Willdan (WLDN) 10-Q 3 Aug 23 2023 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2023	Aug. 02, 2023
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Document Period End Date	Jun. 30, 2023
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		13,594,982
Current Fiscal Year End Date	--12-29
Document Fiscal Period Focus	Q2
Document Fiscal Year Focus	2023
Entity Central Index Key	0001370450
Amendment Flag	false

CONDENSED CONSOLIDATED BALANCE

CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022
Current assets:
Cash and cash equivalents	$ 13,649	$ 8,806
Restricted cash		10,679
Accounts receivable, net of allowance for doubtful accounts of $373 and $640 at June 30, 2023 and December 30, 2022, respectively	54,572	60,202
Contract assets	79,300	83,060
Other receivables	2,852	4,773
Prepaid expenses and other current assets	5,399	6,454
Total current assets	155,772	173,974
Equipment and leasehold improvements, net	25,494	22,537
Goodwill	130,124	130,124
Right-of-use assets	13,894	12,390
Other intangible assets, net	36,237	41,486
Other assets	15,607	10,620
Deferred income taxes, net	17,692	18,543
Total assets	394,820	409,674
Current liabilities:
Accounts payable	35,155	28,833
Accrued liabilities	36,954	59,110
Contingent consideration payable		4,000
Contract liabilities	14,950	12,585
Notes payable	102,619	16,903
Finance lease obligations	1,143	1,113
Lease liability	4,877	4,625
Total current liabilities	195,698	127,169
Notes payable	19	90,544
Finance lease obligations, less current portion	1,251	1,601
Lease liability, less current portion	10,731	8,599
Other noncurrent liabilities	259	259
Total liabilities	207,958	228,172
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; 13,504 and 13,296 shares issued and outstanding at June 30, 2023 and December 30, 2022, respectively	135	133
Additional paid-in capital	181,747	177,718
Retained earnings	4,980	3,651
Total stockholders' equity	186,862	181,502
Total liabilities and stockholders' equity	$ 394,820	$ 409,674

CONDENSED CONSOLIDATED BALANC_2

CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022
Accounts receivable, allowance for doubtful accounts
Accounts receivable, allowance for doubtful accounts	$ 373	$ 640
Preferred stock
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	10,000,000	10,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	40,000,000	40,000,000
Common stock, shares issued (in shares)	13,504,000	13,296,000
Common stock, shares outstanding (in shares)	13,504,000	13,296,000

CONDENSED CONSOLIDATED STATEMEN

CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jul. 01, 2022	Jun. 30, 2023	Jul. 01, 2022
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Contract revenue	$ 119,077	$ 102,645	$ 221,680	$ 194,483
Direct costs of contract revenue (inclusive of directly related depreciation and amortization):
Salaries and wages	21,302	21,284	41,712	40,094
Subcontractor services and other direct costs	57,142	49,771	98,054	91,439
Total direct costs of contract revenue	78,444	71,055	139,766	131,533
General and administrative expenses:
Salaries and wages, payroll taxes and employee benefits	22,416	20,439	44,801	39,796
Facilities and facility related	2,619	2,373	4,897	4,771
Stock-based compensation	1,287	1,714	2,820	5,019
Depreciation and amortization	4,128	4,426	8,328	8,835
Other	7,709	7,936	14,580	15,435
Total general and administrative expenses	38,159	36,888	75,426	73,856
Income (Loss) from operations	2,474	(5,298)	6,488	(10,906)
Other income (expense):
Interest expense, net	(2,207)	(1,030)	(4,673)	(1,781)
Other, net	373	329	513	526
Total other expense, net	(1,834)	(701)	(4,160)	(1,255)
Income (Loss) before income taxes	640	(5,999)	2,328	(12,161)
Income tax (benefit) expense	243	(1,673)	999	(4,062)
Net income (loss)	397	(4,326)	1,329	(8,099)
Other comprehensive income (loss):
Unrealized gain (loss) on derivative contracts, net of tax				38
Comprehensive income (loss)	$ 397	$ (4,326)	$ 1,329	$ (8,061)
Earnings (Loss) per share:
Basic (in dollars per share)	$ 0.03	$ (0.33)	$ 0.10	$ (0.63)
Diluted (in dollars per share)	$ 0.03	$ (0.33)	$ 0.10	$ (0.63)
Weighted-average shares outstanding:
Basic (in shares)	13,344	13,016	13,305	12,901
Diluted (in shares)	13,487	13,016	13,481	12,901

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
Balance at Dec. 31, 2021	$ 128	$ 167,032	$ (38)	$ 12,099	$ 179,221
Balance (in shares) at Dec. 31, 2021	12,804
Increase (Decrease) in Stockholders' Equity
Shares of common stock issued in connection with employee stock purchase plan	$ 1	1,560			1,561
Shares of common stock issued in connection with employee stock purchase plan (in shares)	52
Shares of common stock issued in connection with incentive stock plan		23			23
Shares of common stock issued in connection with incentive stock plan (in shares)	4
Shares used to pay taxes on stock grants		(837)			(837)
Shares used to pay taxes on stock grants (in shares)	(27)
Issuance of restricted stock award and units	$ 3	(3)
Issuance of restricted stock award and units (in shares)	373
Stock-based compensation expense		3,305			3,305
Net Income (Loss)				(3,773)	(3,773)
Net unrealized gain on derivative contracts			38		38
Balance at Apr. 01, 2022	$ 132	171,080		8,326	179,538
Balance (in shares) at Apr. 01, 2022	13,206
Balance at Dec. 31, 2021	$ 128	167,032	$ (38)	12,099	179,221
Balance (in shares) at Dec. 31, 2021	12,804
Increase (Decrease) in Stockholders' Equity
Net Income (Loss)					(8,099)
Balance at Jul. 01, 2022	$ 132	172,678		4,000	176,810
Balance (in shares) at Jul. 01, 2022	13,215
Balance at Apr. 01, 2022	$ 132	171,080		8,326	179,538
Balance (in shares) at Apr. 01, 2022	13,206
Increase (Decrease) in Stockholders' Equity
Shares used to pay taxes on stock grants		(116)			(116)
Shares used to pay taxes on stock grants (in shares)	(5)
Issuance of restricted stock award and units (in shares)	14
Stock-based compensation expense		1,714			1,714
Net Income (Loss)				(4,326)	(4,326)
Balance at Jul. 01, 2022	$ 132	172,678		4,000	176,810
Balance (in shares) at Jul. 01, 2022	13,215
Balance at Dec. 30, 2022	$ 133	177,718		3,651	$ 181,502
Balance (in shares) at Dec. 30, 2022	13,296				13,296
Increase (Decrease) in Stockholders' Equity
Shares of common stock issued in connection with employee stock purchase plan	$ 1	1,391			$ 1,392
Shares of common stock issued in connection with employee stock purchase plan (in shares)	92
Shares used to pay taxes on stock grants		(124)			(124)
Shares used to pay taxes on stock grants (in shares)	(7)
Issuance of restricted stock award and units	$ 1	(1)
Issuance of restricted stock award and units (in shares)	108
Stock-based compensation expense		1,533			1,533
Net Income (Loss)				932	932
Balance at Mar. 31, 2023	$ 135	180,517		4,583	185,235
Balance (in shares) at Mar. 31, 2023	13,489
Balance at Dec. 30, 2022	$ 133	177,718		3,651	$ 181,502
Balance (in shares) at Dec. 30, 2022	13,296				13,296
Increase (Decrease) in Stockholders' Equity
Net Income (Loss)					$ 1,329
Balance at Jun. 30, 2023	$ 135	181,747		4,980	$ 186,862
Balance (in shares) at Jun. 30, 2023	13,504				13,504
Balance at Mar. 31, 2023	$ 135	180,517		4,583	$ 185,235
Balance (in shares) at Mar. 31, 2023	13,489
Increase (Decrease) in Stockholders' Equity
Shares of common stock issued in connection with incentive stock plan		7			7
Shares of common stock issued in connection with incentive stock plan (in shares)	2
Shares used to pay taxes on stock grants		(64)			(64)
Shares used to pay taxes on stock grants (in shares)	(4)
Issuance of restricted stock award and units (in shares)	17
Stock-based compensation expense		1,287			1,287
Net Income (Loss)				397	397
Balance at Jun. 30, 2023	$ 135	$ 181,747		$ 4,980	$ 186,862
Balance (in shares) at Jun. 30, 2023	13,504				13,504

CONDENSED CONSOLIDATED STATEM_3

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jul. 01, 2022
Cash flows from operating activities:
Net income (loss)	$ 1,329	$ (8,099)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Depreciation and amortization	8,328	8,835
Deferred income taxes, net	851	(2,842)
(Gain) loss on sale/disposal of equipment	(50)	(69)
Provision for doubtful accounts	146	107
Stock-based compensation	2,820	5,019
Accretion and fair value adjustments of contingent consideration		111
Changes in operating assets and liabilities, net of effects from business acquisitions:
Accounts receivable	5,484	6,803
Contract assets	3,760	(1,889)
Other receivables	1,921	36
Prepaid expenses and other current assets	1,217	225
Other assets	(4,987)	(48)
Accounts payable	6,322	(8,859)
Accrued liabilities	(11,477)	(648)
Contract liabilities	2,365	(2,089)
Right-of-use assets	880	(162)
Net cash (used in) provided by operating activities	18,909	(3,569)
Cash flows from investing activities:
Purchase of equipment, software, and leasehold improvements	(5,762)	(4,344)
Proceeds from sale of equipment	55	73
Net cash (used in) provided by investing activities	(5,707)	(4,271)
Cash flows from financing activities:
Payments on contingent consideration	(4,000)	(10,206)
Payment on restricted cash	(10,679)
Payments on notes payable	(971)	(1,051)
Borrowings under term loan facility and line of credit	5,000	20,000
Repayments under term loan facility and line of credit	(9,000)	(6,500)
Principal payments on finance leases	(599)	(444)
Proceeds from stock option exercise	7	23
Proceeds from sales of common stock under employee stock purchase plan	1,392	1,561
Cash used to pay taxes on stock grants	(188)	(953)
Net cash (used in) provided by financing activities	(19,038)	2,430
Net increase (decrease) in cash, cash equivalents and restricted cash	(5,836)	(5,410)
Cash, cash equivalents and restricted cash at beginning of period	19,485	11,221
Cash, cash equivalents and restricted cash at end of period	13,649	5,811
Cash paid (received) during the period for:
Interest	4,464	1,584
Income taxes	(1,696)	474
Supplemental disclosures of noncash investing and financing activities:
Equipment acquired under finance leases	$ 278	$ 1,431

ORGANIZATION AND OPERATIONS OF

ORGANIZATION AND OPERATIONS OF THE COMPANY	6 Months Ended
	Jun. 30, 2023
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 resource and infrastructure needs undergo continuous change, the Company helps organizations and their communities evolve and thrive by providing a wide range of technical services for energy solutions, greenhouse gas reduction, 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 for our clients. 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 2023, which ends on December 29, 2023, will be comprised of 52 weeks, with all quarters consisting of 13 weeks each. Fiscal year 2022, which ended on December 30, 2022, was comprised of 52 weeks, with all 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. Credit Agreement Refinancing As described in Note 5, “ Debt Obligations Quantitative and Qualitative Disclosures About Market Risk In accordance with ASC Topic 205, when preparing financial statements for each reporting period, the Company evaluates whether there are conditions or events that, when considered in the aggregate, raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the financial statements are issued. The Company considered its Credit Agreement’s principal and interest payment due on June 26, 2024 and assessed its current financial condition and liquidity sources, including current funds available, forecasted future cash flows, and conditional and unconditional obligations due over the next twelve months. Based on that analysis, only as a result of the Company’s obligation under the Credit Agreement to make final payment of all then remaining principal and interest on June 26, 2024, does an event arise which raises substantial doubt with respect to the Company's ability to continue as a going concern within one year after the date that the Condensed Consolidated Financial Statements are issued. The Company intends to refinance its Credit Agreement and has entered into an engagement to secure a new three-year financing facility with a syndicate of financial institutions as lenders which, among other things, will repay 100% of the obligations under the existing Credit Agreement and extend the due date of the maturity payment by more than two years from the current maturity date. The Company expects to finalize its refinancing efforts and enter into a new credit facility during the second half of fiscal 2023. Accordingly, the Company believes that its refinancing plan alleviates any substantial doubt about the Company's ability to continue as a going concern within one year after the date that the consolidated financial statements are issued because it expects to fully refinance the Credit Agreement with a new credit facility prior to June 26, 2024, the date on which final payment of all then remaining principal and interest under the current Credit Agreement is due. ​ ​

RECENT ACCOUNTING PRONOUNCEMENT

RECENT ACCOUNTING PRONOUNCEMENTS	6 Months Ended
	Jun. 30, 2023
RECENT ACCOUNTING PRONOUNCEMENTS
RECENT ACCOUNTING PRONOUNCEMENTS	2. RECENT ACCOUNTING PRONOUNCEMENTS As of June 30, 2023, there were no accounting pronouncements recently issued, or with future effective dates, that are either applicable nor are expected to have an impact to the Company’s Condensed Consolidated Financial Statements. ​

REVENUES

REVENUES	6 Months Ended
	Jun. 30, 2023
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 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 June 30, 2023 and December 30, 2022, contract assets included retainage of approximately $12.5 million and $8.5 million, respectively. ​

SUPPLEMENTAL FINANCIAL STATEMEN

SUPPLEMENTAL FINANCIAL STATEMENT DATA	6 Months Ended
	Jun. 30, 2023
SUPPLEMENTAL FINANCIAL STATEMENT DATA
SUPPLEMENTAL FINANCIAL STATEMENT DATA	4. SUPPLEMENTAL FINANCIAL STATEMENT DATA Restricted Cash The following table provides a reconciliation of cash and cash equivalents, and restricted cash reported within the condensed consolidated balance sheets to the total cash, cash equivalents, and restricted cash shown in the consolidated statements of cash flows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 30, ​ 2023 2022 ​ ​ (in thousands) Cash and cash equivalents ​ $ 13,649 ​ $ 8,806 Restricted cash ​ — ​ 10,679 Total cash, cash equivalents, and restricted cash shown in the consolidated statement of cash flows ​ $ 13,649 ​ $ 19,485 ​ Under certain utility contracts, the Company periodically receives cash deposits to be held in trust for the payment of energy incentive rebates to be sent directly to the utility’s end-customer on behalf of the utility. The Company acts solely as the utility’s agent to distribute these funds to the end-customer and, accordingly, the Company classifies these contractually restricted funds as restricted cash. Because these funds are held in trust for pass through to the utility’s customers and have no impact on the Company’s working capital or operating cash flows, these cash receipts are presented in the consolidated statement of cash flows as financing cash inflows, “Receipt of restricted cash”, with the subsequent payments classified as financing cash outflows, “Payment of restricted cash.” Equipment and Leasehold Improvements ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 30, ​ 2023 2022 ​ ​ (in thousands) Furniture and fixtures ​ $ 4,188 ​ $ 4,062 Computer hardware and software ​ 40,434 ​ 35,635 Leasehold improvements ​ 3,832 ​ 3,097 Equipment under finance leases ​ 5,588 ​ 5,503 Automobiles, trucks, and field equipment ​ 3,135 ​ 3,134 Subtotal ​ 57,177 ​ 51,431 Accumulated depreciation and amortization ​ (31,683) ​ (28,894) Equipment and leasehold improvements, net ​ $ 25,494 ​ $ 22,537 ​ Included in accumulated depreciation and amortization is $0.6 million and $1.1 million of amortization expense related to equipment held under finance leases for the six months ended June 30, 2023 and for fiscal year 2022, respectively. Accrued Liabilities ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 30, ​ 2023 2022 ​ ​ (in thousands) Accrued subcontractor costs ​ $ 21,927 ​ $ 28,374 Accrued bonuses ​ ​ 6,758 ​ ​ 8,470 Employee withholdings ​ 2,795 ​ 2,571 Compensation and payroll taxes ​ 2,690 ​ 2,340 Rebate and other ​ ​ 303 ​ ​ 14,643 Accrued accounting and taxes ​ 2,481 ​ 2,712 Total accrued liabilities ​ $ 36,954 ​ $ 59,110 ​ Goodwill ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 30, ​ Additional ​ Additions / ​ June 30, ​ 2022 Purchase Cost Adjustments 2023 ​ ​ (in thousands) Reporting Unit: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Energy ​ $ 129,375 ​ $ — ​ $ — ​ $ 129,375 Engineering and Consulting ​ ​ 749 ​ ​ — ​ ​ — ​ ​ 749 ​ ​ $ 130,124 ​ $ — ​ $ — ​ $ 130,124 ​ ​ Intangible Assets ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2023 ​ December 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ Accumulated ​ Gross ​ Accumulated ​ Amortization ​ Amount Amortization Amount Amortization Period ​ ​ (in thousands) ​ (in years) Finite: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Tradename ​ $ 15,911 ​ $ 11,986 ​ $ 15,911 ​ $ 10,990 2.5 ​ - ​ 6.0 Developed technology ​ ​ 15,810 ​ ​ 13,332 ​ ​ 15,810 ​ ​ 11,871 ​ 8.0 Customer relationships ​ ​ 58,149 ​ ​ 28,315 ​ ​ 58,149 ​ ​ 25,523 ​ 5.0 ​ - ​ 8.0 Total intangible assets ​ $ 89,870 ​ $ 53,633 ​ $ 89,870 ​ $ 48,384 ​ ​ ​ ​ ​ ​

DEBT OBLIGATIONS

DEBT OBLIGATIONS	6 Months Ended
	Jun. 30, 2023
DEBT OBLIGATIONS
DEBT OBLIGATIONS	5. DEBT OBLIGATIONS Debt obligations, excluding obligations under finance leases (see Note 6, Leases, ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 30, ​ ​ 2023 ​ 2022 ​ ​ (in thousands) Outstanding borrowings on Term A Loan ​ $ 60,000 ​ $ 65,000 Outstanding borrowings on Revolving Credit Facility ​ ​ 5,000 ​ ​ — Outstanding borrowings on Delayed Draw Term Loan ​ ​ 37,000 ​ ​ 41,000 Other debt agreements ​ ​ 988 ​ ​ 1,958 Total debt ​ ​ 102,988 ​ ​ 107,958 Issuance costs and debt discounts ​ ​ (350) ​ ​ (511) Subtotal ​ ​ 102,638 ​ ​ 107,447 Less current portion of long-term debt ​ 102,619 ​ 16,903 Long-term debt portion ​ $ 19 ​ $ 90,544 ​ 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, the Third Amendment, dated as of May 6, 2020, the Fourth Amendment, dated April 30, 2021, the Fifth Amendment, dated March 8, 2022, the Sixth Amendment, dated August 2, 2022, and the Seventh Amendment, dated November 1, 2022, the “Credit Agreement”) with a syndicate of financial institutions as lenders and BMO Harris Bank, N.A., as administrative agent (the “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. Pursuant to the terms of the Seventh Amendment to the Credit Agreement (the “Seventh Amendment”), among other things, (A) aggregate borrowings under the Revolving Credit Facility were restricted to no more than $10.0 million at any time during the period from November 1, 2022 through the date on which financial statements and compliance documents were received by the Administrative Agent for the fiscal quarter ending March 31, 2023, and (B) access to the accordion feature of the Credit Agreement was limited to periods when the Company’s Total Leverage Ratio (as defined in the Credit Agreement) was less than 3.0. ​ On April 28, 2023, the Company delivered to the Administrative Agent the required financial statements and compliance documents for the fiscal quarter ending March 31, 2023, reflecting full compliance with the restrictive covenants under the Credit Agreement, and thus effectively terminating the limitations on borrowing capacity and other restrictions imposed under the terms set by the Seventh Amendment. ​ Effective April 28, 2023, borrowings under the Credit Agreement bear interest at either a Base Rate (as defined in the Credit Agreement) or the Secured Overnight Financing Rate (“SOFR”), at the Company’s option, and in each case, plus an applicable margin, which applicable margin ranges from 0.125% to 1.25% with respect to Base Rate borrowings and 1.125% to 2.25% with respect to SOFR borrowings, depending on the Total Leverage Ratio; provided, that SOFR cannot be less than 0.00%, with the specific pricing reset on each date on which the Administrative Agent receives the required financial statements under the Credit Agreement for the fiscal quarter then ended. The Company must also pay a commitment fee for the unused portion of the Revolving Credit Facility and the Delayed Draw Term Loan under the Credit Agreement, which ranges from 0.15% to 0.40% per annum depending on the Total 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 1.688% per annum, in each case, depending on whether such letter of credit is a performance or financial letter of credit and the Total Leverage Ratio. ​ The Credit Agreement requires the Company to comply with certain financial covenants, including requiring that the Company maintain a (i) Total Leverage Ratio of at least 3.25 to 1.00, and (ii) Fixed Charge Coverage Ratio (as defined in the Credit Agreement) of not less than 1.20 to 1.00, in each case tested quarterly. The Credit Agreement also contains customary events of default and contains other customary restrictive covenants. ​ As of June 30, 2023, the Company was in compliance with all covenants contained in the Credit Agreement. ​ 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	6 Months Ended
	Jun. 30, 2023
LEASES
LEASES	6. LEASES The Company leases certain office facilities under long-term, non-cancellable operating leases that expire at various dates through the year 2028. In addition, the Company is obligated under finance leases for certain furniture and office equipment that expire at various dates through the year 2027. From time to time, the Company enters into non-cancelable leases for some of its 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 typically 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 the Company is typically liable to the lessor for the remaining lease payments under the term of the lease. Additionally, all of the Company’s month-to-month leases are cancelable by the Company or the lessor, at any time, and are not included in the Company’s right-of-use asset or lease liability. As of June 30, 2023, 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 ​ Six Months Ended ​ June 30, ​ July 1, ​ June 30, ​ July 1, ​ 2023 2022 2023 2022 ​ (in thousands) ​ (in thousands) Operating lease cost $ 1,664 ​ $ 1,534 ​ $ 3,157 ​ $ 3,112 Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of assets ​ 318 ​ ​ 255 ​ ​ 629 ​ ​ 488 Interest on lease liabilities ​ 24 ​ ​ 15 ​ ​ 46 ​ ​ 29 Total net lease cost $ 2,006 ​ $ 1,804 ​ $ 3,832 ​ $ 3,629 ​ The following is a summary of lease information presented on the Company’s consolidated balance sheet: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 30, ​ ​ ​ 2023 ​ 2022 ​ ​ ​ (in thousands) ​ Operating leases: ​ ​ ​ ​ ​ ​ ​ Right-of-use assets ​ $ 13,894 ​ $ 12,390 ​ ​ ​ ​ ​ ​ ​ Lease liability ​ $ 4,877 ​ $ 4,625 ​ Lease liability, less current portion ​ 10,731 ​ 8,599 ​ Total lease liabilities ​ $ 15,608 ​ $ 13,224 ​ ​ ​ ​ ​ ​ ​ Finance leases (included in equipment and leasehold improvements, net): ​ ​ ​ ​ ​ ​ ​ Equipment and leasehold improvements, net ​ $ 5,588 ​ $ 5,503 ​ Accumulated depreciation ​ (3,266) ​ (2,830) ​ Total equipment and leasehold improvements, net ​ $ 2,322 ​ $ 2,673 ​ ​ ​ ​ ​ ​ ​ ​ Finance lease obligations ​ $ 1,143 ​ $ 1,113 ​ Finance lease obligations, less current portion ​ ​ 1,251 ​ ​ 1,601 ​ Total finance lease obligations ​ $ 2,394 ​ $ 2,714 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average remaining lease term (in years): ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ 3.60 ​ ​ 3.35 ​ Finance Leases ​ ​ 2.42 ​ ​ 2.66 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average discount rate: ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ 5.74 % ​ 4.25 % Finance Leases ​ ​ 4.06 % ​ 3.47 % ​ Rent expense was $1.8 million and $3.4 million for the three and six months ended June 30, 2023, respectively, as compared to $1.7 million and $3.3 million for the three and six months ended July 1, 2022, respectively. ​ ​ ​ The following is a summary of other information and supplemental cash flow information related to finance and operating leases: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended ​ ​ June 30, ​ July 1, ​ ​ 2023 2022 ​ ​ (in thousands) Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ ​ Operating cash flow from operating leases ​ $ 3,003 ​ $ 3,273 Operating cash flow from finance leases ​ ​ 46 ​ ​ 29 Financing cash flow from finance leases ​ ​ 599 ​ ​ 444 ​ ​ ​ ​ ​ ​ ​ Right-of-use assets obtained in exchange for lease liabilities: ​ ​ ​ ​ ​ ​ Operating leases ​ $ 4,264 ​ $ 1,002 ​ The following is a summary of the maturities of lease liabilities as of June 30, 2023: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Finance ​ ​ (in thousands) ​ Fiscal year: ​ ​ ​ ​ ​ ​ ​ Remainder of 2023 ​ $ 2,793 ​ $ 681 ​ 2024 ​ 4,968 ​ 1,071 ​ 2025 ​ 3,988 ​ ​ 472 ​ 2026 ​ ​ 3,369 ​ ​ 211 ​ 2027 ​ ​ 1,519 ​ 80 ​ 2028 and thereafter ​ 816 ​ 7 ​ Total lease payments ​ ​ 17,453 ​ ​ 2,522 ​ Less: Imputed interest ​ (1,845) ​ ​ (128) ​ Total lease obligations ​ 15,608 ​ ​ 2,394 ​ Less: Current obligations ​ 4,877 ​ ​ 1,143 ​ Noncurrent lease obligations ​ $ 10,731 ​ $ 1,251 ​ ​ 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	6 Months Ended
	Jun. 30, 2023
COMMITMENTS AND VARIABLE INTEREST ENTITIES
COMMITMENTS AND VARIABLE INTEREST ENTITIES	7. COMMITMENTS AND VARIABLE INTEREST ENTITIES Employee Benefit Plans The Company has a qualified profit sharing plan pursuant to Code Section 401(a) and qualified The Company’s defined contribution plan (the “Plan”) covers employees who have completed three months of service and who have attained 21 years of age. The Company elects to make matching contributions equal to 50% of the participants’ contributions to the Plan, up to 6% of the individual participant’s compensation, and subject to a maximum of $3,000 per employee. Under the Plan, the Company may make discretionary contributions to employee accounts. During each of the six months ended June 30, 2023 and July 1, 2022, the Company made matching contributions of $1.6 million. 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	6 Months Ended
	Jun. 30, 2023
SEGMENT AND GEOGRAPHICAL INFORMATION
SEGMENT AND GEOGRAPHICAL INFORMATION	8. 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 six months ended June 30, 2023 and July 1, 2022. 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 and reconciliation to the amounts reported in the Company’s Condensed Consolidated Financial Statements is as follows: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Engineering ​ Unallocated ​ ​ ​ ​ Consolidated ​ Energy & Consulting Corporate Intersegment Total ​ ​ (in thousands) Fiscal Three Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 98,015 ​ $ 21,062 ​ $ - ​ $ - ​ $ 119,077 Depreciation and amortization ​ ​ 3,877 ​ ​ 251 ​ ​ - ​ ​ - ​ ​ 4,128 Interest expense, net ​ ​ 1 ​ ​ - ​ ​ 2,206 ​ ​ - ​ ​ 2,207 Segment profit (loss) before income tax expense ​ ​ 603 ​ ​ 3,218 ​ ​ (3,181) ​ ​ - ​ ​ 640 Income tax expense (benefit) ​ ​ 207 ​ ​ 1,332 ​ ​ (1,296) ​ ​ - ​ ​ 243 Net income (loss) ​ ​ 397 ​ ​ 1,885 ​ ​ (1,885) ​ ​ - ​ ​ 397 Segment assets (1) ​ ​ 333,136 ​ ​ 23,851 ​ ​ 60,963 ​ ​ (23,130) ​ ​ 394,820 Fiscal Three Months Ended July 1, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 84,675 ​ $ 17,970 ​ $ - ​ $ - ​ $ 102,645 Depreciation and amortization ​ ​ 4,183 ​ ​ 243 ​ ​ - ​ ​ - ​ ​ 4,426 Interest expense, net ​ ​ 1 ​ ​ - ​ ​ 1,029 ​ ​ - ​ ​ 1,030 Segment profit (loss) before income tax expense ​ ​ (6,357) ​ ​ 2,531 ​ ​ (2,173) ​ ​ - ​ ​ (5,999) Income tax expense (benefit) ​ ​ (1,891) ​ ​ 732 ​ ​ (514) ​ ​ - ​ ​ (1,673) Net income (loss) ​ ​ (4,467) ​ ​ 1,798 ​ ​ (1,657) ​ ​ - ​ ​ (4,326) Segment assets (1) ​ ​ 323,070 ​ ​ 23,293 ​ ​ 58,650 ​ ​ (23,130) ​ ​ 381,883 Fiscal Six Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 181,300 ​ $ 40,380 ​ $ - ​ $ - ​ $ 221,680 Depreciation and amortization ​ ​ 7,801 ​ ​ 527 ​ ​ - ​ ​ - ​ ​ 8,328 Interest expense, net ​ ​ 3 ​ ​ - ​ ​ 4,670 ​ ​ - ​ ​ 4,673 Segment profit (loss) before income tax expense ​ ​ 3,374 ​ ​ 5,805 ​ ​ (6,851) ​ ​ - ​ ​ 2,328 Income tax expense (benefit) ​ ​ 1,448 ​ ​ 2,490 ​ ​ (2,939) ​ ​ - ​ ​ 999 Net income (loss) ​ ​ 1,927 ​ ​ 3,313 ​ ​ (3,911) ​ ​ - ​ ​ 1,329 Segment assets (1) ​ ​ 333,136 ​ ​ 23,851 ​ ​ 60,963 ​ ​ (23,130) ​ ​ 394,820 Fiscal Six Months Ended July 1, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 159,561 ​ $ 34,922 ​ $ - ​ $ - ​ $ 194,483 Depreciation and amortization ​ ​ 8,340 ​ ​ 495 ​ ​ - ​ ​ - ​ ​ 8,835 Interest expense, net ​ ​ 5 ​ ​ - ​ ​ 1,776 ​ ​ - ​ ​ 1,781 Segment profit (loss) before income tax expense ​ ​ (10,710) ​ ​ 4,638 ​ ​ (6,089) ​ ​ - ​ ​ (12,161) Income tax expense (benefit) ​ ​ (3,578) ​ ​ 1,549 ​ ​ (2,033) ​ ​ - ​ ​ (4,062) Net income (loss) ​ ​ (7,132) ​ ​ 3,088 ​ ​ (4,055) ​ ​ - ​ ​ (8,099) Segment assets (1) ​ ​ 323,070 ​ ​ 23,293 ​ ​ 58,650 ​ ​ (23,130) ​ ​ 381,883 (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 June 30, 2023 ​ Energy Engineering and Consulting Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 8,947 ​ $ 16,443 ​ $ 25,390 Unit-based ​ ​ 39,900 ​ ​ 3,818 ​ ​ 43,718 Fixed price ​ ​ 49,168 ​ ​ 801 ​ ​ 49,969 Total (1) ​ $ 98,015 ​ $ 21,062 ​ $ 119,077 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 7,440 ​ $ 1,376 ​ $ 8,816 Government ​ ​ 40,543 ​ ​ 19,610 ​ ​ 60,153 Utilities (2) ​ ​ 50,032 ​ ​ 76 ​ ​ 50,108 Total (1) ​ $ 98,015 ​ $ 21,062 ​ $ 119,077 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 98,015 ​ $ 21,062 ​ $ 119,077 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six months ended June 30, 2023 ​ Energy Engineering and Consulting Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 16,656 ​ $ 30,997 ​ $ 47,653 Unit-based ​ ​ 84,827 ​ ​ 7,434 ​ ​ 92,261 Fixed price ​ ​ 79,817 ​ ​ 1,949 ​ ​ 81,766 Total (1) ​ $ 181,300 ​ $ 40,380 ​ $ 221,680 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 14,159 ​ $ 2,540 ​ $ 16,699 Government ​ ​ 66,618 ​ ​ 37,705 ​ ​ 104,323 Utilities (2) ​ ​ 100,523 ​ ​ 135 ​ ​ 100,658 Total (1) ​ $ 181,300 ​ $ 40,380 ​ $ 221,680 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 181,300 ​ $ 40,380 ​ $ 221,680 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended July 1, 2022 ​ Energy Engineering and Consulting Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 7,587 ​ $ 13,340 ​ $ 20,927 Unit-based ​ ​ 42,544 ​ ​ 3,755 ​ ​ 46,299 Fixed price ​ ​ 34,545 ​ ​ 874 ​ ​ 35,419 Total (1) ​ $ 84,675 ​ $ 17,970 ​ $ 102,645 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 6,701 ​ $ 1,476 ​ $ 8,177 Government ​ ​ 29,861 ​ ​ 16,338 ​ ​ 46,199 Utilities (2) ​ ​ 48,114 ​ ​ 156 ​ ​ 48,270 Total (1) ​ $ 84,675 ​ $ 17,970 ​ $ 102,645 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 84,675 ​ $ 17,970 ​ $ 102,645 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six months ended July 1, 2022 ​ Energy Engineering and Consulting Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 16,405 ​ $ 26,341 ​ $ 42,746 Unit-based ​ ​ 85,501 ​ ​ 6,739 ​ ​ 92,240 Fixed price ​ ​ 57,655 ​ ​ 1,842 ​ ​ 59,497 Total (1) ​ $ 159,561 ​ $ 34,922 ​ $ 194,483 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 14,790 ​ $ 2,954 ​ $ 17,744 Government ​ ​ 48,220 ​ ​ 31,791 ​ ​ 80,011 Utilities (2) ​ ​ 96,551 ​ ​ 177 ​ ​ 96,728 Total (1) ​ $ 159,561 ​ $ 34,922 ​ $ 194,483 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 159,561 ​ $ 34,922 ​ $ 194,483 ​ (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 six months ended June 30, 2023 and July 1, 2022. ​ 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 22 U.S. states, the District of Columbia, the Commonwealth of Puerto Rico, and Canada. Revenues from the Company’s Puerto Rican and Canadian operations were not material for the three and six months ended June 30, 2023 nor the three and six months ended July 1, 2022. Customer Concentration For the three and six months ended June 30, 2023, the Company’s top 10 customers accounted for 51.7%, and 51.4%, respectively, of the Company’s consolidated contract revenue. For the three and six months ended July 1, 2022, the Company’s top 10 customers accounted for 55.4% , and 54.4% , respectively, of the Company’s consolidated contract revenue. For the three months ended June 30, 2023, the Company had two customers, Dormitory Authority-State New York (“DASNY”) and the Los Angeles Department of Water and Power (“LADWP”), that accounted for 10.7% and 10.3% of its consolidated contract revenues, respectively . . For the three and six months ended July 1, 2022, the Company had one customer, LADWP, that accounted for 14.6% and 15.8% , respectively, 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 June 30, 2023, the Company had two customers, DASNY and LADWP, that accounted for 13.0% and 12.5% of its Energy segment revenues, respectively. For the six months ended June 30, 2023, the Company had two customers, LADWP and DASNY, that accounted for 13.0% and 11.6% of its Energy segment revenues, respectively. For the three and six months ended June 30, 2023, no single customer accounted for 10% or more of . For the three and six months ended July 1, 2022, the Company derived 17.6% and 19.2% , respectively, of its Energy segment revenues from one customer, LADWP. For the three and six months ended July 1, 2022, no single customer accounted for 10% or more of its Engineering and Consulting segment revenues. On a geographical basis, the Company’s largest clients are based in California and New York. For the three and six months ended June 30, 2023, services provided to clients in California accounted for 41.4% and 41.9%, respectively, of the Company’s contract revenue and services provided to clients in New York accounted for 26.1% and 25.3%, respectively, of the Company’s contract revenue. For the three and six months ended July 1, 2022, services provided to clients in California accounted for 40.9% and 42.2%, respectively, of the Company’s contract revenue and services provided to clients in New York accounted for 19.6% and 20.2%, respectively, of the Company’s contract revenue.

INCOME TAXES

INCOME TAXES	6 Months Ended
	Jun. 30, 2023
INCOME TAXES
INCOME TAXES	9. 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 the Company’s 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. At the end of fiscal year 2022, the Company’s total valuation allowance was $1.2 million, remaining unchanged from the end of fiscal year 2021. As of June 30, 2023, 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 June 30, 2023, 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 three and six months ended June 30, 2023. 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. During the three and six months ended June 30, 2023, and three and six months ended July 1, 2022, the Company did not record 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 expense of $0.2 million and $1.0 million for the three and six months ended June 30, 2023, respectively, as compared to an income tax benefit of $1.7 million and $4.1 million for the three and six months ended April 1, 2022, respectively. During the three and six months ended June 30, 2023, the difference between the effective tax rate and the federal statutory rate was primarily attributable to state taxes, non-deductible stock compensation, nondeductible executive compensation, research and development tax credits, and the commercial building energy efficiency deduction. During the three and six months ended July 1, 2022, the difference between the effective tax rate and the federal statutory rate was primarily attributable to state taxes, non-deductible stock compensation, nondeductible executive compensation, research and development tax credits, and the commercial building energy efficiency deduction. ​

EARNINGS PER SHARE (EPS)

EARNINGS PER SHARE (EPS)	6 Months Ended
	Jun. 30, 2023
EARNINGS PER SHARE (EPS)
EARNINGS PER SHARE (EPS)	10. 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 ​ Six months ended ​ ​ June 30, ​ July 1, ​ June 30, ​ July 1, ​ 2023 2022 2023 2022 ​ ​ (in thousands, except per share amounts) Net income (loss) ​ $ 397 ​ $ (4,326) ​ $ 1,329 ​ $ (8,099) Weighted-average common shares outstanding ​ 13,344 ​ 13,016 ​ 13,305 ​ 12,901 Effect of dilutive stock options and restricted stock awards ​ 143 ​ — ​ 176 ​ — Weighted-average common shares outstanding-diluted ​ 13,487 ​ 13,016 ​ 13,481 ​ 12,901 Earnings (Loss) per share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic ​ $ 0.03 ​ $ (0.33) ​ $ 0.10 ​ $ (0.63) Diluted ​ $ 0.03 ​ $ (0.33) ​ $ 0.10 ​ $ (0.63) ​ For the three and six months ended June 30, 2023, the Company excluded 451,000 and 433,000 common shares, respectively, subject to outstanding equity awards from the calculation of diluted shares because their impact would have been anti-dilutive. For the three and six months ended July 1, 2022, the Company reported a net loss, and accordingly, all outstanding equity awards have been excluded from such periods because including them would have been anti-dilutive. ​

CONTINGENCIES

CONTINGENCIES	6 Months Ended
	Jun. 30, 2023
CONTINGENCIES
CONTINGENCIES	11. 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	6 Months Ended
	Jun. 30, 2023
SUBSEQUENT EVENTS
SUBSEQUENT EVENTS	12. 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 August 3, 2023, there were no subsequent events required to be reported. ​ ​ ​ ​ ​

ORGANIZATION AND OPERATIONS O_2

ORGANIZATION AND OPERATIONS OF THE COMPANY (Policies)	6 Months Ended
	Jun. 30, 2023
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 2023, which ends on December 29, 2023, will be comprised of 52 weeks, with all quarters consisting of 13 weeks each. Fiscal year 2022, which ended on December 30, 2022, was comprised of 52 weeks, with all 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.
Credit Agreement Refinancing	Credit Agreement Refinancing As described in Note 5, “ Debt Obligations Quantitative and Qualitative Disclosures About Market Risk In accordance with ASC Topic 205, when preparing financial statements for each reporting period, the Company evaluates whether there are conditions or events that, when considered in the aggregate, raise substantial doubt about the Company’s ability to continue as a going concern within one year after the date that the financial statements are issued. The Company considered its Credit Agreement’s principal and interest payment due on June 26, 2024 and assessed its current financial condition and liquidity sources, including current funds available, forecasted future cash flows, and conditional and unconditional obligations due over the next twelve months. Based on that analysis, only as a result of the Company’s obligation under the Credit Agreement to make final payment of all then remaining principal and interest on June 26, 2024, does an event arise which raises substantial doubt with respect to the Company's ability to continue as a going concern within one year after the date that the Condensed Consolidated Financial Statements are issued. The Company intends to refinance its Credit Agreement and has entered into an engagement to secure a new three-year financing facility with a syndicate of financial institutions as lenders which, among other things, will repay 100% of the obligations under the existing Credit Agreement and extend the due date of the maturity payment by more than two years from the current maturity date. The Company expects to finalize its refinancing efforts and enter into a new credit facility during the second half of fiscal 2023. Accordingly, the Company believes that its refinancing plan alleviates any substantial doubt about the Company's ability to continue as a going concern within one year after the date that the consolidated financial statements are issued because it expects to fully refinance the Credit Agreement with a new credit facility prior to June 26, 2024, the date on which final payment of all then remaining principal and interest under the current Credit Agreement is due.
Accounting Pronouncements Recently Adopted	As of June 30, 2023, there were no accounting pronouncements recently issued, or with future effective dates, that are either applicable nor are expected to have an impact to the Company’s Condensed Consolidated Financial Statements.
Revenue Recognition	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 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 June 30, 2023 and December 30, 2022, contract assets included retainage of approximately $12.5 million and $8.5 million, respectively.

REVENUES (Tables)

REVENUES (Tables)	6 Months Ended
	Jun. 30, 2023
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)	6 Months Ended
	Jun. 30, 2023
SUPPLEMENTAL FINANCIAL STATEMENT DATA
Schedule of reconciliation of cash and cash equivalents, and restricted cash	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 30, ​ 2023 2022 ​ ​ (in thousands) Cash and cash equivalents ​ $ 13,649 ​ $ 8,806 Restricted cash ​ — ​ 10,679 Total cash, cash equivalents, and restricted cash shown in the consolidated statement of cash flows ​ $ 13,649 ​ $ 19,485
Schedule of equipment and leasehold improvements	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 30, ​ 2023 2022 ​ ​ (in thousands) Furniture and fixtures ​ $ 4,188 ​ $ 4,062 Computer hardware and software ​ 40,434 ​ 35,635 Leasehold improvements ​ 3,832 ​ 3,097 Equipment under finance leases ​ 5,588 ​ 5,503 Automobiles, trucks, and field equipment ​ 3,135 ​ 3,134 Subtotal ​ 57,177 ​ 51,431 Accumulated depreciation and amortization ​ (31,683) ​ (28,894) Equipment and leasehold improvements, net ​ $ 25,494 ​ $ 22,537
Schedule of accrued liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, ​ December 30, ​ 2023 2022 ​ ​ (in thousands) Accrued subcontractor costs ​ $ 21,927 ​ $ 28,374 Accrued bonuses ​ ​ 6,758 ​ ​ 8,470 Employee withholdings ​ 2,795 ​ 2,571 Compensation and payroll taxes ​ 2,690 ​ 2,340 Rebate and other ​ ​ 303 ​ ​ 14,643 Accrued accounting and taxes ​ 2,481 ​ 2,712 Total accrued liabilities ​ $ 36,954 ​ $ 59,110
Schedule of changes in the carrying value of goodwill by reporting unit	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ December 30, ​ Additional ​ Additions / ​ June 30, ​ 2022 Purchase Cost Adjustments 2023 ​ ​ (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 acquired identifiable intangible assets with finite useful lives	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, 2023 ​ December 30, 2022 ​ ​ ​ ​ ​ ​ ​ ​ Gross ​ Accumulated ​ Gross ​ Accumulated ​ Amortization ​ Amount Amortization Amount Amortization Period ​ ​ (in thousands) ​ (in years) Finite: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Tradename ​ $ 15,911 ​ $ 11,986 ​ $ 15,911 ​ $ 10,990 2.5 ​ - ​ 6.0 Developed technology ​ ​ 15,810 ​ ​ 13,332 ​ ​ 15,810 ​ ​ 11,871 ​ 8.0 Customer relationships ​ ​ 58,149 ​ ​ 28,315 ​ ​ 58,149 ​ ​ 25,523 ​ 5.0 ​ - ​ 8.0 Total intangible assets ​ $ 89,870 ​ $ 53,633 ​ $ 89,870 ​ $ 48,384 ​ ​ ​ ​ ​ ​

DEBT OBLIGATIONS (Tables)

DEBT OBLIGATIONS (Tables)	6 Months Ended
	Jun. 30, 2023
DEBT OBLIGATIONS
Schedule of debt obligations, excluding obligations under capital leases	​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 30, ​ ​ 2023 ​ 2022 ​ ​ (in thousands) Outstanding borrowings on Term A Loan ​ $ 60,000 ​ $ 65,000 Outstanding borrowings on Revolving Credit Facility ​ ​ 5,000 ​ ​ — Outstanding borrowings on Delayed Draw Term Loan ​ ​ 37,000 ​ ​ 41,000 Other debt agreements ​ ​ 988 ​ ​ 1,958 Total debt ​ ​ 102,988 ​ ​ 107,958 Issuance costs and debt discounts ​ ​ (350) ​ ​ (511) Subtotal ​ ​ 102,638 ​ ​ 107,447 Less current portion of long-term debt ​ 102,619 ​ 16,903 Long-term debt portion ​ $ 19 ​ $ 90,544

LEASES (Tables)

LEASES (Tables)	6 Months Ended
	Jun. 30, 2023
LEASES
Summary of the Lease Expense	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three Months Ended ​ Six Months Ended ​ June 30, ​ July 1, ​ June 30, ​ July 1, ​ 2023 2022 2023 2022 ​ (in thousands) ​ (in thousands) Operating lease cost $ 1,664 ​ $ 1,534 ​ $ 3,157 ​ $ 3,112 Finance lease cost: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Amortization of assets ​ 318 ​ ​ 255 ​ ​ 629 ​ ​ 488 Interest on lease liabilities ​ 24 ​ ​ 15 ​ ​ 46 ​ ​ 29 Total net lease cost $ 2,006 ​ $ 1,804 ​ $ 3,832 ​ $ 3,629
Summary of Lease Information Presented on the Condensed Consolidated Balance Sheet	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ June 30, December 30, ​ ​ ​ 2023 ​ 2022 ​ ​ ​ (in thousands) ​ Operating leases: ​ ​ ​ ​ ​ ​ ​ Right-of-use assets ​ $ 13,894 ​ $ 12,390 ​ ​ ​ ​ ​ ​ ​ Lease liability ​ $ 4,877 ​ $ 4,625 ​ Lease liability, less current portion ​ 10,731 ​ 8,599 ​ Total lease liabilities ​ $ 15,608 ​ $ 13,224 ​ ​ ​ ​ ​ ​ ​ Finance leases (included in equipment and leasehold improvements, net): ​ ​ ​ ​ ​ ​ ​ Equipment and leasehold improvements, net ​ $ 5,588 ​ $ 5,503 ​ Accumulated depreciation ​ (3,266) ​ (2,830) ​ Total equipment and leasehold improvements, net ​ $ 2,322 ​ $ 2,673 ​ ​ ​ ​ ​ ​ ​ ​ Finance lease obligations ​ $ 1,143 ​ $ 1,113 ​ Finance lease obligations, less current portion ​ ​ 1,251 ​ ​ 1,601 ​ Total finance lease obligations ​ $ 2,394 ​ $ 2,714 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average remaining lease term (in years): ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ 3.60 ​ ​ 3.35 ​ Finance Leases ​ ​ 2.42 ​ ​ 2.66 ​ ​ ​ ​ ​ ​ ​ ​ ​ Weighted average discount rate: ​ ​ ​ ​ ​ ​ ​ Operating Leases ​ ​ 5.74 % ​ 4.25 % Finance Leases ​ ​ 4.06 % ​ 3.47 %
Summary of Other Information and Supplemental Cash Flow Information Related to Finance and Operating Leases	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six Months Ended ​ ​ June 30, ​ July 1, ​ ​ 2023 2022 ​ ​ (in thousands) Cash paid for amounts included in the measurement of lease liabilities: ​ ​ ​ ​ ​ ​ Operating cash flow from operating leases ​ $ 3,003 ​ $ 3,273 Operating cash flow from finance leases ​ ​ 46 ​ ​ 29 Financing cash flow from finance leases ​ ​ 599 ​ ​ 444 ​ ​ ​ ​ ​ ​ ​ Right-of-use assets obtained in exchange for lease liabilities: ​ ​ ​ ​ ​ ​ Operating leases ​ $ 4,264 ​ $ 1,002
Summary of the Maturities of Operating Lease Liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Finance ​ ​ (in thousands) ​ Fiscal year: ​ ​ ​ ​ ​ ​ ​ Remainder of 2023 ​ $ 2,793 ​ $ 681 ​ 2024 ​ 4,968 ​ 1,071 ​ 2025 ​ 3,988 ​ ​ 472 ​ 2026 ​ ​ 3,369 ​ ​ 211 ​ 2027 ​ ​ 1,519 ​ 80 ​ 2028 and thereafter ​ 816 ​ 7 ​ Total lease payments ​ ​ 17,453 ​ ​ 2,522 ​ Less: Imputed interest ​ (1,845) ​ ​ (128) ​ Total lease obligations ​ 15,608 ​ ​ 2,394 ​ Less: Current obligations ​ 4,877 ​ ​ 1,143 ​ Noncurrent lease obligations ​ $ 10,731 ​ $ 1,251 ​
Summary of the Maturities of Finance Lease Liabilities	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Operating Finance ​ ​ (in thousands) ​ Fiscal year: ​ ​ ​ ​ ​ ​ ​ Remainder of 2023 ​ $ 2,793 ​ $ 681 ​ 2024 ​ 4,968 ​ 1,071 ​ 2025 ​ 3,988 ​ ​ 472 ​ 2026 ​ ​ 3,369 ​ ​ 211 ​ 2027 ​ ​ 1,519 ​ 80 ​ 2028 and thereafter ​ 816 ​ 7 ​ Total lease payments ​ ​ 17,453 ​ ​ 2,522 ​ Less: Imputed interest ​ (1,845) ​ ​ (128) ​ Total lease obligations ​ 15,608 ​ ​ 2,394 ​ Less: Current obligations ​ 4,877 ​ ​ 1,143 ​ Noncurrent lease obligations ​ $ 10,731 ​ $ 1,251 ​

SEGMENT AND GEOGRAPHICAL INFO_2

SEGMENT AND GEOGRAPHICAL INFORMATION (Tables)	6 Months Ended
	Jun. 30, 2023
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 June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 98,015 ​ $ 21,062 ​ $ - ​ $ - ​ $ 119,077 Depreciation and amortization ​ ​ 3,877 ​ ​ 251 ​ ​ - ​ ​ - ​ ​ 4,128 Interest expense, net ​ ​ 1 ​ ​ - ​ ​ 2,206 ​ ​ - ​ ​ 2,207 Segment profit (loss) before income tax expense ​ ​ 603 ​ ​ 3,218 ​ ​ (3,181) ​ ​ - ​ ​ 640 Income tax expense (benefit) ​ ​ 207 ​ ​ 1,332 ​ ​ (1,296) ​ ​ - ​ ​ 243 Net income (loss) ​ ​ 397 ​ ​ 1,885 ​ ​ (1,885) ​ ​ - ​ ​ 397 Segment assets (1) ​ ​ 333,136 ​ ​ 23,851 ​ ​ 60,963 ​ ​ (23,130) ​ ​ 394,820 Fiscal Three Months Ended July 1, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 84,675 ​ $ 17,970 ​ $ - ​ $ - ​ $ 102,645 Depreciation and amortization ​ ​ 4,183 ​ ​ 243 ​ ​ - ​ ​ - ​ ​ 4,426 Interest expense, net ​ ​ 1 ​ ​ - ​ ​ 1,029 ​ ​ - ​ ​ 1,030 Segment profit (loss) before income tax expense ​ ​ (6,357) ​ ​ 2,531 ​ ​ (2,173) ​ ​ - ​ ​ (5,999) Income tax expense (benefit) ​ ​ (1,891) ​ ​ 732 ​ ​ (514) ​ ​ - ​ ​ (1,673) Net income (loss) ​ ​ (4,467) ​ ​ 1,798 ​ ​ (1,657) ​ ​ - ​ ​ (4,326) Segment assets (1) ​ ​ 323,070 ​ ​ 23,293 ​ ​ 58,650 ​ ​ (23,130) ​ ​ 381,883 Fiscal Six Months Ended June 30, 2023 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 181,300 ​ $ 40,380 ​ $ - ​ $ - ​ $ 221,680 Depreciation and amortization ​ ​ 7,801 ​ ​ 527 ​ ​ - ​ ​ - ​ ​ 8,328 Interest expense, net ​ ​ 3 ​ ​ - ​ ​ 4,670 ​ ​ - ​ ​ 4,673 Segment profit (loss) before income tax expense ​ ​ 3,374 ​ ​ 5,805 ​ ​ (6,851) ​ ​ - ​ ​ 2,328 Income tax expense (benefit) ​ ​ 1,448 ​ ​ 2,490 ​ ​ (2,939) ​ ​ - ​ ​ 999 Net income (loss) ​ ​ 1,927 ​ ​ 3,313 ​ ​ (3,911) ​ ​ - ​ ​ 1,329 Segment assets (1) ​ ​ 333,136 ​ ​ 23,851 ​ ​ 60,963 ​ ​ (23,130) ​ ​ 394,820 Fiscal Six Months Ended July 1, 2022 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Contract revenue ​ $ 159,561 ​ $ 34,922 ​ $ - ​ $ - ​ $ 194,483 Depreciation and amortization ​ ​ 8,340 ​ ​ 495 ​ ​ - ​ ​ - ​ ​ 8,835 Interest expense, net ​ ​ 5 ​ ​ - ​ ​ 1,776 ​ ​ - ​ ​ 1,781 Segment profit (loss) before income tax expense ​ ​ (10,710) ​ ​ 4,638 ​ ​ (6,089) ​ ​ - ​ ​ (12,161) Income tax expense (benefit) ​ ​ (3,578) ​ ​ 1,549 ​ ​ (2,033) ​ ​ - ​ ​ (4,062) Net income (loss) ​ ​ (7,132) ​ ​ 3,088 ​ ​ (4,055) ​ ​ - ​ ​ (8,099) Segment assets (1) ​ ​ 323,070 ​ ​ 23,293 ​ ​ 58,650 ​ ​ (23,130) ​ ​ 381,883 (1) Segment assets are presented net of intercompany receivables.
Schedule of disaggregation of revenue	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended June 30, 2023 ​ Energy Engineering and Consulting Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 8,947 ​ $ 16,443 ​ $ 25,390 Unit-based ​ ​ 39,900 ​ ​ 3,818 ​ ​ 43,718 Fixed price ​ ​ 49,168 ​ ​ 801 ​ ​ 49,969 Total (1) ​ $ 98,015 ​ $ 21,062 ​ $ 119,077 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 7,440 ​ $ 1,376 ​ $ 8,816 Government ​ ​ 40,543 ​ ​ 19,610 ​ ​ 60,153 Utilities (2) ​ ​ 50,032 ​ ​ 76 ​ ​ 50,108 Total (1) ​ $ 98,015 ​ $ 21,062 ​ $ 119,077 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 98,015 ​ $ 21,062 ​ $ 119,077 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six months ended June 30, 2023 ​ Energy Engineering and Consulting Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 16,656 ​ $ 30,997 ​ $ 47,653 Unit-based ​ ​ 84,827 ​ ​ 7,434 ​ ​ 92,261 Fixed price ​ ​ 79,817 ​ ​ 1,949 ​ ​ 81,766 Total (1) ​ $ 181,300 ​ $ 40,380 ​ $ 221,680 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 14,159 ​ $ 2,540 ​ $ 16,699 Government ​ ​ 66,618 ​ ​ 37,705 ​ ​ 104,323 Utilities (2) ​ ​ 100,523 ​ ​ 135 ​ ​ 100,658 Total (1) ​ $ 181,300 ​ $ 40,380 ​ $ 221,680 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 181,300 ​ $ 40,380 ​ $ 221,680 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended July 1, 2022 ​ Energy Engineering and Consulting Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 7,587 ​ $ 13,340 ​ $ 20,927 Unit-based ​ ​ 42,544 ​ ​ 3,755 ​ ​ 46,299 Fixed price ​ ​ 34,545 ​ ​ 874 ​ ​ 35,419 Total (1) ​ $ 84,675 ​ $ 17,970 ​ $ 102,645 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 6,701 ​ $ 1,476 ​ $ 8,177 Government ​ ​ 29,861 ​ ​ 16,338 ​ ​ 46,199 Utilities (2) ​ ​ 48,114 ​ ​ 156 ​ ​ 48,270 Total (1) ​ $ 84,675 ​ $ 17,970 ​ $ 102,645 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 84,675 ​ $ 17,970 ​ $ 102,645 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Six months ended July 1, 2022 ​ Energy Engineering and Consulting Total ​ (in thousands) Contract Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Time-and-materials ​ $ 16,405 ​ $ 26,341 ​ $ 42,746 Unit-based ​ ​ 85,501 ​ ​ 6,739 ​ ​ 92,240 Fixed price ​ ​ 57,655 ​ ​ 1,842 ​ ​ 59,497 Total (1) ​ $ 159,561 ​ $ 34,922 ​ $ 194,483 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Client Type ​ ​ ​ ​ ​ ​ ​ ​ ​ Commercial ​ $ 14,790 ​ $ 2,954 ​ $ 17,744 Government ​ ​ 48,220 ​ ​ 31,791 ​ ​ 80,011 Utilities (2) ​ ​ 96,551 ​ ​ 177 ​ ​ 96,728 Total (1) ​ $ 159,561 ​ $ 34,922 ​ $ 194,483 ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Geography (3) ​ ​ ​ ​ ​ ​ ​ ​ ​ Domestic ​ $ 159,561 ​ $ 34,922 ​ $ 194,483 ​ (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 six months ended June 30, 2023 and July 1, 2022.

EARNINGS PER SHARE (EPS) (Table

EARNINGS PER SHARE (EPS) (Tables)	6 Months Ended
	Jun. 30, 2023
EARNINGS PER SHARE (EPS)
Schedule of number of weighted-average common shares outstanding used to compute basic and diluted EPS	​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Three months ended ​ Six months ended ​ ​ June 30, ​ July 1, ​ June 30, ​ July 1, ​ 2023 2022 2023 2022 ​ ​ (in thousands, except per share amounts) Net income (loss) ​ $ 397 ​ $ (4,326) ​ $ 1,329 ​ $ (8,099) Weighted-average common shares outstanding ​ 13,344 ​ 13,016 ​ 13,305 ​ 12,901 Effect of dilutive stock options and restricted stock awards ​ 143 ​ — ​ 176 ​ — Weighted-average common shares outstanding-diluted ​ 13,487 ​ 13,016 ​ 13,481 ​ 12,901 Earnings (Loss) per share: ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ Basic ​ $ 0.03 ​ $ (0.33) ​ $ 0.10 ​ $ (0.63) Diluted ​ $ 0.03 ​ $ (0.33) ​ $ 0.10 ​ $ (0.63)

ORGANIZATION AND OPERATIONS O_3

ORGANIZATION AND OPERATIONS OF THE COMPANY - Segment Information (Details)	6 Months Ended
	Jun. 30, 2023 segment
Segment Information
Number of reporting segments	2

ORGANIZATION AND OPERATIONS O_4

ORGANIZATION AND OPERATIONS OF THE COMPANY - Fiscal Years (Details)	3 Months Ended								12 Months Ended
	Dec. 29, 2023	Sep. 29, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 30, 2022	Sep. 30, 2022	Jul. 01, 2022	Apr. 01, 2022	Dec. 29, 2023	Dec. 30, 2022
Entity Information
Length of fiscal period	91 days	91 days	91 days	91 days	91 days	91 days	91 days	91 days	364 days	364 days
Minimum
Entity Information
Length of fiscal period				91 days					364 days
Maximum
Entity Information
Length of fiscal period				98 days					371 days

ORGANIZATION AND OPERATIONS O_5

ORGANIZATION AND OPERATIONS OF THE COMPANY - Credit Agreement Refinancing (Details) - Notes Payable to Banks $ in Millions	6 Months Ended
	Jun. 30, 2023 USD ($)
Term A Loan
Debt Instrument [Line Items]
Periodic payment of principal	$ 2.5
Delayed Draw Term Loan Facility
Debt Instrument [Line Items]
Annual amortization of debt (as a percent)	2.50%
New financing facility
Debt Instrument [Line Items]
Term of debt	3 years
Percentage of existing credit agreement replaced	100%
New financing facility | Minimum
Debt Instrument [Line Items]
Extended maturity term	2 years

REVENUES - Segment Information

REVENUES - Segment Information (Details)	6 Months Ended
	Jun. 30, 2023 segment
Segment Information
Number of reporting segments	2

REVENUES - General Information

REVENUES - General Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jul. 01, 2022	Jun. 30, 2023	Jul. 01, 2022	Dec. 30, 2022
Revenue
Payroll taxes, bonuses and employee benefit costs for all Company personnel	$ 22,416	$ 20,439	$ 44,801	$ 39,796
Revenue of the entity recorded in which it acts solely in the capacity of an agent			0
Retained accounts receivable	$ 12,500		$ 12,500		$ 8,500
Maximum
Revenue
Percent of revenue (as a percent)	3%		3%
Minimum
Revenue
Percent of revenue (as a percent)	2%		2%
Cost of Sales
Revenue
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 - Restricted Cash (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022	Jul. 01, 2022	Dec. 31, 2021
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents
Cash and cash equivalents	$ 13,649	$ 8,806
Restricted cash		10,679
Total cash, cash equivalents, and restricted cash shown in the consolidated statement of cash flows	$ 13,649	$ 19,485	$ 5,811	$ 11,221
Restricted Cash, Statement of Financial Position	Restricted cash	Restricted cash

SUPPLEMENTAL FINANCIAL STATEM_4

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Equipment and Leasehold Improvements, Net - Tabular Disclosure (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022
Equipment and Leasehold Improvements
Equipment under finance leases	$ 5,588	$ 5,503
Equipment and leasehold improvements, gross	57,177	51,431
Accumulated depreciation and amortization	(31,683)	(28,894)
Total equipment and leasehold improvements, net	25,494	22,537
Furniture and Fixtures
Equipment and Leasehold Improvements
Equipment and leasehold improvements	4,188	4,062
Computer Hardware and Software
Equipment and Leasehold Improvements
Equipment and leasehold improvements	40,434	35,635
Leasehold Improvements
Equipment and Leasehold Improvements
Equipment and leasehold improvements	3,832	3,097
Automobiles Trucks and Field Equipment
Equipment and Leasehold Improvements
Equipment and leasehold improvements	$ 3,135	$ 3,134

SUPPLEMENTAL FINANCIAL STATEM_5

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Equipment and Leasehold Improvements, Net - Depreciation and Amortization Expense (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jul. 01, 2022	Jun. 30, 2023	Jul. 01, 2022	Dec. 30, 2022
Amortization Expense
Amortization expense	$ 318	$ 255	$ 629	$ 488	$ 1,100

SUPPLEMENTAL FINANCIAL STATEM_6

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022
Accrued Liabilities
Accrued subcontractor costs	$ 21,927	$ 28,374
Accrued bonuses	6,758	8,470
Employee withholdings	2,795	2,571
Compensation and payroll taxes	2,690	2,340
Rebate and other	303	14,643
Accrued accounting and taxes	2,481	2,712
Total accrued liabilities	$ 36,954	$ 59,110

SUPPLEMENTAL FINANCIAL STATEM_7

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Goodwill (Details) $ in Thousands	Jun. 30, 2023 USD ($)
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_8

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Finite-lived Intangible Assets - Gross Amounts and Accumulated Amortization (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022
Finite-Lived Intangible Assets
Total finite intangible assets	$ 89,870	$ 89,870
Accumulated Amortization	53,633	48,384
Trade Names
Finite-Lived Intangible Assets
Total finite intangible assets	15,911	15,911
Accumulated Amortization	11,986	10,990
Developed Technology Rights
Finite-Lived Intangible Assets
Total finite intangible assets	15,810	15,810
Accumulated Amortization	13,332	11,871
Customer Relationships
Finite-Lived Intangible Assets
Total finite intangible assets	58,149	58,149
Accumulated Amortization	$ 28,315	$ 25,523

SUPPLEMENTAL FINANCIAL STATEM_9

SUPPLEMENTAL FINANCIAL STATEMENT DATA - Finite-lived Intangible Assets - Amortization Period (Details)	Jun. 30, 2023
Trade Names | Minimum
Finite-Lived Intangible Assets
Amortization Period	2 years 6 months
Trade Names | Maximum
Finite-Lived Intangible Assets
Amortization Period	6 years
Developed Technology Rights
Finite-Lived Intangible Assets
Amortization Period	8 years
Customer Relationships | Minimum
Finite-Lived Intangible Assets
Amortization Period	5 years
Customer Relationships | Maximum
Finite-Lived Intangible Assets
Amortization Period	8 years

DEBT OBLIGATIONS - Composition

DEBT OBLIGATIONS - Composition (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022
Debt Obligations
Total debt	$ 102,988	$ 107,958
Issuance costs and debt discounts	(350)	(511)
Subtotal - total debt principal	102,638	107,447
Notes Payable to Banks | Term A Loan
Debt Obligations
Total debt	60,000	65,000
Notes Payable to Banks | Revolving Credit Facility
Debt Obligations
Total debt	5,000
Notes Payable to Banks | Delayed Draw Term Loan Facility
Debt Obligations
Total debt	37,000	41,000
Notes Payable, Other Payables | Other Debt
Debt Obligations
Total debt	$ 988	$ 1,958

DEBT OBLIGATIONS - Classificati

DEBT OBLIGATIONS - Classification (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022
Debt Obligations
Subtotal	$ 102,638	$ 107,447
Less current portion of long-term debt	102,619	16,903
Long-term debt portion	$ 19	$ 90,544

DEBT OBLIGATIONS - Credit Facil

DEBT OBLIGATIONS - Credit Facilities (Details) - Notes Payable to Banks $ in Millions	Apr. 28, 2023	Nov. 01, 2022 USD ($)	Jun. 26, 2019 USD ($)
Credit Agreement 2019
Debt Obligations
Debt instrument, covenants, total leverage ratio, maximum permitted to maintain	3.25
Debt Instrument, Covenants, Minimum Fixed Charge Coverage Ratio	1.20
Credit Agreement 2019 | Minimum
Debt Obligations
Commitment fee (as a percent)	0.15%
Credit Agreement 2019 | Maximum
Debt Obligations
Commitment fee (as a percent)	0.40%
Credit Agreement 2019 | Base Rate | Minimum
Debt Obligations
Spread on floating interest rate (as a percent)	0.125%
Credit Agreement 2019 | Base Rate | Maximum
Debt Obligations
Spread on floating interest rate (as a percent)	1.25%
Credit Agreement 2019 | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Minimum
Debt Obligations
Spread on floating interest rate (as a percent)	1.125%
Interest rate (as a percent)	0%
Credit Agreement 2019 | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Maximum
Debt Obligations
Spread on floating interest rate (as a percent)	2.25%
Term A Loan
Debt Obligations
Initial outstanding principal			$ 100
Revolving Credit Facility
Debt Obligations
Maximum borrowing capacity			50
Maximum borrowing capacity during the period from November 1, 2022 through the date on which financial statements and compliance documents have been received by the Administrative Agent for the fiscal quarter ending March 31, 2023		$ 10
Debt instrument, covenants, Total Leverage Ratio, access to accordion feature, high end of range		3
Letter of Credit | Minimum
Debt Obligations
Commitment fee (as a percent)	0.84%
Letter of Credit | Maximum
Debt Obligations
Commitment fee (as a percent)	1.688%
Delayed Draw Term Loan Facility
Debt Obligations
Maximum borrowing capacity			$ 50

LEASES - General Information (D

LEASES - General Information (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2023 USD ($)
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		6 Months Ended		12 Months Ended
	Jun. 30, 2023	Jul. 01, 2022	Jun. 30, 2023	Jul. 01, 2022	Dec. 30, 2022
Lease cost
Operating lease cost	$ 1,664	$ 1,534	$ 3,157	$ 3,112
Amortization of assets	318	255	629	488	$ 1,100
Interest on lease liabilities	24	15	46	29
Total net lease cost	$ 2,006	$ 1,804	$ 3,832	$ 3,629

LEASES - Consolidated Balance S

LEASES - Consolidated Balance Sheet (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022
Leases
Right-of-use assets	$ 13,894	$ 12,390
Operating leases, lease liabilities
Lease liability	4,877	4,625
Lease liability, less current portion	10,731	8,599
Total lease liabilities	15,608	13,224
Finance leases (included in equipment and leasehold improvements, net):
Equipment and leasehold improvements, net	5,588	5,503
Accumulated depreciation	(3,266)	(2,830)
Total equipment and leasehold improvements, net	$ 2,322	$ 2,673
Finance Lease, Right-of-Use Asset, Statement of Financial Position	Equipment and leasehold improvements, net	Equipment and leasehold improvements, net
Finance lease obligations
Finance lease obligations	$ 1,143	$ 1,113
Finance lease obligations, less current portion	1,251	1,601
Total finance lease obligations	$ 2,394	$ 2,714

LEASES - Additional Information

LEASES - Additional Information (Details)	Jun. 30, 2023	Dec. 30, 2022
Leases
Operating leases, weighted average remaining lease term	3 years 7 months 6 days	3 years 4 months 6 days
Finance leases, weighted average remaining lease term	2 years 5 months 1 day	2 years 7 months 28 days
Operating leases, weighted average discount rate	5.74%	4.25%
Finance leases, weighted average discount rate	4.06%	3.47%

LEASES - Rent Expense (Details)

LEASES - Rent Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jul. 01, 2022	Jun. 30, 2023	Jul. 01, 2022
LEASES
Rent expenses	$ 1.8	$ 1.7	$ 3.4	$ 3.3

LEASES - Supplemental Cash Flow

LEASES - Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2023	Jul. 01, 2022
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flow from operating leases	$ 3,003	$ 3,273
Operating cash flow from finance leases	46	29
Financing cash flow from finance leases	599	444
Right-of-use assets obtained in exchange for lease liabilities for operating leases	$ 4,264	$ 1,002

LEASES - Operating Leases - Mat

LEASES - Operating Leases - Maturities of Lease Liabilities (Details) $ in Thousands	Jun. 30, 2023 USD ($)
Operating
Remainder of 2023	$ 2,793
2024	4,968
2025	3,988
2026	3,369
2027	1,519
2028 and thereafter	816
Total lease payments	$ 17,453

LEASES - Operating Leases - Gro

LEASES - Operating Leases - Gross Difference (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022
Operating
Total lease payments	$ 17,453
Less: Imputed interest	(1,845)
Total lease liabilities	15,608	$ 13,224
Less: Current obligations	4,877	4,625
Noncurrent lease obligations	$ 10,731	$ 8,599

LEASES - Finance Leases - Matur

LEASES - Finance Leases - Maturities of Lease Liabilities (Details) $ in Thousands	Jun. 30, 2023 USD ($)
Finance
Remainder of 2023	$ 681
2024	1,071
2025	472
2026	211
2027	80
2028 and thereafter	7
Total lease payments	$ 2,522

LEASES - Finance Leases - Gross

LEASES - Finance Leases - Gross Difference (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022
Finance
Total lease payments	$ 2,522
Less: Imputed interest	(128)
Total finance lease obligations	2,394	$ 2,714
Less: Current obligations	1,143	1,113
Noncurrent lease obligations	$ 1,251	$ 1,601

COMMITMENTS AND VARIABLE INTE_2

COMMITMENTS AND VARIABLE INTEREST ENTITIES - Employee Benefit Plans (Details)	6 Months Ended
	Jun. 30, 2023 USD ($) Y	Jul. 01, 2022 USD ($)
Qualified Cash or Deferred Arrangement
Employee Benefit Plans
Maximum employee contribution as a percentage of compensation under 401(k) Plan (as a percent)	50%
Defined Contribution Plan, Tax Status	us-gaap:QualifiedPlanMember
Defined Contribution Plan
Employee Benefit Plans
Service period	3 months
Attained age | Y	21
Defined contribution plan, employer matching contribution, percent of match (as a percent)	50%
Defined contribution plan, employer matching contribution, percent of employees' gross pay (as a percent)	6%
Maximum employer contribution per employee	$ 3,000
Employer matching contributions	$ 1,600,000	$ 1,600,000

COMMITMENTS AND VARIABLE INTE_3

COMMITMENTS AND VARIABLE INTEREST ENTITIES - Variable Interest Entities (Details)	6 Months Ended
	Jun. 30, 2023 entity
COMMITMENTS AND VARIABLE INTEREST ENTITIES
Number of VIEs	1

SEGMENT AND GEOGRAPHICAL INFO_3

SEGMENT AND GEOGRAPHICAL INFORMATION - Segment Information (Details)	6 Months Ended
	Jun. 30, 2023 segment
Segment Information
Number of reporting segments	2

SEGMENT AND GEOGRAPHICAL INFO_4

SEGMENT AND GEOGRAPHICAL INFORMATION - Statement of Operations (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jul. 01, 2022	Apr. 01, 2022	Jun. 30, 2023	Jul. 01, 2022
Segment reconciliation
Contract revenue	$ 119,077		$ 102,645		$ 221,680	$ 194,483
Depreciation and amortization	4,128		4,426		8,328	8,835
Interest expense, net	2,207		1,030		4,673	1,781
Segment profit (loss) before income tax expense	640		(5,999)		2,328	(12,161)
Income tax expense (benefit)	243		(1,673)		999	(4,062)
Net Income (Loss)	397	$ 932	(4,326)	$ (3,773)	1,329	(8,099)
Energy
Segment reconciliation
Contract revenue	98,015		84,675		181,300	159,561
Engineering and Consulting
Segment reconciliation
Contract revenue	21,062		17,970		40,380	34,922
Operating Segments | Energy
Segment reconciliation
Contract revenue	98,015		84,675		181,300	159,561
Depreciation and amortization	3,877		4,183		7,801	8,340
Interest expense, net	1		1		3	5
Segment profit (loss) before income tax expense	603		(6,357)		3,374	(10,710)
Income tax expense (benefit)	207		(1,891)		1,448	(3,578)
Net Income (Loss)	397		(4,467)		1,927	(7,132)
Operating Segments | Engineering and Consulting
Segment reconciliation
Contract revenue	21,062		17,970		40,380	34,922
Depreciation and amortization	251		243		527	495
Segment profit (loss) before income tax expense	3,218		2,531		5,805	4,638
Income tax expense (benefit)	1,332		732		2,490	1,549
Net Income (Loss)	1,885		1,798		3,313	3,088
Corporate, Non-Segment
Segment reconciliation
Interest expense, net	2,206		1,029		4,670	1,776
Segment profit (loss) before income tax expense	(3,181)		(2,173)		(6,851)	(6,089)
Income tax expense (benefit)	(1,296)		(514)		(2,939)	(2,033)
Net Income (Loss)	$ (1,885)		$ (1,657)		$ (3,911)	$ (4,055)

SEGMENT AND GEOGRAPHICAL INFO_5

SEGMENT AND GEOGRAPHICAL INFORMATION - Segment Assets (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Dec. 30, 2022	Jul. 01, 2022
Segment Reporting
Segment assets	$ 394,820	$ 409,674	$ 381,883
Operating Segments | Energy
Segment Reporting
Segment assets	333,136		323,070
Operating Segments | Engineering and Consulting
Segment Reporting
Segment assets	23,851		23,293
Corporate, Non-Segment
Segment Reporting
Segment assets	60,963		58,650
Intersegment Eliminations
Segment Reporting
Segment assets	$ (23,130)		$ (23,130)

SEGMENT AND GEOGRAPHICAL INFO_6

SEGMENT AND GEOGRAPHICAL INFORMATION - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jul. 01, 2022	Jun. 30, 2023	Jul. 01, 2022
Revenue
Revenue	$ 119,077	$ 102,645	$ 221,680	$ 194,483
Domestic
Revenue
Revenue	119,077	102,645	221,680	194,483
Energy
Revenue
Revenue	98,015	84,675	181,300	159,561
Energy | Domestic
Revenue
Revenue	98,015	84,675	181,300	159,561
Engineering and Consulting
Revenue
Revenue	21,062	17,970	40,380	34,922
Engineering and Consulting | Domestic
Revenue
Revenue	21,062	17,970	40,380	34,922
Commercial
Revenue
Revenue	8,816	8,177	16,699	17,744
Commercial | Energy
Revenue
Revenue	7,440	6,701	14,159	14,790
Commercial | Engineering and Consulting
Revenue
Revenue	1,376	1,476	2,540	2,954
Government
Revenue
Revenue	60,153	46,199	104,323	80,011
Government | Energy
Revenue
Revenue	40,543	29,861	66,618	48,220
Government | Engineering and Consulting
Revenue
Revenue	19,610	16,338	37,705	31,791
Utilities
Revenue
Revenue	50,108	48,270	100,658	96,728
Utilities | Energy
Revenue
Revenue	50,032	48,114	100,523	96,551
Utilities | Engineering and Consulting
Revenue
Revenue	76	156	135	177
Time-and-Materials Contract
Revenue
Revenue	25,390	20,927	47,653	42,746
Time-and-Materials Contract | Energy
Revenue
Revenue	8,947	7,587	16,656	16,405
Time-and-Materials Contract | Engineering and Consulting
Revenue
Revenue	16,443	13,340	30,997	26,341
Unit-based Contract
Revenue
Revenue	43,718	46,299	92,261	92,240
Unit-based Contract | Energy
Revenue
Revenue	39,900	42,544	84,827	85,501
Unit-based Contract | Engineering and Consulting
Revenue
Revenue	3,818	3,755	7,434	6,739
Fixed-Price Contract
Revenue
Revenue	49,969	35,419	81,766	59,497
Fixed-Price Contract | Energy
Revenue
Revenue	49,168	34,545	79,817	57,655
Fixed-Price Contract | Engineering and Consulting
Revenue
Revenue	$ 801	$ 874	$ 1,949	$ 1,842

SEGMENT AND GEOGRAPHICAL INFO_7

SEGMENT AND GEOGRAPHICAL INFORMATION - Geographical Information (Details)	Jun. 30, 2023 state
SEGMENT AND GEOGRAPHICAL INFORMATION
Number of states in which entity operates	22

SEGMENT AND GEOGRAPHICAL INFO_8

SEGMENT AND GEOGRAPHICAL INFORMATION - Concentration Risk (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jul. 01, 2022	Jun. 30, 2023	Jul. 01, 2022
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Top Ten Customers
Concentration Risk
Concentration risk (as a percent)	51.70%	55.40%	51.40%	54.40%
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Los Angeles Department of Water and Power
Concentration Risk
Concentration risk (as a percent)	10.30%	14.60%	10.60%	15.80%
Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Dormitory Authority-State New York
Concentration Risk
Concentration risk (as a percent)	10.70%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | California
Concentration Risk
Concentration risk (as a percent)	41.40%	40.90%	41.90%	42.20%
Revenue from Contract with Customer Benchmark | Geographic Concentration Risk | New York
Concentration Risk
Concentration risk (as a percent)	26.10%	19.60%	25.30%	20.20%
Revenue from Contract with Customer, Segment Benchmark | Customer Concentration Risk | Los Angeles Department of Water and Power | Energy
Concentration Risk
Concentration risk (as a percent)	12.50%	17.60%	13%	19.20%
Revenue from Contract with Customer, Segment Benchmark | Customer Concentration Risk | Dormitory Authority-State New York | Energy
Concentration Risk
Concentration risk (as a percent)	13%		11.60%

INCOME TAXES - Valuation Allowa

INCOME TAXES - Valuation Allowance (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2023	Dec. 30, 2022	Dec. 31, 2021
INCOME TAXES
Valuation allowance			$ (1,200)	$ (1,200)
Increase (decrease) in valuation allowance	$ 0	$ 0

INCOME TAXES - Uncertain Tax Po

INCOME TAXES - Uncertain Tax Positions (Details) - USD ($) $ in Thousands	Jun. 30, 2023	Jul. 01, 2022
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued
Liability for uncertain tax positions	$ 0	$ 0

INCOME TAXES - Income Tax Expen

INCOME TAXES - Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jul. 01, 2022	Jun. 30, 2023	Jul. 01, 2022
INCOME TAXES
Income tax expense (benefit)	$ 243	$ (1,673)	$ 999	$ (4,062)

EARNINGS PER SHARE (EPS) - Comp

EARNINGS PER SHARE (EPS) - Computation (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jul. 01, 2022	Apr. 01, 2022	Jun. 30, 2023	Jul. 01, 2022
Net income (loss)
Net Income (Loss)	$ 397	$ 932	$ (4,326)	$ (3,773)	$ 1,329	$ (8,099)
Net income (loss) - basic	397		(4,326)		1,329	(8,099)
Net income (loss) - diluted	$ 397		$ (4,326)		$ 1,329	$ (8,099)
Weighted-average shares outstanding:
Weighted-average common shares outstanding (in shares)	13,344		13,016		13,305	12,901
Effect of dilutive stock options and restricted stock awards (in shares)	143				176
Weighted-average common shares outstanding-diluted (in shares)	13,487		13,016		13,481	12,901
Earnings (Loss) per share:
Basic (in dollars per share)	$ 0.03		$ (0.33)		$ 0.10	$ (0.63)
Diluted (in dollars per share)	$ 0.03		$ (0.33)		$ 0.10	$ (0.63)

EARNINGS PER SHARE (EPS) - Anti

EARNINGS PER SHARE (EPS) - Antidilutive Securities (Details) - shares shares in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2023	Jun. 30, 2023
Share-Based Payment Arrangement
Antidilutive securities
Antidilutive securities excluded from computation of earnings per share (in shares)	451	433

Pay vs Performance Disclosure

Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jul. 01, 2022	Apr. 01, 2022	Jun. 30, 2023	Jul. 01, 2022
Pay vs Performance Disclosure
Net Income (Loss)	$ 397	$ 932	$ (4,326)	$ (3,773)	$ 1,329	$ (8,099)

Insider Trading Arrangements

Insider Trading Arrangements	3 Months Ended
	Jun. 30, 2023
Trading Arrangements, by Individual
Rule 10b5-1 Arrangement Adopted	false
Non-Rule 10b5-1 Arrangement Adopted	false
Rule 10b5-1 Arrangement Terminated	false
Non-Rule 10b5-1 Arrangement Terminated	false