SubcontractorStack is a compliance and documentation OS for small construction subcontractors (HVAC, electrical, roofing) drowning in GC portals, safety forms, and lien waivers. Right now, office managers manually re-enter the same data into Procore, email, and PDF forms, causing delays and payment holds. SubcontractorStack offers pre-built GC-specific form packs, auto-fill from a central company profile, and mobile upload for jobsite photos and signatures. - Normalizes requirements across major GCs and auto-generates compliant packets (insurance certs, safety training logs, MSDS). - Tracks conditional/final lien waivers and change orders, reducing collections time and disputes. - Provides a simple field app for supervisors to complete daily reports with voice and photo capture. - SaaS per-seat pricing, starting with US regional subcontractors that already use Procore/Buildertrend but lack their own ops layer.