Snapshot
The Challenge
Our client identified a gap in B2B payments for the construction industry. Subcontractors on construction projects wait 60–90 days for payment. General contractors manage payments across dozens of subcontractors per project, each with different payment terms, retainage requirements, and lien waiver workflows. The process runs on spreadsheets, manual check cutting, and phone calls.
The founder’s vision: a platform where general contractors manage all subcontractor payments — from contract creation through payment release — with automated compliance documentation (lien waivers, insurance certificates) and flexible payment methods (ACH, wire, card).
Technical requirements:
- Payment processing: Multi-method payments via Stripe Connect with custom payment splits. A general contractor pays into the platform; funds are held and distributed to subcontractors based on payment schedules, retainage rules, and compliance verification.
- Compliance workflow: Before any payment releases, the system verifies: lien waiver submitted and valid, insurance certificate current, contract terms satisfied, and retainage calculations correct. Missing documentation blocks payment release automatically.
- Multi-user, multi-project: General contractors manage multiple projects. Each project has multiple subcontractors. Each subcontractor may work on multiple projects across multiple general contractors. The data model needed to handle these many-to-many relationships cleanly.
- PCI and financial compliance: Payment data handled securely. SOC 2 readiness from launch. Clear audit trail for every payment, every approval, and every compliance check.
- Budget constraint: $150K maximum for MVP. The seed round needed to fund 18 months of operations including sales, not just engineering.
Our Approach
Week 1: Data Assessment ($4,000)
We mapped every data source, every reporting need, and every manual process.
Data sources audited:
HubSpot CRM (contacts, companies, deals), Stripe (subscriptions, invoices, payments, refunds), PostgreSQL production DB (users, workspaces, feature usage events), Intercom (conversations, tags, resolution data), Google Analytics (traffic, acquisition), QuickBooks (GL, AP, AR), and Gusto (employee count, department structure).
Reporting needs identified (prioritized):
Assessment deliverable: A prioritized data architecture plan: ingest all 7 sources into a Snowflake data warehouse, build dbt transformation models for key metrics, and deploy self-serve dashboards in Metabase.
Month 2–3: Core Platform Build
General contractor dashboard: Project management interface showing all projects, subcontractors, payment schedules, and compliance status. Real-time view of: total outstanding payments, upcoming draws, compliance documents expiring within 30 days, and payment history with full audit trail.
Subcontractor portal: Each subcontractor gets a portal to: view their payment schedules across all projects, upload compliance documents (lien waivers, insurance certificates), track payment status (pending compliance → approved → processing → paid), and manage their bank account connection for receiving payments.
Compliance engine: Rules-based system that evaluates payment readiness:
- Lien waiver: uploaded, signed, covers the correct amount and period
- Insurance certificate: uploaded, current (not expired), coverage meets contract minimum
- Contract terms: draw amount matches contract schedule, retainage calculation correct
- Prior payments: previous draws in the sequence are settled
Each rule produces a pass/fail result with a specific reason for failure. The general contractor sees exactly what’s blocking each payment and can notify the subcontractor to provide missing documentation.
Retainage handling: Construction contracts typically withhold 5–10% of each payment as retainage, released upon project completion. The platform tracks retainage per subcontractor per project, calculates the withheld amount automatically, and manages retainage release as a separate payment event with its own compliance verification.
Month 4: Testing, Compliance, and Launch
Payment testing: We tested the complete payment flow with real Stripe test transactions: ACH debits (which take 5 business days to settle), instant card payments, failed payments (insufficient funds, expired cards), refunds, and split payments across multiple subcontractors from a single general contractor charge.
Edge case testing: Payment initiated but compliance document expires before settlement. Subcontractor’s bank account changes mid-payment cycle. General contractor disputes a payment after release. Partial draws (subcontractor requests 60% of a scheduled draw instead of 100%).
SOC 2 readiness: While not pursuing SOC 2 certification at launch (too early and expensive for a seed-stage company), we built the infrastructure with SOC 2 in mind: comprehensive audit logging, access controls with RBAC, encrypted data storage, documented change management process, and incident response procedures. When the company pursues SOC 2 (planned for post-Series A), the remediation effort will be minimal.
Security assessment: Penetration test conducted by a third-party firm. Two medium findings (both related to rate limiting on the API) remediated before launch. No critical or high findings.
The Results
Year 1 Performance
Year 1 Performance
Business Impact
For general contractors: Average payment processing time reduced from 3–5 business days (manual check cutting and mailing) to same-day or next-day ACH transfer. Compliance tracking went from spreadsheets and email to automated, real-time status across all subcontractors.
For subcontractors: Days Sales Outstanding (DSO) reduced from 67 days average to 12 days average. Subcontractors with immediate visibility into payment status reported higher satisfaction with general contractor relationships.
For the startup: The $41M in Year 1 processing volume at the platform’s fee structure generated sufficient revenue to demonstrate product-market fit. The founder used this traction to raise a $6.2M Series A, 14 months after the seed round.
Client Quote
“Most dev shops told us a payment platform would take 8–12 months and cost $300K+. Gigabit delivered in 4 months for under $140K — and the platform has processed $41 million without a single payment error. The double-entry ledger, the idempotency, the compliance automation — these aren’t features you see from teams that treat fintech like regular SaaS. Gigabit understood that in payments, reliability isn’t a feature, it’s the product.”
— CEO, [Client]
Investment Summary
Building A Fintech Product?
We engineer payment platforms, lending systems, and financial data products with
the compliance architecture and financial data integrity that fintech demands.