os.construction blogNotes from building the operating system for construction: projects, accounting, analytics and AI agents on one data core.https://os.construction/en-usBuilding in public: the founding contractor programhttps://os.construction/blog/building-in-public-founding-contractor-program/https://os.construction/blog/building-in-public-founding-contractor-program/Construction has been sold a lot of software that demoed well and fell apart at the first month-end close. We'd rather build with contractors in the open. Here's what the founding program is, what we'll ask, and what we don't know yet.Sat, 10 Oct 2026 00:00:00 GMTCompanyPlatformRetainage, lien waivers and pay apps on one recordhttps://os.construction/blog/retainage-lien-waivers-pay-apps-one-record/https://os.construction/blog/retainage-lien-waivers-pay-apps-one-record/A pay app, the retainage it withholds and the lien waivers that release it are one transaction. Most contractors track them in three places. Here's how each piece works and why they belong together.Mon, 05 Oct 2026 00:00:00 GMTBillingAccountingAgents with approvals: how we think about AI in the back officehttps://os.construction/blog/agents-with-approvals/https://os.construction/blog/agents-with-approvals/AI in construction accounting goes wrong in two ways: chatbots that know nothing about your jobs, and autopilots that post entries nobody checked. Our model is an apprentice with a supervisor. Here are the rules.Wed, 30 Sep 2026 00:00:00 GMTAI agentsAccountingPlatformWIP shouldn't be a month-end projecthttps://os.construction/blog/wip-shouldnt-be-a-month-end-project/https://os.construction/blog/wip-shouldnt-be-a-month-end-project/The work-in-progress schedule is the most important report a contractor produces, and most build it from four sources a week after the month closes. Here's the math, what over and under billing really tell you, and why WIP should be live.Thu, 24 Sep 2026 00:00:00 GMTAccountingWIPThe real cost of re-keying a change orderhttps://os.construction/blog/real-cost-of-rekeying-a-change-order/https://os.construction/blog/real-cost-of-rekeying-a-change-order/We followed one change order from a ceiling cavity to the pay app and counted every time someone retyped the same facts. The typing is the cheap part.Sat, 19 Sep 2026 00:00:00 GMTChange ordersFieldPlatformWhy construction needs an operating system, not another apphttps://os.construction/blog/why-construction-needs-an-operating-system/https://os.construction/blog/why-construction-needs-an-operating-system/Most contractors don't have a software problem. They have a seams problem: the same number lives in five systems and none of them agree. The fix is a shared record, not another tool.Tue, 15 Sep 2026 00:00:00 GMTPlatformStrategy