Agent-driven monorepo refactor lands 3215 commits, cutting TS build time from 70s to 5s

Developer rchaves opened an agent-driven Draft PR in the langwatch repo, introducing domain-driven architecture separation across the entire monorepo, with the merged branch containing 3215 commits. The case drew wide community attention, and he subsequently open-sourced his orchestrate skill, with developers like janwilmake asking about methodologies for orchestrating large-scale agent work.

Confirmed

• Refactoring motivation: the same integration had up to six different implementations in the codebase, requiring unified governance
• rchaves built a dedicated harness for this massive PR and noted that ongoing rewrites are still needed as merges land on main
• The orchestrate skill centers on a disciplined delivery process: it forces BDD-spec-driven agents to deliver complete PRs, and the related code has been open-sourced
• On cost: the team used a bundled plan with all usage recorded, with details posted in PR comments; some Kimi was also used during the process but not counted in the statistics
• After seeing the PR, janwilmake publicly asked what resources exist for learning to orchestrate agents making large-scale code changes spanning thousands of lines

Why it matters

• This case provides public, verifiable evidence of agents completing a large refactor end to end: motivations, orchestration discipline, cost breakdowns, and side benefits are all documented rather than just marketing
• Hard numbers included: dev environment TypeScript compile time dropped from about 70 seconds to about 5 seconds; when teased about deleting more lines of code, rchaves said the team has no further plans for now
• Community inquiries into orchestration methods (janwilmake) show that experience orchestrating large-scale agent refactors is becoming a new learning hotspot

2026-09-20 ~ 2026-09-20 · 5 related posts

• [source] Agent-Driven PR With 3,215 Commits Refactors Entire Monorepo, Cutting TS Compile Time 70s to 5s — _rchaves_ · 2026-09-20
• [source] Side Effect of Agent Refactor: Dev TypeScript Compile Time Drops From ~70s to ~5s — janwilmake · 2026-09-20
• "How Do You Orchestrate Agents for Massive Code Changes?" Devs Ask After 3,215-Commit PR — janwilmake · 2026-09-20
• How Much Did That Agent-Driven Refactor Cost? Dev Says It's All in the PR Comments — _rchaves_ · 2026-09-20
• [source] Dev Open-Sources 'orchestrate' Skill: BDD Specs, Real Tests, Full PR Delivery Loop — _rchaves_ · 2026-09-20