SCHEDULE 13D

Sponsor is organized under the laws of the State of Delaware. Andrew R. Heyer and Steven J. Heyer are citizens of the United States. The address for the principal business office of each Reporting Person is 3024 Royal Palm Way, Suite 300-I, Palm Beach, FL 33480.

During the last five years, none of the Reporting Persons (i) has been convicted in any criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) was a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

During the last five years, none of the Reporting Persons (i) has been convicted in any criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) was a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

During the last five years, none of the Reporting Persons (i) has been convicted in any criminal proceeding (excluding traffic violations or similar misdemeanors) or (ii) was a party to a civil proceeding of a judicial or administrative body of competent jurisdiction and as a result of such proceeding was or is subject to a judgment, decree or final order enjoining future violations of, or prohibiting or mandating activities subject to, federal or state securities laws or finding any violation with respect to such laws.

DE and X1

Item 4 below summarizes certain provisions of the Business Combination Agreement (as defined below) that pertain to the securities acquired by the Reporting Persons. In connection with the closing of the Business Combination (as defined below), the Reporting Persons' existing securities in Haymaker Acquisition Corp. 4 were converted into securities of the Issuer.

Business Combination On April 8, 2026 (the "Closing Date"), the Issuer consummated its previously announced business combination (the "Closing") pursuant to that certain Business Combination Agreement, dated October 9, 2025 (the "Business Combination Agreement"), by and among the Issuer, Haymaker Acquisition Corp. 4, a Cayman Islands exempted company ("Haymaker" or "SPAC"), Haymaker Merger Sub I, Inc., a Delaware corporation and a direct wholly owned subsidiary of the Issuer ("Merger Sub I"), Haymaker Merger Sub II, LLC, a Delaware limited liability company and direct wholly owned subsidiary of the Issuer ("Merger Sub II"), and Concrete Partners Holding, LLC, a Delaware limited liability company ("Suncrete"). Immediately prior to the Closing, on April 8, 2026, Haymaker transferred by way of continuation out of its jurisdiction of incorporation from the Cayman Islands and domesticated into the State of Delaware (the "Domestication" and the time at which the Domestication became effective, the "Domestication Effective Time"). At the Domestication Effective Time (a) each SPAC Class A Ordinary Share that was issued and outstanding immediately prior to the Domestication Effective Time converted automatically, on a one-for-one basis, into one share of Class A Common Stock of the post-Domestication SPAC, par value $0.0001 per share ("SPAC Class A Common Stock"), (b) each Class B Ordinary Share of Haymaker, par value $0.0001 per share, that was issued and outstanding immediately prior to the Domestication Effective Time converted automatically, on a one-for-one basis, into one share of Class B Common Stock of the post-Domestication SPAC, par value $0.0001 per share ("SPAC Class B Common Stock"), and (c) each then-issued and outstanding private warrant to purchase SPAC Class A Ordinary Shares prior to the Domestication converted automatically, on a one-for-one basis, into one private warrant to purchase SPAC Class A Common Stock (a "SPAC Private Warrant"). On April 8, 2026, immediately following the Domestication, Merger Sub I merged with and into Haymaker (the "Initial Merger"), with Haymaker surviving the Initial Merger as a wholly owned subsidiary of the Issuer (the time at which the Initial Merger became effective, the "Initial Merger Effective Time"). At the Initial Merger Effective Time, among other things, (a) Sponsor distributed 2,800,000 shares of SPAC Class A Common Stock (the "Dothan Founder Shares") and 398,800 SPAC Private Warrants to Dothan Independent GP, LP ("Dothan Independent"), (b) each share of SPAC Class A Common Stock issued and outstanding immediately prior to the Initial Merger Effective Time was canceled and converted into one share of Class A Common Stock of the Issuer, par value $0.0001 per share ("Company Class A Common Stock"), (c) each share of SPAC Class B Common Stock issued and outstanding immediately prior to the Initial Merger Effective Time was canceled and converted into one share of Class B Common Stock of the Issuer, par value $0.0001 per share ("Company Class B Common Stock" and, together with the Issuer Class A Common Stock, the "Company Common Stock") and (d) each then-outstanding SPAC Private Warrant was automatically assumed and converted into a private warrant to purchase one share of Company Class A Common Stock ("Company Warrants"). On April 8, 2026, immediately following the Initial Merger, Merger Sub II merged with and into Suncrete (the "Acquisition Merger" and, together with the Initial Merger, the "Mergers", and together with the Domestication, the Warrant Redemption and all other transactions contemplated by the Business Combination Agreement, the "Business Combination" and the time at which the Acquisition Merger became effective, the "Acquisition Merger Effective Time"), with Suncrete surviving the Acquisition Merger as a wholly owned subsidiary of the Issuer. At the Acquisition Merger Effective Time, among other things, (a) each share of Company Class B Common Stock issued and outstanding immediately prior to the Acquisition Merger Effective Time (other than the Dothan Founder Shares) was converted into and exchanged, on a one-for-one basis, into one share of Company Class A Common Stock, (b) the Issuer issued 14,117,894 shares of Company Class A Common Stock to members of Suncrete, (c) the Issuer issued 3,481,776 shares of restricted Company Class A Common Stock upon the cancelation and conversion of the incentive units granted to management of Suncrete ("Rollover Equity Awards"), (d) the Issuer issued 18,414,609 shares of Company Class B Common Stock to members of Suncrete, and (e) the Issuer issued 2,500,000 shares of Company Class B Common Stock to Dothan Independent. The Issuer also issued to the Sponsor 179,227 shares of Company Class A Common Stock upon conversion and satisfaction of certain promissory notes previously issued by the SPAC to the Sponsor. Amended and Restated Registration Rights Agreement In connection with the Initial Closing, the Issuer, Haymaker, and Sponsor entered into an Amended and Restated Registration Rights Agreement (the "A&R Registration Rights Agreement") amending and restating the existing Registration Rights Agreement, dated as of July 25, 2023, by and between Haymaker and Sponsor and certain other equityholders of Haymaker, pursuant to which, among other things, the Issuer agreed to register for resale on Form S-1 or, if available, Form S-3, pursuant to Rule 415 under the Securities Act of 1933, as amended (the "Securities Act"), certain securities of the Company that are held by Sponsor. Under the A&R Registration Rights Agreement, the Issuer agreed to indemnify holders of registrable securities and their respective officers, directors and each person who controls such holders (within the meaning of the Securities Act) against all losses, claims, damages, liabilities and expenses (including attorneys' fees) resulting from any untrue or alleged untrue statement, or omission or alleged omission of a material fact in any registration statement, prospectus or any amendment thereof or supplement thereto pursuant to which such holders sell their registrable securities, unless such liability arose from such holder's misstatement or alleged misstatement, or omission or alleged omission, and such holders agreed to indemnify the Issuer, its officers and directors and agents and each person who controls the Issuer (within the meaning of the Securities Act) against any losses, claims, damages, liabilities and expenses (including without limitation reasonable attorneys' fees) resulting from any untrue statement of material facts or any omission of a material fact in any registration statement, prospectus or any amendment thereof or supplement thereto pursuant to which such holders sell their registrable securities. Sponsor Support Letter Agreement Concurrently with the execution and delivery of the Business Combination Agreement, the Sponsor and certain officers and directors of SPAC (such holders, the "Sponsor Related Parties") entered into an agreement (the "Sponsor Support Agreement") with Suncrete and the Issuer, which supersedes the letter agreement dated July 25, 2023, among the SPAC, Sponsor and the Sponsor Related Parties. Pursuant to the Sponsor Support Agreement, among other things, Sponsor and the Sponsor Related Parties agreed to vote in favor of the adoption and approval of the Business Combination Agreement and the transactions contemplated thereby and waive the anti-dilution rights set forth in SPAC's organizational documents. The Sponsor and Sponsor Related Parties also agreed, until the earlier of the Initial Closing and the termination of the Business Combination Agreement in accordance with its terms, not to (i) directly or indirectly sell, assign, transfer (including by operation of law), permit the creation of any lien, pledge, dispose of or otherwise encumber any of its SPAC securities or otherwise agree to do any of the foregoing, (ii) deposit any of its SPAC securities into a voting trust or enter into a voting agreement or arrangement or grant any proxy or power of attorney with respect thereto, (iii) enter into any contract, option or other arrangement or undertaking with respect to the direct or indirect acquisition or sale, assignment, transfer (including by operation of law) or other disposition of any of its SPAC securities, or (iv) take any action that would have the effect of preventing or disabling the Sponsor from performing its obligations under the Sponsor Support Agreement. Sponsor also agreed that, immediately upon the occurrence of the Initial Merger Effective Time, it will automatically be deemed to have irrevocably transferred to PubCo, surrendered and forfeited for no consideration 333,333 shares of PubCo Class A Common Stock. The Sponsor and Sponsor Related Parties have also agreed to certain transfer restrictions with respect to their PubCo Class A Common Stock as follows: during the period commencing from the Closing Date and ending on the earlier of (i) the one year anniversary of the Closing Date and (ii) the date after the Closing Date on which the Issuer consummates a liquidation, merger, share exchange, reorganization or other similar transaction with an unaffiliated third party that results in all of the Issuer's stockholders having the right to exchange their equity holdings in the Issuer for cash, securities or other property , each Sponsor Related Party agreed that it shall not, directly or indirectly, without the prior written consent of the Issuer, (i) sell, assign, transfer (including by operation of law), permit the creation of any lien, pledge, dispose of or otherwise encumber any of its Company Class A Common Stock or otherwise agree to do any of the foregoing, (ii) deposit any of its Company Class A Common Stock into a voting trust or enter into a voting agreement or arrangement or grant any proxy or power of attorney with respect thereto that is inconsistent with the Sponsor Support Agreement, or (iii) enter into any contract, option or other arrangement or undertaking with respect to the direct or indirect acquisition or sale, assignment, transfer (including by operation of law) or other disposition of any of its Company Class A Common Stock, subject to certain exceptions. Notwithstanding the foregoing, pursuant to the Sponsor Support Agreement, (i) 33.33% of the locked-up securities held by the applicable holder as of the Closing Date will be automatically released from the lock-up restrictions on the six month anniversary of the Closing Date and (ii) 33.33% of the locked-up securities held by the applicable holder as of the Closing Date will be automatically released from the lock-up restrictions on the nine month anniversary of the Closing Date. Indemnification of Directors and Officers Concurrently with the Closing, the Issuer entered into indemnification agreements with its directors and executive officers, including Mr. Heyer. Each indemnification agreement provides that, subject to limited exceptions, the Issuer will indemnify the applicable indemnified person to the fullest extent permitted by law for claims arising in his or her capacity as a director or officer of the Issuer, as applicable. General The Reporting Persons acquired the securities described in this Schedule 13D for investment purposes and intend to review their investments in the Issuer on a continuing basis. Subject to the terms of the Letter Agreement, any actions the Reporting Persons might undertake may be made at any time and from time to time without prior notice and will be dependent upon the Reporting Persons' review of numerous factors, including, but not limited to: an ongoing evaluation of the Issuer's business, financial condition, operations and prospects; price levels of the Issuer's securities; general market, industry and economic conditions; the relative attractiveness of alternative business and investment opportunities; and other future developments. Subject to applicable law, the Reporting Persons may acquire additional securities of the Issuer, or retain or sell all or a portion of the securities then held, in the open market or in privately negotiated transactions, including pursuant to registered transactions pursuant to the A&R Registration Rights Agreement. In addition, the Reporting Persons and their representative(s) to the Issuer's board of directors may engage in discussions with management, the Issuer's board of directors, and securityholders of the Issuer and other relevant parties or encourage, cause or seek to cause the Issuer or such persons to consider or explore extraordinary corporate transactions, such as: a merger, reorganization or other transaction that could result in the de-listing or de-registration of the Company Common Stock; sales or acquisitions of assets or businesses; changes to the capitalization or dividend policy of the Issuer; or other material changes to the Issuer's business or corporate structure, including changes in management or the composition of the Board. There can be no assurance, however, that any Reporting Person will propose such a transaction or that any such transaction would be successfully implemented. Other than as described above, the Reporting Persons do not currently have any plans or proposals that relate to, or would result in, any of the matters listed in Items 4(a)-(j)?of Schedule 13D, although, depending on the factors discussed herein, the Reporting Persons may change their purpose or formulate different plans or proposals with respect thereto at any time.

The following sets forth, as of the date of this Schedule 13D, the aggregate number of shares of Class A Common Stock and percentage of Company Class A Common Stock beneficially owned by each of the Reporting Persons, as well as the number of shares of Class A Common Stock as to which each Reporting Person has the sole power to vote or to direct the vote, shared power to vote or to direct the vote, sole power to dispose or to direct the disposition of or shared power to dispose or to direct the disposition of, as of the date hereof, based on 46,879,768 shares of Class A Common Stock outstanding as of the Closing Date. Shared Sole power Shared Sole power power to to dispose power to Amount to vote or to vote or to or to direct dispose or beneficially Percent direct the direct the the to direct the Reporting Person owned of class vote vote disposition disposition Haymaker Sponsor IV LLC 3,639,267 7.7% 0 0 3,593,494 0 Andrew R. Heyer 3,593,494 7.7% 0 3,593,494 0 3,593,494 Steven J. Heyer 3,593,494 7.7% 0 3,593,494 0 3,593,494 The Sponsor is the record holder of the securities reported herein. Andrew R. Heyer and Steven J. Heyer are managing members of the Sponsor. By virtue of this relationship, Messrs. Heyer and Heyer may be deemed to share beneficial ownership of the securities held of record by Sponsor. Messrs. Heyer and Heyer disclaim any such beneficial ownership except to the extent of their pecuniary interest therein.

The following sets forth, as of the date of this Schedule 13D, the aggregate number of shares of Class A Common Stock and percentage of Company Class A Common Stock beneficially owned by each of the Reporting Persons, as well as the number of shares of Class A Common Stock as to which each Reporting Person has the sole power to vote or to direct the vote, shared power to vote or to direct the vote, sole power to dispose or to direct the disposition of or shared power to dispose or to direct the disposition of, as of the date hereof, based on 46,879,768 shares of Class A Common Stock outstanding as of the Closing Date. Shared Sole power Shared Sole power power to to dispose power to Amount to vote or to vote or to or to direct dispose or beneficially Percent direct the direct the the to direct the Reporting Person owned of class vote vote disposition disposition Haymaker Sponsor IV LLC 3,639,267 7.7% 0 0 3,593,494 0 Andrew R. Heyer 3,593,494 7.7% 0 3,593,494 0 3,593,494 Steven J. Heyer 3,593,494 7.7% 0 3,593,494 0 3,593,494 The Sponsor is the record holder of the securities reported herein. Andrew R. Heyer and Steven J. Heyer are managing members of the Sponsor. By virtue of this relationship, Messrs. Heyer and Heyer may be deemed to share beneficial ownership of the securities held of record by Sponsor. Messrs. Heyer and Heyer disclaim any such beneficial ownership except to the extent of their pecuniary interest therein.

The Reporting Persons have not effected any transactions of the Issuer's Common Stock during the 60 days preceding the date of this report, except as described in Item 3 and Item 4 of this Schedule 13D, which information is incorporated herein by reference.

None.

Not applicable.

Item 4 above summarizes certain provisions of the Business Combination Agreement, A&R Registration Rights Agreement, and Sponsor Support Agreement and is incorporated herein by reference. Copies of these agreements are attached as exhibits to this Schedule 13D, and are incorporated herein by reference. Except as set forth herein, none of the Reporting Persons or Related Persons has any contracts, arrangements, understandings or relationships (legal or otherwise) with any person with respect to any securities of the Issuer, including but not limited to any contracts, arrangements, understandings or relationships concerning the transfer or voting of such securities, finder's fees, joint ventures, loan or option arrangements, puts or calls, guarantees of profits, division of profits or losses, or the giving or withholding of proxies.

Exhibit Number Description 1 Joint Filing Agreement. 2 Business Combination Agreement (Incorporated by reference to Exhibit 2.1 to Haymaker's Current Report on Form 8-K/A, filed with the SEC on October 14, 2025). 3 Amended and Restated Registration Rights Agreement, dated April 8, 2026, by and among the Issuer and Sponsor (Incorporated by reference to Exhibit 10.1 to the Issuer's Current Report on Form 8-K, filed with the SEC on April 14, 2026). 4 Sponsor Support Agreement, dated October 9, 2025, by and among Haymaker, the Issuer, Suncrete and the other parties signatory thereto (Incorporated by reference to Exhibit 10.2 to Haymaker's Current Report on Form 8-K, filed with the SEC on October 10, 2025 (as amended on October 14, 2025)).