Legacy billing rewrite estimated at 7-8 months shipped in six, 122 PRs in 90 days
alex_verem · x · 2026-10-08
A delivery orchestration company estimated 7-8 months to replace its legacy billing system. With two embedded engineers, it went to production in six months and merged 122 PRs in the first 90 days.
The key move: no code in week one. The team scanned the repo and built a knowledge graph documenting architecture, dependencies, data flows, and integration rules, which their agents consumed before every change. The author argues this is where teams go wrong — letting AI edit without context around existing workflows, downstream systems, and financial consistency.
Related event: Two Engineers Replace Legacy Billing System in Six Months with AI(2 posts)→
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