up until the date the condensed consolidated financial statements are issued. As of November 4, 2021, there were no subsequent events required to be reported. ​ ​

ORGANIZATION AND OPERATIONS O_2

ORGANIZATION AND OPERATIONS OF THE COMPANY (Policies)	9 Months Ended
	Oct. 01, 2021
ORGANIZATION AND OPERATIONS OF THE COMPANY
Basis of Presentation	​ The accounting policies followed by the Company are set forth in Part II, Item 8, Note 1, Organization and Operations of the Company
Fiscal Years	Fiscal Years The Company operates and reports its annual financial results based on 52 or 53-week periods ending on the Friday closest to December 31. The Company operates and reports its quarterly financial results based on the 13-week period ending on the Friday closest to June 30, September 30, and December 31 and the 13 or 14-week period ending on the Friday closest to March 31, as applicable. Fiscal year 2021, which ends on December 31, 2021, will be comprised of 52 weeks, with all quarters consisting of 13 weeks each. Fiscal year 2020, which ended on January 1, 2021 was comprised of 53 weeks, with the first quarter consisting of 14 weeks and the remaining quarters consisting of 13 weeks each. All references to years in the notes to consolidated financial statements represent fiscal years.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements. Estimates also affect the reported amounts of revenue and expenses during the reporting period. Actual results could differ from those estimates.
Impact of Covid-19	Impact of Covid-19 The coronavirus (“Covid-19”) pandemic and efforts to limit its spread negatively impacted the Company’s operations during its fiscal year 2020 and continued to impact the Company, albeit to a lesser extent, through the nine months ended October 1, 2021. In California and New York, the states in which the Company has historically derived a majority of its revenue, mandatory shutdown orders were issued in March 2020. In New York, phased re-openings began in June 2020, and all of the Company’s New York utility programs have restarted. In California, phased re-openings began in May 2020, followed by periods of curtailments as a result of resurgences of Covid-19 cases, and subsequent re-openings. As a result, the most significant pandemic related impacts to the Company’s business occurred in California to its direct install business. During the last week of June 2021, the Company’s largest program for the Los Angeles Department of Water and Power (“LADWP”) resumed, which was the Company’s last program suspended due to Covid-19. In addition, as of November 3, 2021, none of the Company’s contracts have been cancelled due to Covid-19. ​ In the Energy segment, the Company has experienced a negative impact on its direct install programs that serve small businesses as a result of restrictions put in place by governmental authorities that required temporary shutdowns of all “non-essential” businesses which resulted in a significant portion of the Company’s direct install work on these programs being suspended for varying periods of time during fiscal year 2020 and continuing in California through the Company’s first half of fiscal 2021. During non-Covid-19 impacted years, such as fiscal year 2019, the Company derived approximately 40% of its gross revenue from its direct install programs that serve small businesses and 60% from the Company’s other programs. The Company’s other programs are either businesses that have been determined to be “essential” by government authorities or have continued to progress during the pandemic. ​ In the Engineering and Consulting segment, the Company’s revenues have been less affected by Covid-19 than the revenues in the Energy segment. The services in this segment have generally been deemed “essential” by the government and have continued to operate while abiding social distancing measures. ​ The Company has continuously monitored its liquidity position during the Covid-19 pandemic in order to be flexible during these uncertain times and to position itself to resume its growth trajectory as work restrictions are lifted. As part of this effort ​ Asset and liability valuation and other estimates used in preparation of financial statements Impact on Clients and Subcontractors and Other Risks The Company primarily works for utilities, municipalities and other public agencies. Some of these customers could experience significant budget shortfalls for the current year and beyond as a result of the measures taken to mitigate the Covid-19 pandemic and/or revenue shortfalls as a result of reduced economic activity. Although none of the Company’s contracts with governmental or public agencies were materially modified during its fiscal year 2020 or during its nine months ended October 1, 2021, these potential budget deficits could result in delayed funding for existing contracts with the Company, postponements of new contracts or price concessions. Further, most of the Company’s clients are not committed to purchase any minimum amount of services, as the Company agreements with them are based on a “purchase order” or “master service agreement” model. As a result, they may discontinue utilizing some or all of the Company’s services with little or no notice. In addition, the Company relies on subcontractors and material suppliers to complete a substantial portion of its work, especially in its Energy segment. If the Company’s significant subcontractors and material suppliers suffer significant economic harm and must limit or cease operations or file for bankruptcy as a result of the current economic slowdown, the Company’s subcontractors and material suppliers may not be able to fulfill their contractual obligations satisfactorily and the Company may not have the ability to select its subcontractors and material suppliers of choice for new contracts. If the Company’s subcontractors and material suppliers are not able to fulfill their contractual obligations, it could result in a significant increase in costs for the Company to complete the projects or cause significant delays to the realization of revenues under those projects. The ultimate impact of Covid-19 on the Company’s financial condition and results of operations will depend on all of the factors noted above, including other factors that the Company may not be able to forecast at this time. See the risk factor “ The Covid-19 pandemic and health and safety measures intended to slow its spread have adversely affected, and may continue to adversely affect, our business, results of operations and financial condition. Health and Safety In response to the Covid-19 pandemic, the Company has taken and will continue to take precautionary measures intended to help minimize the risk of Covid-19 to its employees, including requiring the majority of its employees to work remotely, suspending non-essential travel and restricting in-person work-related meetings. The Company expects to continue to implement these measures until it has determined that the Covid-19 pandemic is adequately contained for purposes of its business, and may take further actions as government authorities require or recommend or as it determines to be in the best interests of its employees, customers, business partners and third-party service providers.

RECENT ACCOUNTING PRONOUNCEME_2

RECENT ACCOUNTING PRONOUNCEMENTS (Policies)	9 Months Ended
	Oct. 01, 2021
RECENT ACCOUNTING PRONOUNCEMENTS
Recent Accounting Pronouncements	Accounting Pronouncements Recently Adopted In December 2019, the FASB issued ASU No. 2019-12, “Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes” (“ASU 2019-12”). ASU 2019-12 amends the accounting for income taxes by, among other things, removing: (i) The exception to the incremental approach for intraperiod tax allocation when there is a loss from continuing operations and income or a gain from other items (for example, discontinued operations or other comprehensive income); (ii) The exception to the requirement to recognize a deferred tax liability for equity method investments when a foreign subsidiary becomes an equity method investment; (iii) The exception to the ability not to recognize a deferred tax liability for a foreign subsidiary when a foreign equity method investment becomes a subsidiary; and (iv) The exception to the general methodology for calculating income taxes in an interim period when a year-to-date loss exceeds the anticipated loss for the year. The Company adopted this standard effective January 2, 2021. The adoption of this standard did not have a material impact to the Company’s Condensed Consolidated Financial Statements. Accounting Pronouncements Recently Issued In March 2020, the FASB issued ASU No. 2020-04, “Reference Rate Reform (Topic 848): facilitation of the Effects of Reference Rate Reform on Financial Reporting” (“ASU 2020-04”). ASU 2020-04 provides optional expedients and exceptions for applying U.S. GAAP to contract modifications and hedging relationships that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. ASU 2020-04 provides, among other things, guidance that modifications of contracts within the scope of Topic 470, Debt, should be accounted for by prospectively adjusting the effective interest rate; modifications of contracts within the scope of Topic 840, Leases, should be accounted for as a continuation of the existing contract; and, changes in the critical terms of hedging relationships, caused by reference rate reform, should not result in the de-designation of the instrument, provided certain criteria are met. In January 2021, the FASB issued ASU No. 2021-01, “Reference Rate Reform (Topic 848) - Scope” (“ASU 2021-01”). ASU 2021-01 clarifies the scope and application of ASU 2020-04 and permits entities, among other things, to elect certain optional expedients and exceptions when accounting for derivative contracts and certain hedging relationships affected by changes in the interest rates used for discounting cash flows. The Company’s exposure to LIBOR rates includes its credit facilities and swap agreement. The amendments are effective as of March 12, 2020 through December 31, 2022. Adoption is permitted at any time. The Company is currently evaluating the impact this update will have on its Condensed Consolidated Financial Statements.

REVENUES (Policies)

REVENUES (Policies)	9 Months Ended
	Oct. 01, 2021
Revenues [Abstract]
Contract Accounting	The Company enters into contracts with its clients that contain various types of pricing provisions, including fixed price, time-and-materials, and unit-based provisions. The Company recognizes revenues in accordance with ASU 2014-09, Revenue from Contracts with Customer, codified as ASC Topic 606 and the related amendments (collectively “ASC 606”). As such, the Company identifies a contract with a customer, identifies the performance obligations in the contract, determines the transaction price, allocates the transaction price to each performance obligation in the contract and recognizes revenues when (or as) the Company satisfies a performance obligation. The following table reflects the Company’s two reportable segments and the types of contracts that each most commonly enters into for revenue generating activities. ​ Segment Contract Type Revenue Recognition Method ​ Time-and-materials Time-and-materials Energy Unit-based Unit-based ​ Software license Unit-based ​ Fixed price Percentage-of-completion ​ Time-and-materials Time-and-materials Engineering and Consulting Unit-based Unit-based ​ Fixed price Percentage-of-completion ​ Revenue on the vast majority of the Company’s contracts is recognized over time because of the continuous transfer of control to the customer. Revenue on fixed price contracts is recognized on the percentage-of-completion method based generally on the ratio of direct costs incurred-to-date to estimated total direct costs at completion. The Company uses the percentage-of-completion method to better match the level of work performed at a certain point in time in relation to the effort that will be required to complete a project. In addition, the percentage-of-completion method is a common method of revenue recognition in the Company’s industry. Many of the Company’s fixed price contracts involve a high degree of subcontracted fixed price effort and are relatively short in duration, thereby lowering the risks of not properly estimating the percent complete. Revenue on time-and-materials and unit-based contracts is recognized as the work is performed in accordance with the specific rates and terms of the contract. The Company recognizes revenues for time-and-materials contracts based upon the actual hours incurred during a reporting period at contractually agreed upon rates per hour and also includes in revenue all reimbursable costs incurred during a reporting period. Certain of the Company’s time-and-materials contracts are subject to maximum contract values and, accordingly, when revenue is expected to exceed the maximum contract value, these contracts are generally recognized under the percentage-of-completion method, consistent with fixed price contracts. For unit-based contracts, the Company recognizes the contract price of units of a basic production product as revenue when the production product is delivered during a period. Revenue for amounts that have been billed but not earned is deferred, and such deferred revenue is referred to as contract liabilities in the accompanying condensed consolidated balance sheets. The Company also derives revenue from software licenses and professional services and maintenance fees. In accordance with ASC 606, the Company performs an assessment of each contract to identify the performance obligations, determine the overall transaction price for the contract, allocate the transaction price to the performance obligations, and recognize the revenue when the performance obligations are satisfied. The Company utilizes the residual approach by which it estimates the standalone selling price by reference to the total transaction price less the sum of the observable standalone selling prices of other goods or services promised in the contract. The software license revenue is typically recognized at a point in time when control is transferred to the client, which is defined as the point in time when the client can use and benefit from the license. The software license is delivered before related services are provided and is functional without services, updates, or technical support. Related professional services include training and support services in which the standalone selling price is determined based on an input measure of hours incurred to total estimated hours and is recognized over time, usually which is the life of the contract. To determine the proper revenue recognition method for contracts, the Company evaluates whether two or more contracts should be combined and accounted for as one single contract and whether the combined contract should be accounted for as one performance obligation. With respect to the Company’s contracts, it is rare that multiple contracts should be combined into a single performance obligation. This evaluation requires significant judgment and the decision to combine a group of contracts or separate a single contract into multiple performance obligations could change the amount of revenue and profit recorded in a given period. Contracts are considered to have a single performance obligation if the promise to transfer the individual goods or services is not separately identifiable from other promises in the contracts, which is mainly because the Company provides a significant service of integrating a complex set of tasks and components into a single project or capability. The Company may enter into contracts that include separate phases or elements. If each phase or element is negotiated separately based on the technical resources required and/or the supply and demand for the services being provided, the Company evaluates if the contracts should be segmented. If certain criteria are met, the contracts would be segmented which could result in revenues being assigned to the different elements or phases with different rates of profitability based on the relative value of each element or phase to the estimated total contract revenue. Segmented contracts may comprise up to approximately 2.0% to 3.0% of the Company’s consolidated contract revenue. Contracts that cover multiple phases or elements of the project or service lifecycle (development, construction and maintenance and support) may be considered to have multiple performance obligations even when they are part of a single contract. For contracts with multiple performance obligations, the Company allocates the transaction price to each performance obligation using the best estimate of the standalone selling price of each distinct good or service in the contract. For the periods presented, the value of the separate performance obligations under contracts with multiple performance obligations (generally measurement and verification tasks under certain energy performance contracts) were not material. In cases where the Company does not provide the distinct good or service on a standalone basis, the primary method used to estimate standalone selling price is the expected cost plus a margin approach, under which the Company forecasts the Company’s expected costs of satisfying a performance obligation and then adds an appropriate margin for the distinct good or service. The Company provides quality of workmanship warranties to customers that are included in the sale and are not priced or sold separately or do not provide customers with a service in addition to assurance of compliance with agreed-upon specifications and industry standards. The Company does not consider these types of warranties to be separate performance obligations. In some cases, the Company has a master service or blanket agreement with a customer under which each task order releases the Company to perform specific portions of the overall scope in the service contract. Each task order is typically accounted for as a separate contract because the task order establishes the enforceable rights and obligations, and payment terms. Under ASC 606, variable consideration should be considered when determining the transaction price and estimates should be made for the variable consideration component of the transaction price, as well as assessing whether an estimate of variable consideration is constrained. For certain of the Company’s contracts, variable consideration can arise from modifications to the scope of services resulting from unapproved change orders or customer claims. Variable consideration is included in the transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is resolved. The Company estimates of variable consideration and determination of whether to include estimated amounts in the transaction price are based largely on assessments of legal enforceability, the Company’s performance, and all information (historical, current and forecasted) that is reasonably available to the Company. Due to the nature of the work required to be performed on many of the Company’s performance obligations, the estimation of total revenue and cost at completion is complex, subject to many variables and requires significant judgment. As a significant change in one or more of these estimates could affect the profitability of the Company’s contracts, the Company reviews and updates the Company’s contract-related estimates regularly through a company-wide disciplined project review process in which management reviews the progress and execution of the Company’s performance obligations and the estimate at completion (EAC). As part of this process, management reviews information including, but not limited to, any outstanding key contract matters, progress towards completion and the related program schedule and the related changes in estimates of revenues and costs. Management must make assumptions and estimates regarding labor productivity and availability, the complexity of the work to be performed, the cost and availability of materials, the performance of subcontractors, and the availability and timing of funding from the customer, among other variables. The Company recognizes adjustments in estimated profit on contracts under the cumulative catch-up method. Under this method, the impact of the adjustment on profit recorded to date is recognized in the period the adjustment is identified. Revenue and profit in future periods of contract performance is recognized using the adjusted estimate. If at any time the estimate of contract profitability indicates an anticipated loss on the contract, the Company recognizes the full amount of estimated loss in the period it is identified. Contracts are often modified to account for changes in contract specifications and requirements. The Company considers contract modifications to exist when the modification either creates new rights or obligations or changes the existing enforceable rights or obligations. Most of the Company’s contract modifications are for goods or services that are not distinct from existing contracts due to the significant integration provided in the context of the contract and are accounted for as if they were part of the original contract. The effect of a contract modification that is not distinct from the existing contract on the transaction price and the Company’s measure of progress for the performance obligation to which it relates is recognized as an adjustment to revenue (either as an increase in or a reduction of revenue) on a cumulative catch-up basis. For contract modifications that result in the promise to deliver goods or services that are distinct from the existing contract and the increase in price of the contract is for the same amount as the standalone selling price of the additional goods or services included in the modification, the Company accounts for such contract modifications as a separate contract. The Company includes claims to vendors, subcontractors and others as a receivable and a reduction in recognized costs when enforceability of the claim is established by the contract and the amounts are reasonably estimable and probable of being recovered. The amounts are recorded up to the extent of the lesser of the amounts management expects to recover or to costs incurred. Billing practices are governed by the contract terms of each project based upon costs incurred, achievement of milestones or pre-agreed schedules. Billings do not necessarily correlate with revenue recognized using the percentage-of-completion method of revenue recognition. Direct costs of contract revenue consist primarily of that portion of technical and nontechnical salaries and wages that has been incurred in connection with revenue producing projects. Direct costs of contract revenue also include production expenses, subcontractor services and other expenses that are incurred in connection with revenue producing projects. Direct costs of contract revenue exclude that portion of technical and nontechnical salaries and wages related to marketing efforts, vacations, holidays and other time not spent directly generating revenue under existing contracts. Such costs are included in general and administrative expenses. Additionally, payroll taxes, bonuses and employee benefit costs for all Company personnel are included in general and administrative expenses in the accompanying consolidated statements of comprehensive income since no allocation of these costs is made to direct costs of contract revenue. No allocation of facilities costs is made to direct costs of contract revenue. Other companies may classify as direct costs of contract revenue some of the costs that the Company classifies as general and administrative costs. The Company expenses direct costs of contract revenue when incurred. Included in revenue and costs are all reimbursable costs for which the Company has the risk or on which the fee was based at the time of bid or negotiation. No revenue or cost is recorded for costs in which the Company acts solely in the capacity of an agent and has no risks associated with such costs. Accounts receivable are carried at original invoice amount less an estimate made for doubtful accounts based upon a review of all outstanding amounts on a quarterly basis. Management determines allowances for doubtful accounts through specific identification of amounts considered to be uncollectible and potential write-offs, plus a non-specific allowance for other amounts for which some potential loss has been determined to be probable based on current and past experience. The Company’s historical credit losses have been minimal with governmental entities and large public utilities, but disputes may arise related to these receivable amounts. Accounts receivable are written off when deemed uncollectible. Recoveries of accounts receivable previously written off are recorded when received. Retainage, included in contract assets, represents amounts withheld from billings to the Company’s clients pursuant to provisions in the contracts and may not be paid to the Company until specific tasks are completed or the project is completed and, in some instances, for even longer periods. As of October 1, 2021 and January 1, 2021, contract assets included retainage of approximately $4.9 million and $6.2 million, respectively.

REVENUES (Tables)

REVENUES (Tables)	9 Months Ended
	Oct. 01, 2021
REVENUES
Schedule of Contracts by Reportable Segments and Type of Contracts	​ Segment Contract Type Revenue Recognition Method ​ Time-and-materials Time-and-materials Energy Unit-based Unit-based ​ Software license Unit-based ​ Fixed price Percentage-of-completion ​ Time-and-materials Time-and-materials Engineering and Consulting Unit-based Unit-based ​ Fixed price Percentage-of-completion

SUPPLEMENTAL FINANCIAL STATEM_2

SUPPLEMENTAL FINANCIAL STATEMENT DATA (Tables)	9 Months Ended
	Oct. 01, 2021
SUPPLEMENTAL FINANCIAL STATEMENT DATA
Schedule of equipment and leasehold improvements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 1, ​ January 1, ​ 2021 2021 ​ ​ (in thousands) Furniture and fixtures ​ $ 4,070 ​ $ 4,088 Computer hardware and software ​ 22,838 ​ 18,047 Leasehold improvements ​ 3,008 ​ 2,994 Equipment under finance leases ​ 3,084 ​ 2,370 Automobiles, trucks, and field equipment ​ 3,106 ​ 3,216 Subtotal ​ 36,106 ​ 30,715 Accumulated depreciation and amortization ​ (21,746) ​ (18,209) Equipment and leasehold improvements, net ​ $ 14,360 ​ $ 12,506
Schedule of accrued liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 1, ​ January 1, ​ 2021 2021 ​ ​ (in thousands) Accrued subcontractor costs ​ $ 21,495 ​ $ 19,124 Other ​ 10,965 ​ 11,981 Accrued bonuses ​ ​ 7,852 ​ ​ 5,211 Compensation and payroll taxes ​ 3,224 ​ 1,983 Employee withholdings ​ 3,140 ​ 2,768 Paid leave bank ​ 509 ​ 687 Total accrued liabilities ​ $ 47,185 ​ $ 41,754
Schedule of changes in the carrying value of goodwill by reporting unit	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ January 1, ​ Additional ​ Additions / ​ October 1, ​ 2021 Purchase Cost Adjustments 2021 ​ ​ (in thousands) Reporting Unit: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Energy ​ $ 129,375 ​ $ — ​ $ — ​ $ 129,375 Engineering and Consulting ​ ​ 749 ​ ​ — ​ ​ — ​ ​ 749 ​ ​ $ 130,124 ​ $ — ​ $ — ​ $ 130,124
Schedule of gross amounts and accumulated amortization of the Company's acquired identifiable intangible assets with finite useful lives	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 1, 2021 ​ January 1, 2021 ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ Accumulated ​ Gross ​ Accumulated ​ Amortization ​ Amount Amortization Amount Amortization Period ​ ​ (in thousands) ​ (in years) Finite: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Backlog ​ $ 7,944 ​ $ 6,978 ​ $ 7,944 ​ $ 6,249 ​ 1.0 Tradename ​ 15,911 ​ 8,494 ​ 15,911 ​ 6,984 2.5 ​ - ​ 6.0 Non-compete agreements ​ ​ 1,420 ​ ​ 1,407 ​ ​ 1,420 ​ ​ 1,390 ​ 4.0 ​ - ​ 5.0 Developed technology ​ ​ 15,500 ​ ​ 8,240 ​ ​ 15,500 ​ ​ 6,107 ​ 8.0 Customer relationships ​ ​ 58,149 ​ ​ 18,516 ​ ​ 58,149 ​ ​ 14,248 ​ 5.0 ​ - ​ 8.0 Total finite intangible assets ​ ​ 98,924 ​ $ 43,635 ​ ​ 98,924 ​ $ 34,978 ​ ​ ​ ​ ​ ​ In-process research and technology (1) ​ ​ 310 ​ ​ — ​ ​ 310 ​ ​ — ​ ​ ​ ​ ​ ​ Total intangible assets ​ $ 99,234 ​ $ 43,635 ​ $ 99,234 ​ $ 34,978 ​ ​ ​ ​ ​ ​ (1) In-process research and technology will not be amortized until put into use.

DERIVATIVE FINANCIAL INSTRUME_2

DERIVATIVE FINANCIAL INSTRUMENTS (Tables)	9 Months Ended
	Oct. 01, 2021
DERIVATIVE FINANCIAL INSTRUMENTS
Schedule of fair values of outstanding derivatives designated as hedging instruments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Fair Value of Derivative ​ ​ Instruments as of ​ ​ Balance Sheet Location ​ October 1, 2021 ​ January 1, 2021 ​ ​ ​ ​ (in thousands) Interest rate swap agreement ​ Accrued liabilities ​ $ (201) ​ $ (624) Interest rate swap agreement ​ Other noncurrent (liabilities) assets ​ $ — ​ $ (48)
Schedule of accumulated other comprehensive income (loss)	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Gain (Loss) on ​ Accumulated Other ​ Derivative Instruments Comprehensive Loss ​ ​ (in thousands) Balances at January 1, 2021 ​ $ (488) ​ $ (488) Other comprehensive loss before reclassifications ​ ​ 163 ​ ​ 163 Amounts reclassified from accumulated other comprehensive income: ​ ​ 0 ​ ​ 0 Income tax benefit (expense) related to derivative instruments ​ ​ (35) ​ ​ (35) Net current-period other comprehensive loss ​ ​ 128 ​ ​ 128 Balances at April 2, 2021 ​ $ (360) ​ $ (360) Other comprehensive loss before reclassifications ​ ​ 156 ​ ​ 156 Amounts reclassified from accumulated other comprehensive income: ​ ​ 0 ​ ​ 0 Income tax benefit (expense) related to derivative instruments ​ ​ (52) ​ ​ (52) Net current-period other comprehensive loss ​ ​ 104 ​ ​ 104 Balances at July 2, 2021 ​ $ (256) ​ $ (256) Other comprehensive loss before reclassifications ​ ​ 152 ​ ​ 152 Amounts reclassified from accumulated other comprehensive income: ​ ​ 0 ​ ​ 0 Income tax benefit (expense) related to derivative instruments ​ ​ (41) ​ ​ (41) Net current-period other comprehensive loss ​ ​ 111 ​ ​ 110 Balances at October 1, 2021 ​ $ (145) ​ $ (145)

DEBT OBLIGATIONS (Tables)

DEBT OBLIGATIONS (Tables)	9 Months Ended
	Oct. 01, 2021
DEBT OBLIGATIONS
Schedule of debt obligations, excluding obligations under capital leases	​ ​ ​ ​ ​ ​ ​ ​ ​ October 1, January 1, ​ ​ 2021 ​ 2021 ​ ​ (in thousands) Outstanding borrowings on Term A Loan ​ $ 77,500 ​ $ 85,000 Outstanding borrowings on Revolving Credit Facility ​ ​ — ​ ​ — Outstanding borrowings on Delayed Draw Term Loan ​ ​ 24,750 ​ ​ 27,000 Other debt agreements ​ ​ 478 ​ ​ 1,996 Total debt ​ ​ 102,728 ​ ​ 113,996 Issuance costs and debt discounts ​ ​ (646) ​ ​ (822) Subtotal ​ ​ 102,082 ​ ​ 113,174 Less current portion of long-term debt ​ 13,336 ​ 14,996 Long-term debt portion ​ $ 88,746 ​ $ 98,178

LEASES (Tables)

LEASES (Tables)	9 Months Ended
	Oct. 01, 2021
LEASES
Summary of the Lease Expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Nine Months Ended ​ October 1, ​ October 2, ​ October 1, ​ October 2, ​ 2021 2020 2021 2020 ​ (in thousands) ​ (in thousands) Operating lease cost $ 1,596 ​ $ 1,761 ​ $ 4,941 ​ $ 5,269 Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of assets ​ 139 ​ ​ 146 ​ ​ 397 ​ ​ 456 Interest on lease liabilities ​ 9 ​ ​ 6 ​ ​ 22 ​ ​ 23 Total net lease cost $ 1,744 ​ $ 1,913 ​ $ 5,360 ​ $ 5,748
Summary of Lease Information Presented on the Condensed Consolidated Balance Sheet	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ October 1, January 1, ​ ​ ​ 2021 ​ 2021 ​ ​ ​ (in thousands) ​ Operating leases: ​ ​ ​ ​ ​ ​ ​ Right-of-use assets ​ $ 16,096 ​ $ 20,130 ​ ​ ​ ​ ​ ​ ​ Lease liability ​ $ 5,472 ​ $ 5,844 ​ Lease liability, less current portion ​ 11,842 ​ 15,649 ​ Total lease liabilities ​ $ 17,314 ​ $ 21,493 ​ ​ ​ ​ ​ ​ ​ Finance leases (included in equipment and leasehold improvements, net): ​ ​ ​ ​ ​ ​ ​ Equipment and leasehold improvements, net ​ $ 3,084 ​ $ 2,370 ​ Accumulated depreciation ​ (1,954) ​ (1,826) ​ Total equipment and leasehold improvements, net ​ $ 1,130 ​ $ 544 ​ ​ ​ ​ ​ ​ ​ ​ Finance lease obligations ​ $ 372 ​ $ 248 ​ Finance lease obligations, less current portion ​ ​ 659 ​ ​ 236 ​ Total finance lease obligations ​ $ 1,031 ​ $ 484 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average remaining lease term (in years): ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ 3.96 ​ ​ 4.40 ​ Finance Leases ​ ​ 2.63 ​ ​ 2.02 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average discount rate: ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ 4.34 % ​ 4.44 % Finance Leases ​ ​ 2.97 % ​ 3.74 %
Summary of Other Information and Supplemental Cash Flow Information Related to Finance and Operating Leases	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine Months Ended ​ ​ October 1, ​ October 2, ​ ​ 2021 2020 ​ ​ (in thousands) Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ ​ Operating cash flow from operating leases ​ $ 5,115 ​ $ 5,162 Operating cash flow from finance leases ​ ​ 22 ​ ​ 23 Financing cash flow from finance leases ​ ​ 440 ​ ​ 435 ​ ​ ​ ​ ​ ​ ​ Right-of-use assets obtained in exchange for lease liabilities: ​ ​ ​ ​ ​ ​ Operating leases ​ $ 326 ​ $ 3,007
Summary of the Maturities of Operating Lease Liabilities	The following is a summary of the maturities of lease liabilities as of October 1, 2021: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Finance ​ ​ (in thousands) ​ Fiscal year: ​ ​ ​ ​ ​ ​ ​ Remainder of 2021 ​ $ 1,511 ​ $ 99 ​ 2022 ​ 5,701 ​ 400 ​ 2023 ​ 4,254 ​ ​ 357 ​ 2024 ​ ​ 2,772 ​ ​ 166 ​ 2025 ​ ​ 2,129 ​ 38 ​ 2026 and thereafter ​ 2,484 ​ 14 ​ Total lease payments ​ $ 18,851 ​ $ 1,074 ​ Less: Imputed interest ​ (1,537) ​ ​ (43) ​ Total lease obligations ​ 17,314 ​ ​ 1,031 ​ Less: Current obligations ​ 5,472 ​ ​ 372 ​ Noncurrent lease obligations ​ $ 11,842 ​ $ 659 ​
Summary of the Maturities of Finance Lease Liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Finance ​ ​ (in thousands) ​ Fiscal year: ​ ​ ​ ​ ​ ​ ​ Remainder of 2021 ​ $ 1,511 ​ $ 99 ​ 2022 ​ 5,701 ​ 400 ​ 2023 ​ 4,254 ​ ​ 357 ​ 2024 ​ ​ 2,772 ​ ​ 166 ​ 2025 ​ ​ 2,129 ​ 38 ​ 2026 and thereafter ​ 2,484 ​ 14 ​ Total lease payments ​ $ 18,851 ​ $ 1,074 ​ Less: Imputed interest ​ (1,537) ​ ​ (43) ​ Total lease obligations ​ 17,314 ​ ​ 1,031 ​ Less: Current obligations ​ 5,472 ​ ​ 372 ​ Noncurrent lease obligations ​ $ 11,842 ​ $ 659 ​

SEGMENT AND GEOGRAPHICAL INFO_2

SEGMENT AND GEOGRAPHICAL INFORMATION (Tables)	9 Months Ended
	Oct. 01, 2021
SEGMENT AND GEOGRAPHICAL INFORMATION
Schedule of financial information with respect to the reportable segments	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Engineering ​ Unallocated ​ ​ ​ ​ Consolidated ​ Energy & Consulting Corporate Intersegment Total ​ ​ (in thousands) Fiscal Three Months Ended October 1, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 81,523 ​ $ 16,774 ​ $ - ​ $ - ​ $ 98,297 Depreciation and amortization ​ ​ 4,023 ​ ​ 244 ​ ​ - ​ ​ - ​ ​ 4,267 Interest expense, net ​ ​ - ​ ​ - ​ ​ 937 ​ ​ - ​ ​ 937 Segment profit (loss) before income tax expense ​ ​ 2,138 ​ ​ 2,673 ​ ​ (4,207) ​ ​ - ​ ​ 604 Income tax expense (benefit) ​ ​ 610 ​ ​ 1,286 ​ ​ (2,132) ​ ​ - ​ ​ (236) Net income (loss) ​ ​ 1,529 ​ ​ 1,387 ​ ​ (2,076) ​ ​ - ​ ​ 840 Segment assets (1) ​ ​ 331,573 ​ ​ 23,134 ​ ​ 55,329 ​ ​ (23,130) ​ ​ 386,906 Fiscal Three Months Ended October 2, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 87,888 ​ $ 16,620 ​ $ - ​ $ - ​ $ 104,508 Depreciation and amortization ​ ​ 4,072 ​ ​ 267 ​ ​ - ​ ​ - ​ ​ 4,339 Interest expense, net ​ ​ 7 ​ ​ - ​ ​ 1,206 ​ ​ - ​ ​ 1,213 Segment profit (loss) before income tax expense ​ ​ 3,203 ​ ​ 2,757 ​ ​ (4,906) ​ ​ - ​ ​ 1,054 Income tax expense (benefit) ​ ​ (437) ​ ​ 1,300 ​ ​ (2,449) ​ ​ - ​ ​ (1,586) Net income (loss) ​ ​ 3,641 ​ ​ 1,457 ​ ​ (2,458) ​ ​ - ​ ​ 2,640 Segment assets (1) ​ ​ 348,350 ​ ​ 22,755 ​ ​ 50,481 ​ ​ (23,130) ​ ​ 398,456 Fiscal Nine Months Ended October 1, 2021 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 209,977 ​ $ 51,560 ​ $ - ​ $ - ​ $ 261,537 Depreciation and amortization ​ ​ 11,934 ​ ​ 744 ​ ​ - ​ ​ - ​ ​ 12,678 Interest expense, net ​ ​ 5 ​ ​ - ​ ​ 3,095 ​ ​ - ​ ​ 3,100 Segment profit (loss) before income tax expense ​ ​ (5,607) ​ ​ 7,507 ​ ​ (14,784) ​ ​ - ​ ​ (12,884) Income tax expense (benefit) ​ ​ (2,331) ​ ​ 3,122 ​ ​ (6,148) ​ ​ - ​ ​ (5,357) Net income (loss) ​ ​ (3,275) ​ ​ 4,386 ​ ​ (8,638) ​ ​ - ​ ​ (7,527) Segment assets (1) ​ ​ 331,573 ​ ​ 23,134 ​ ​ 55,329 ​ ​ (23,130) ​ ​ 386,906 Fiscal Nine Months Ended October 2, 2020 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 242,394 ​ $ 51,689 ​ $ - ​ $ - ​ $ 294,083 Depreciation and amortization ​ ​ 13,499 ​ ​ 825 ​ ​ - ​ ​ - ​ ​ 14,324 Interest expense, net ​ ​ 26 ​ ​ - ​ ​ 3,957 ​ ​ - ​ ​ 3,983 Segment profit (loss) before income tax expense ​ ​ (6,490) ​ ​ 7,953 ​ ​ (15,243) ​ ​ - ​ ​ (13,780) Income tax expense (benefit) ​ ​ (1,545) ​ ​ 1,894 ​ ​ (3,630) ​ ​ - ​ ​ (3,281) Net income (loss) ​ ​ (4,944) ​ ​ 6,059 ​ ​ (11,614) ​ ​ - ​ ​ (10,499) Segment assets (1) ​ ​ 348,350 ​ ​ 22,755 ​ ​ 50,481 ​ ​ (23,130) ​ ​ 398,456 (1) Segment assets are presented net of intercompany receivables.
Schedule of disaggregation of revenue	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended October 1, 2021 ​ Energy Engineering and Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 9,104 ​ $ 13,160 ​ $ 22,264 Unit-based ​ ​ 51,470 ​ ​ 2,650 ​ ​ 54,120 Fixed price ​ ​ 20,950 ​ ​ 963 ​ ​ 21,913 Total (1) ​ $ 81,524 ​ $ 16,773 ​ $ 98,297 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 7,741 ​ $ 1,568 ​ $ 9,309 Government ​ ​ 18,537 ​ ​ 15,181 ​ ​ 33,718 Utilities (2) ​ ​ 55,245 ​ ​ 24 ​ ​ 55,269 Total (1) ​ $ 81,524 ​ $ 16,773 ​ $ 98,297 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 81,524 ​ $ 16,773 ​ $ 98,297 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended October 1, 2021 ​ Energy Engineering and Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 25,060 ​ $ 40,444 ​ $ 65,504 Unit-based ​ ​ 132,688 ​ ​ 7,817 ​ ​ 140,505 Fixed price ​ ​ 52,229 ​ ​ 3,299 ​ ​ 55,528 Total (1) ​ $ 209,977 ​ $ 51,560 ​ $ 261,537 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 20,685 ​ $ 4,037 ​ $ 24,723 Government ​ ​ 45,766 ​ ​ 47,391 ​ ​ 93,157 Utilities (2) ​ ​ 143,525 ​ ​ 132 ​ ​ 143,657 Total (1) ​ $ 209,977 ​ $ 51,560 ​ $ 261,537 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 209,977 ​ $ 51,560 ​ $ 261,537 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended October 2, 2020 ​ Energy Engineering and Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 10,936 ​ $ 13,719 ​ $ 24,655 Unit-based ​ ​ 43,010 ​ ​ 2,082 ​ ​ 45,092 Fixed price ​ ​ 33,941 ​ ​ 820 ​ ​ 34,761 Total (1) ​ $ 87,887 ​ $ 16,621 ​ $ 104,508 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 10,737 ​ $ 1,300 ​ $ 12,037 Government ​ ​ 30,627 ​ ​ 14,657 ​ ​ 45,284 Utilities (2) ​ ​ 46,523 ​ ​ 664 ​ ​ 47,187 Total (1) ​ $ 87,887 ​ $ 16,621 ​ $ 104,508 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 87,887 ​ $ 16,621 ​ $ 104,508 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Nine months ended October 2, 2020 ​ Energy Engineering and Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 37,072 ​ $ 41,499 ​ $ 78,571 Unit-based ​ ​ 122,800 ​ ​ 7,180 ​ ​ 129,979 Fixed price ​ ​ 82,522 ​ ​ 3,011 ​ ​ 85,531 Total (1) ​ $ 242,394 ​ $ 51,689 ​ $ 294,083 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 28,355 ​ $ 3,978 ​ $ 32,333 Government ​ ​ 74,056 ​ ​ 46,390 ​ ​ 120,446 Utilities (2) ​ ​ 139,983 ​ ​ 1,321 ​ ​ 141,304 Total (1) ​ $ 242,394 ​ $ 51,689 ​ $ 294,083 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 242,394 ​ $ 51,689 ​ $ 294,083 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ (1) Amounts may not add to the totals due to rounding. (2) Includes the portion of revenue related to small business programs paid by the end user/customer. (3) Revenue from the Company’s foreign operations were not material for the three and nine months ended October 1, 2021 and October 2, 2020.

EARNINGS PER SHARE (EPS) (Table

EARNINGS PER SHARE (EPS) (Tables)	9 Months Ended
	Oct. 01, 2021
EARNINGS PER SHARE (EPS)
Schedule of number of weighted-average common shares outstanding used to compute basic and diluted EPS	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ Nine months ended ​ ​ October 1, ​ October 2, ​ October 1, ​ October 2, ​ 2021 2020 2021 2020 ​ ​ (in thousands, except per share amounts) Net income (loss) ​ $ 840 ​ $ 2,640 ​ $ (7,527) ​ $ (10,499) Weighted-average common shares outstanding ​ 12,606 ​ 11,992 ​ 12,391 ​ 11,723 Effect of dilutive stock options and restricted stock awards ​ 535 ​ 425 ​ — ​ — Weighted-average common shares outstanding-diluted ​ 13,141 ​ 12,417 ​ 12,391 ​ 11,723 Earnings (Loss) per share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic ​ $ 0.07 ​ $ 0.22 ​ $ (0.61) ​ $ (0.90) Diluted ​ $ 0.06 ​ $ 0.21 ​ $ (0.61) ​ $ (0.90)

ORGANIZATION AND OPERATIONS O_3

ORGANIZATION AND OPERATIONS OF THE COMPANY (Details) $ in Millions

Nov. 03, 2021contract

Dec. 31, 2021

Oct. 01, 2021USD ($)

Jul. 02, 2021

Apr. 02, 2021

Jan. 01, 2021

Oct. 02, 2020

Jul. 03, 2020

Apr. 03, 2020

Oct. 01, 2021USD ($)segment

Dec. 31, 2021

Jan. 01, 2021

Dec. 27, 2019

Summary of Significant Accounting Policies [Line Items]

Number of reporting segments | segment

2

Length of fiscal period

91 days

91 days

91 days

91 days

91 days

91 days

91 days

98 days

364 days

371 days

Revolving Credit Facility

Summary of Significant Accounting Policies [Line Items]

Amount of new contracts | $

$ 781

$ 781

Subsequent Event

Summary of Significant Accounting Policies [Line Items]

Number of contracts cancelled | contract

0

Direct Install Programs Serving Small Business

Summary of Significant Accounting Policies [Line Items]

Percentage of gross revenues (as a percent)

40.00%

Other Programs

Summary of Significant Accounting Policies [Line Items]

Percentage of gross revenues (as a percent)

60.00%

Minimum

Summary of Significant Accounting Policies [Line Items]

Length of fiscal period

91 days

364 days

Maximum

Summary of Significant Accounting Policies [Line Items]

Length of fiscal period

98 days

371 days

REVENUES (Details)

REVENUES (Details)	3 Months Ended		9 Months Ended
	Oct. 01, 2021USD ($)	Oct. 02, 2020USD ($)	Oct. 01, 2021USD ($)segment	Oct. 02, 2020USD ($)	Jan. 01, 2021USD ($)
Disaggregation of Revenue [Line Items]
Number of reporting segments | segment			2
Payroll taxes, bonuses and employee benefit costs for all Company personnel	$ 19,374,000	$ 17,530,000	$ 57,530,000	$ 53,273,000
Revenue of the entity recorded in which it acts solely in the capacity of an agent			0
Accounts receivable
Disaggregation of Revenue [Line Items]
Retained accounts receivable	$ 4,900,000		$ 4,900,000		$ 6,200,000
Maximum
Disaggregation of Revenue [Line Items]
Percent of revenue (as a percent)	3.00%		3.00%
Minimum
Disaggregation of Revenue [Line Items]
Percent of revenue (as a percent)	2.00%		2.00%
Cost of Sales
Disaggregation of Revenue [Line Items]
Payroll taxes, bonuses and employee benefit costs for all Company personnel			$ 0
Allocation of facilities costs to contract revenue			$ 0

SUPPLEMENTAL FINANCIAL STATEM_3

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Accounts Receivable (Details) - USD ($) $ in Millions	9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items]
Cash proceeds from sale of trade receivables	$ 8	$ 0
Other, net
Accounts, Notes, Loans and Financing Receivable [Line Items]
Discount on trade accounts receivable sold	$ 0.8

SUPPLEMENTAL FINANCIAL STATEM_4

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Equipment and Leasehold Improvements, Net (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020	Jan. 01, 2021
EQUIPMENT AND LEASEHOLD IMPROVEMENTS
Equipment and leasehold improvements, net	$ 36,106		$ 36,106		$ 30,715
Accumulated depreciation and amortization	(21,746)		(21,746)		(18,209)
Total equipment and leasehold improvements, net	14,360		14,360		12,506
Amortization of assets	139	$ 146	397	$ 456
Furniture and fixtures
EQUIPMENT AND LEASEHOLD IMPROVEMENTS
Equipment and leasehold improvements, net	4,070		4,070		4,088
Computer hardware and software
EQUIPMENT AND LEASEHOLD IMPROVEMENTS
Equipment and leasehold improvements, net	22,838		22,838		18,047
Leasehold improvements
EQUIPMENT AND LEASEHOLD IMPROVEMENTS
Equipment and leasehold improvements, net	3,008		3,008		2,994
Equipment under Finance Lease
EQUIPMENT AND LEASEHOLD IMPROVEMENTS
Equipment and leasehold improvements, net	3,084		3,084		2,370
Accumulated depreciation and amortization	(1,954)		(1,954)		(1,826)
Total equipment and leasehold improvements, net	1,130		1,130		544
Amortization of assets			400		600
Automobiles, trucks, and field equipment
EQUIPMENT AND LEASEHOLD IMPROVEMENTS
Equipment and leasehold improvements, net	$ 3,106		$ 3,106		$ 3,216

SUPPLEMENTAL FINANCIAL STATEM_5

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Accrued Liabilities (Details) - USD ($) $ in Thousands	Oct. 01, 2021	Jan. 01, 2021
ACCRUED LIABILITIES
Accrued subcontractor costs	$ 21,495	$ 19,124
Other	10,965	11,981
Accrued bonuses	7,852	5,211
Compensation and payroll taxes	3,224	1,983
Employee withholdings	3,140	2,768
Paid leave bank	509	687
Total accrued liabilities	$ 47,185	$ 41,754

SUPPLEMENTAL FINANCIAL STATEM_6

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Goodwill (Details) $ in Thousands	Oct. 01, 2021USD ($)
Changes in carrying value of goodwill
Goodwill at beginning of period	$ 130,124
Goodwill at end of period	130,124
Energy
Changes in carrying value of goodwill
Goodwill at beginning of period	129,375
Goodwill at end of period	129,375
Engineering and Consulting
Changes in carrying value of goodwill
Goodwill at beginning of period	749
Goodwill at end of period	$ 749

SUPPLEMENTAL FINANCIAL STATEM_7

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Intangible Assets (Details) - USD ($) $ in Thousands	9 Months Ended
	Oct. 01, 2021	Jan. 01, 2021
Goodwill and other intangible assets
Total finite intangible assets, Gross Amount	$ 98,924	$ 98,924
In-process research and technology, Gross Amount	310	310
Accumulated Amortization	43,635	34,978
Total intangible assets	99,234	99,234
Backlog
Goodwill and other intangible assets
Total finite intangible assets, Gross Amount	7,944	7,944
Accumulated Amortization	$ 6,978	6,249
Amortization Period (in years)	1 year
Tradename
Goodwill and other intangible assets
Total finite intangible assets, Gross Amount	$ 15,911	15,911
Accumulated Amortization	$ 8,494	6,984
Tradename | Minimum
Goodwill and other intangible assets
Amortization Period (in years)	2 years 6 months
Tradename | Maximum
Goodwill and other intangible assets
Amortization Period (in years)	6 years
Non-compete agreements
Goodwill and other intangible assets
Total finite intangible assets, Gross Amount	$ 1,420	1,420
Accumulated Amortization	$ 1,407	1,390
Non-compete agreements | Minimum
Goodwill and other intangible assets
Amortization Period (in years)	4 years
Non-compete agreements | Maximum
Goodwill and other intangible assets
Amortization Period (in years)	5 years
Developed technology
Goodwill and other intangible assets
Total finite intangible assets, Gross Amount	$ 15,500	15,500
Accumulated Amortization	$ 8,240	6,107
Amortization Period (in years)	8 years
Customer relationships
Goodwill and other intangible assets
Total finite intangible assets, Gross Amount	$ 58,149	58,149
Accumulated Amortization	$ 18,516	$ 14,248
Customer relationships | Minimum
Goodwill and other intangible assets
Amortization Period (in years)	5 years
Customer relationships | Maximum
Goodwill and other intangible assets
Amortization Period (in years)	8 years

DERIVATIVE FINANCIAL INSTRUME_3

DERIVATIVE FINANCIAL INSTRUMENTS (Details) - Interest swap agreement - Cash flow hedge - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Oct. 01, 2021	Jul. 01, 2022	Jan. 31, 2019
Derivative [Line Items]
Notional amount			$ 35
Fixed rate (in percent)			2.47%
Effective portion of interest rate swap designated as cash flow hedge before tax effect	$ 0.5
Accumulated other comprehensive income to interest expense	$ 0
Forecast
Derivative [Line Items]
Accumulated other comprehensive income to interest expense		$ (0.2)

DERIVATIVE FINANCIAL INSTRUME_4

DERIVATIVE FINANCIAL INSTRUMENTS - Fair Values (Details) - Designated as hedging instruments - Interest swap agreement - USD ($) $ in Thousands	Oct. 01, 2021	Jan. 01, 2021
Accrued liabilities.
Derivatives, Fair Value [Line Items]
Fair value of Derivative Instruments	$ (201)	$ (624)
Other noncurrent (liabilities) assets
Derivatives, Fair Value [Line Items]
Fair value of Derivative Instruments		$ (48)

DERIVATIVE FINANCIAL INSTRUME_5

DERIVATIVE FINANCIAL INSTRUMENTS - Others (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020
Cash flow hedge
Derivative [Line Items]
Effective portion	$ 0.1	$ 0.2	$ 0.3	$ 0.2
Fair Value Hedging
Derivative [Line Items]
Effective portion	$ 0.1	$ 0.2	$ 0.3	$ 0.2

DERIVATIVE FINANCIAL INSTRUME_6

DERIVATIVE FINANCIAL INSTRUMENTS - Accumulated Balances and Reporting Period Activities (Details) - USD ($) $ in Thousands	3 Months Ended
	Oct. 01, 2021	Jul. 02, 2021	Apr. 02, 2021
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Balances	$ 170,813	$ 171,631	$ 169,164
Balances	177,614	170,813	171,631
Gain (Loss) on Derivative Instruments
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Balances	(256)	(360)	(488)
Other comprehensive loss before reclassifications	152	156	163
Income tax benefit (expense) related to derivative instruments	(41)	(52)	(35)
Net current-period other comprehensive loss	111	104	128
Balances	(145)	(256)	(360)
Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Balances	(256)	(360)	(488)
Other comprehensive loss before reclassifications	152	156	163
Income tax benefit (expense) related to derivative instruments	(41)	(52)	(35)
Net current-period other comprehensive loss	110	104	128
Balances	$ (145)	$ (256)	$ (360)

DEBT OBLIGATIONS (Details)

DEBT OBLIGATIONS (Details) - USD ($) $ in Thousands	Oct. 01, 2021	Jan. 01, 2021
Debt Obligations
Total debt	$ 102,728	$ 113,996
Issuance costs and debt discounts	(646)	(822)
Total debt maturities	102,082	113,174
Less current portion of long-term debt	(13,336)	(14,996)
Long-term debt portion	88,746	98,178
Term A Loan
Debt Obligations
Total debt	77,500	85,000
Delayed Draw Term Loan Facility
Debt Obligations
Total debt	24,750	27,000
Other debt agreements
Debt Obligations
Total debt	$ 478	$ 1,996

DEBT OBLIGATIONS - Line of Cred

DEBT OBLIGATIONS - Line of Credit (Details) $ in Millions	Dec. 31, 2020	Oct. 01, 2021	Jul. 02, 2021USD ($)	Jun. 26, 2019USD ($)
2019 Credit Agreement
Debt Instrument [Line Items]
Minimum fixed charge coverage ratio		1.20
2019 Credit Agreement | Debt Covenant Threshold Tranche One
Debt Instrument [Line Items]
Maximum total leverage ratio	3.50
2019 Credit Agreement | Debt Covenant Threshold Tranche Two
Debt Instrument [Line Items]
Maximum total leverage ratio	3.25
Term A Loan | BMO
Debt Instrument [Line Items]
Amount borrowed to finance acquisition				$ 100
Delayed Draw Term Loan Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				50
Amount available for borrowing			$ 0
Revolving Credit Facility
Debt Instrument [Line Items]
Maximum borrowing capacity				$ 50

DEBT OBLIGATIONS - Debt Agreeme

DEBT OBLIGATIONS - Debt Agreements (Details) - USD ($) $ in Millions	Apr. 30, 2021	Apr. 29, 2021	May 06, 2020	May 05, 2020	Jul. 02, 2021
Third Amendment
Debt Instrument [Line Items]
Maximum capital expenditure, debt covenant					$ 7
Minimum liquidity					5
Maximum aggregate amount of earn-out payments during Relief Period		$ 7			$ 7
Fourth Amendment
Debt Instrument [Line Items]
Maximum capital expenditure, debt covenant	$ 15
Minimum liquidity	10
Maximum aggregate amount of earn-out payments during Relief Period	$ 17
London Interbank Offered Rate One Month LIBOR | Third Amendment | Debt Interest Period One [Member]
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)				2.00%
Federal Funds Effective Swap Rate | Third Amendment | Debt Interest Period Three [Member]
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)			0.50%
Base rate | London Interbank Offered Rate One Month LIBOR | Third Amendment | Debt Interest Period Two [Member]
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)			2.50%
LIBOR | London Interbank Offered Rate One Month LIBOR | Third Amendment | Debt Interest Period Three [Member]
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)			1.00%
Minimum | Letters of Credit
Debt Instrument [Line Items]
Commitment fee (as a percent)	0.84%		0.84%
Minimum | Delayed Draw Term Loan And Revolving Credit Facility
Debt Instrument [Line Items]
Commitment fee (as a percent)	0.15%
Minimum | Delayed Draw Term Loan And Revolving Credit Facility | Debt Interest Period Three [Member]
Debt Instrument [Line Items]
Commitment fee (as a percent)			0.15%
Minimum | LIBOR | Fourth Amendment
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)	1.125%
Interest rate	0.00%
Minimum | London Interbank Offered Rate One Month LIBOR | Third Amendment | Debt Interest Period Three [Member]
Debt Instrument [Line Items]
Interest rate			0.75%
Minimum | Base rate | Fourth Amendment
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)	0.125%
Minimum | Base rate | London Interbank Offered Rate One Month LIBOR | Third Amendment | Debt Interest Period Three [Member]
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)			0.125%
Minimum | LIBOR | London Interbank Offered Rate One Month LIBOR | Third Amendment | Debt Interest Period Three [Member]
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)			1.125%
Maximum | Letters of Credit
Debt Instrument [Line Items]
Commitment fee (as a percent)	1.688%		2.50%
Maximum | Delayed Draw Term Loan And Revolving Credit Facility
Debt Instrument [Line Items]
Commitment fee (as a percent)	0.40%
Maximum | Delayed Draw Term Loan And Revolving Credit Facility | Debt Interest Period Three [Member]
Debt Instrument [Line Items]
Commitment fee (as a percent)			0.45%
Maximum | LIBOR | Fourth Amendment
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)	2.25%
Maximum | Base rate | Fourth Amendment
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)	1.25%
Maximum | Base rate | London Interbank Offered Rate One Month LIBOR | Third Amendment | Debt Interest Period Three [Member]
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)			1.50%
Maximum | LIBOR | London Interbank Offered Rate One Month LIBOR | Third Amendment | Debt Interest Period Three [Member]
Debt Instrument [Line Items]
Spread on floating interest rate (as a percent)			2.50%

LEASES - Change in Accounting P

LEASES - Change in Accounting Policy (Details) $ in Thousands	9 Months Ended
	Oct. 01, 2021USD ($)
Leases
Operating lease, option to extend	true
Operating lease, option to terminate	true
Residual value guarantee	$ 0
Minimum
Leases
Operating lease, remaining lease term	1 year
Maximum
Leases
Operating lease, remaining lease term	8 years
Operating lease, extension term	5 years
Operating lease, terminate term	1 year

LEASES - Lease Expense (Details

LEASES - Lease Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020
Lease cost
Operating lease cost	$ 1,596	$ 1,761	$ 4,941	$ 5,269
Amortization of assets	139	146	397	456
Interest on lease liabilities	9	6	22	23
Total net lease cost	$ 1,744	$ 1,913	$ 5,360	$ 5,748

LEASES - Impact of Adoption (De

LEASES - Impact of Adoption (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020	Jan. 01, 2021
Operating leases:
Right-of-use assets	$ 16,096		$ 16,096		$ 20,130
Lease liability	5,472		5,472		5,844
Lease liability, less current portion	11,842		11,842		15,649
Total lease obligations	17,314		17,314		21,493
Finance leases (included in equipment and leasehold improvements, net):
Equipment and leasehold improvements, net	36,106		36,106		30,715
Accumulated depreciation	21,746		21,746		18,209
Total equipment and leasehold improvements, net	14,360		14,360		12,506
Finance lease obligations	372		372		248
Finance lease obligations, less current portion	659		659		236
Total lease obligations	$ 1,031		$ 1,031		$ 484
Operating Leases, remaining lease term	3 years 11 months 15 days		3 years 11 months 15 days		4 years 4 months 24 days
Finance Leases, remaining lease term	2 years 7 months 17 days		2 years 7 months 17 days		2 years 7 days
Operating Leases, discount rate	4.34%		4.34%		4.44%
Finance Leases, discount rate	2.97%		2.97%		3.74%
Rent expenses	$ 1,600	$ 1,900	$ 5,200	$ 5,700
Equipment under Finance Lease
Finance leases (included in equipment and leasehold improvements, net):
Equipment and leasehold improvements, net	3,084		3,084		$ 2,370
Accumulated depreciation	1,954		1,954		1,826
Total equipment and leasehold improvements, net	$ 1,130		$ 1,130		$ 544

LEASES - Supplemental Cash Flow

LEASES - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flow from operating leases			$ 5,115	$ 5,162
Operating cash flow from finance leases			22	23
Financing cash flow from finance leases			440	435
Right-of-use assets obtained in exchange for lease liabilities for operating leases			326	3,007
Operating lease cost	$ 1,596	$ 1,761	$ 4,941	$ 5,269

LEASES - Maturities of Lease Li

LEASES - Maturities of Lease Liabilities (Details) - USD ($) $ in Thousands	Oct. 01, 2021	Jan. 01, 2021
Operating
Remainder of 2021	$ 1,511
2022	5,701
2023	4,254
2024	2,772
2025	2,129
2026 and thereafter	2,484
Total lease payments	18,851
Less: Imputed interest	(1,537)
Total lease obligations	17,314	$ 21,493
Less: Current obligations	5,472	5,844
Noncurrent lease obligations	11,842	15,649
Finance
Remainder of 2021	99
2022	400
2023	357
2024	166
2025	38
2026 and thereafter	14
Total lease payments	1,074
Less: Imputed interest	(43)
Total lease obligations	1,031	484
Less: Current obligations	372	248
Noncurrent lease obligations	$ 659	$ 236

COMMITMENTS AND VARIABLE INTE_2

COMMITMENTS AND VARIABLE INTEREST ENTITIES - Employee Benefit Plans (Details) $ in Millions	9 Months Ended
	Oct. 01, 2021USD ($)item	Oct. 02, 2020USD ($)
COMMITMENTS AND VARIABLE INTEREST ENTITIES
Number of VIE | item	1
Employee Benefit Plans
Maximum employee contribution as a percentage of compensation under 401 (k) Plan	50.00%
Service period (in months)	3 months
Attained age (in years)	21 years
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	6.00%
Employer matching contributions | $	$ 1.6	$ 0.9

SEGMENT AND GEOGRAPHICAL INFO_3

SEGMENT AND GEOGRAPHICAL INFORMATION (Details) $ in Thousands	3 Months Ended						6 Months Ended		9 Months Ended
	Oct. 01, 2021USD ($)	Jul. 02, 2021USD ($)	Apr. 02, 2021USD ($)	Oct. 02, 2020USD ($)	Jul. 03, 2020USD ($)	Apr. 03, 2020USD ($)	Jul. 02, 2021USD ($)	Jul. 03, 2020USD ($)	Oct. 01, 2021USD ($)segment	Oct. 02, 2020USD ($)	Jan. 01, 2021USD ($)
SEGMENT INFORMATION
Number of reporting segments | segment									2
Segment reconciliation
Contract revenue	$ 98,297			$ 104,508					$ 261,537	$ 294,083
Depreciation and amortization	4,267			4,339					12,678	14,324
Interest expense	937			1,213					3,100	3,983
Segment profit (loss) before income tax expense	604			1,054					(12,884)	(13,780)
Income tax (benefit) expense	(236)			(1,586)					(5,357)	(3,281)
Net income (loss)	840	$ (4,601)	$ (3,766)	2,640	$ (4,985)	$ (8,154)			(7,527)	(10,499)
Segment assets(1)	386,906			398,456					386,906	398,456	$ 410,323
Energy
Segment reconciliation
Contract revenue	81,524			87,887					209,977	242,394
Engineering and Consulting
Segment reconciliation
Contract revenue	16,773			16,621					51,560	51,689
Reporting Segments | Energy
Segment reconciliation
Contract revenue	81,523			87,888					209,977	242,394
Depreciation and amortization	4,023			4,072					11,934	13,499
Interest expense				7					5	26
Segment profit (loss) before income tax expense	2,138			3,203					(5,607)	(6,490)
Income tax (benefit) expense	610			(437)					(2,331)	(1,545)
Net income (loss)	1,529			3,641					(3,275)	(4,944)
Segment assets(1)	331,573			348,350					331,573	348,350
Reporting Segments | Engineering and Consulting
Segment reconciliation
Contract revenue	16,774			16,620					51,560	51,689
Depreciation and amortization	244			267					744	825
Segment profit (loss) before income tax expense	2,673			2,757					7,507	7,953
Income tax (benefit) expense	1,286			1,300					3,122	1,894
Net income (loss)	1,387			1,457					4,386	6,059
Segment assets(1)	23,134			22,755					23,134	22,755
Unallocated Corporate
Segment reconciliation
Interest expense	937			1,206					3,095	3,957
Segment profit (loss) before income tax expense	(4,207)			(4,906)					(14,784)	(15,243)
Income tax (benefit) expense	(2,132)			(2,449)					(6,148)	(3,630)
Net income (loss)	(2,076)			(2,458)					(8,638)	(11,614)
Segment assets(1)	55,329			50,481					55,329	50,481
Intersegment
Segment reconciliation
Contract revenue		$ 0			$ 0		$ 0	$ 0
Segment assets(1)	$ (23,130)			$ (23,130)					$ (23,130)	$ (23,130)

SEGMENT AND GEOGRAPHICAL INFO_4

SEGMENT AND GEOGRAPHICAL INFORMATION - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020
Disaggregation of Revenue [Line Items]
Revenue	$ 98,297	$ 104,508	$ 261,537	$ 294,083
Domestic
Disaggregation of Revenue [Line Items]
Revenue	98,297	104,508	261,537	294,083
Energy
Disaggregation of Revenue [Line Items]
Revenue	81,524	87,887	209,977	242,394
Energy | Domestic
Disaggregation of Revenue [Line Items]
Revenue	81,524	87,887	209,977	242,394
Engineering and Consulting
Disaggregation of Revenue [Line Items]
Revenue	16,773	16,621	51,560	51,689
Engineering and Consulting | Domestic
Disaggregation of Revenue [Line Items]
Revenue	16,773	16,621	51,560	51,689
Commercial
Disaggregation of Revenue [Line Items]
Revenue	9,309	12,037	24,723	32,333
Commercial | Energy
Disaggregation of Revenue [Line Items]
Revenue	7,741	10,737	20,685	28,355
Commercial | Engineering and Consulting
Disaggregation of Revenue [Line Items]
Revenue	1,568	1,300	4,037	3,978
Government
Disaggregation of Revenue [Line Items]
Revenue	33,718	45,284	93,157	120,446
Government | Energy
Disaggregation of Revenue [Line Items]
Revenue	18,537	30,627	45,766	74,056
Government | Engineering and Consulting
Disaggregation of Revenue [Line Items]
Revenue	15,181	14,657	47,391	46,390
Utilities
Disaggregation of Revenue [Line Items]
Revenue	55,269	47,187	143,657	141,304
Utilities | Energy
Disaggregation of Revenue [Line Items]
Revenue	55,245	46,523	143,525	139,983
Utilities | Engineering and Consulting
Disaggregation of Revenue [Line Items]
Revenue	24	664	132	1,321
Time-and-materials
Disaggregation of Revenue [Line Items]
Revenue	22,264	24,655	65,504	78,571
Time-and-materials | Energy
Disaggregation of Revenue [Line Items]
Revenue	9,104	10,936	25,060	37,072
Time-and-materials | Engineering and Consulting
Disaggregation of Revenue [Line Items]
Revenue	13,160	13,719	40,444	41,499
Unit-based
Disaggregation of Revenue [Line Items]
Revenue	54,120	45,092	140,505	129,979
Unit-based | Energy
Disaggregation of Revenue [Line Items]
Revenue	51,470	43,010	132,688	122,800
Unit-based | Engineering and Consulting
Disaggregation of Revenue [Line Items]
Revenue	2,650	2,082	7,817	7,180
Fixed price
Disaggregation of Revenue [Line Items]
Revenue	21,913	34,761	55,528	85,531
Fixed price | Energy
Disaggregation of Revenue [Line Items]
Revenue	20,950	33,941	52,229	82,522
Fixed price | Engineering and Consulting
Disaggregation of Revenue [Line Items]
Revenue	$ 963	$ 820	$ 3,299	$ 3,011

SEGMENT AND GEOGRAPHICAL INFO_5

SEGMENT AND GEOGRAPHICAL INFORMATION - Concentration risk (Details)	3 Months Ended		9 Months Ended
	Oct. 01, 2021customerstate	Oct. 02, 2020USD ($)customer	Oct. 01, 2021USD ($)statecustomer	Oct. 02, 2020USD ($)customer
Concentration Risk [Line Items]
Number of States in which Entity Operates | state	24		24
Customer Concentration Risk | Revenue from Contract with Customer Benchmark | CALIFORNIA
Concentration Risk [Line Items]
Customer concentration risk percentage	38.90%	32.30%	36.20%	40.20%
Customer Concentration Risk | Revenue from Contract with Customer Benchmark | NEW YORK
Concentration Risk [Line Items]
Customer concentration risk percentage	19.00%	19.20%	20.70%	18.40%
Top Ten Customers | Customer Concentration Risk | Revenue from Contract with Customer Benchmark
Concentration Risk [Line Items]
Number of customers | customer	10	10	10	10
Customer concentration risk percentage	52.40%	46.70%	46.80%	48.60%
Los Angeles Department Of Water And Power | Customer Concentration Risk | Revenue from Contract with Customer Benchmark
Concentration Risk [Line Items]
Number of customers	1			1
Customer concentration risk percentage	17.00%			12.80%
Los Angeles Department Of Water And Power | Customer Concentration Risk | Revenue from Contract with Customer Benchmark | Energy Segment
Concentration Risk [Line Items]
Number of customers | customer	1
Customer concentration risk percentage	20.40%
Los Angeles Department of Water and Power And The Dormitory Authority State Of New York | Customer Concentration Risk | Revenue from Contract with Customer Benchmark | Energy Segment
Concentration Risk [Line Items]
Number of customers				2
Customer concentration risk percentage				26.80%
City Of Elk Grove | Customer Concentration Risk | Revenue from Contract with Customer Benchmark | Engineering And Consulting Segment
Concentration Risk [Line Items]
Number of customers		1	1	1
Customer concentration risk percentage		18.70%	12.20%	19.60%
Consolidated Edison Of New York And The Los Angeles Department Of Water And Power | Customer Concentration Risk | Revenue from Contract with Customer Benchmark | Energy Segment
Concentration Risk [Line Items]
Number of customers			2
Customer concentration risk percentage			21.50%

INCOME TAXES - Provision (Detai

INCOME TAXES - Provision (Details) - USD ($)	3 Months Ended		9 Months Ended
	Oct. 01, 2021	Oct. 02, 2020	Oct. 01, 2021	Oct. 02, 2020	Dec. 28, 2018
INCOME TAXES
Valuation reserve related to California net operating losses					$ 86,000
Valuation allowance change			$ 0
Liability for uncertain tax positions	$ 0		0
Income Tax Expense (Benefit)	(236,000)	$ (1,586,000)	$ (5,357,000)	$ (3,281,000)
Tax expense (benefit) related to net operating loss carryback provisions	$ (700,000)

EARNINGS PER SHARE (EPS) (Detai

EARNINGS PER SHARE (EPS) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Oct. 01, 2021	Jul. 02, 2021	Apr. 02, 2021	Oct. 02, 2020	Jul. 03, 2020	Apr. 03, 2020	Oct. 01, 2021	Oct. 02, 2020
Earnings (Loss) per share:
Net income (loss)	$ 840	$ (4,601)	$ (3,766)	$ 2,640	$ (4,985)	$ (8,154)	$ (7,527)	$ (10,499)
Weighted-average common shares outstanding (in shares)	12,606			11,992			12,391	11,723
Effect of dilutive stock options and restricted stock awards (in shares)	535			425
Weighted-average common shares outstanding-diluted (in shares)	13,141			12,417			12,391	11,723
Earnings (Loss) per share:
Basic	$ 0.07			$ 0.22			$ (0.61)	$ (0.90)
Diluted	$ 0.06			$ 0.21			$ (0.61)	$ (0.90)