Enterprise SaaS Client
715 TSX files migrated across 16 apps and 28 libraries — 7× faster than the original 22-week estimate.
715
TSX files migrated
7×
Faster than estimated
94%
Cost reduction
22
Days to ship
The challenge
Where we found them
A mid-sized enterprise carried 16 applications and 28 shared libraries on a custom UI component system that had become a tax on every new feature. Scope: 715 TSX files, 705 Storybook stories, 485 unit tests, 99 end-to-end tests. The internal estimate for a manual migration was 22 weeks of senior engineering time — and even that assumed nothing else broke.
Our approach
How the fleet ran it
We ran the migration as an agent fleet engagement. Claude Code agents handled 90% of the mechanical refactors — component-by-component swaps, import rewrites, prop-shape updates, story regeneration. The senior engineer owned architecture decisions, code review, and the four cross-cutting changes the agents could not safely make. Every commit went through HITL review before landing on the branch.
Skills involved
- Code Migration Specialist
- Component Refactoring Agent
- Storybook Generation
- Test Migration
- PR Review Orchestrator
The outcome
What landed
The full migration shipped in 22 days — 7× faster than the manual estimate, with a 94% cost reduction against the prior £150K+ proposal from a traditional system integrator. Storybook coverage was preserved end-to-end; no unit or E2E suite required rewriting beyond the agent's mechanical edits.
Methodology
HITL gates between every step
Every engagement runs the same five-stage methodology — research, plan, execute, review, fix — with a senior engineer signing off at each gate. The agents handle the 80% that doesn't need a human; the 20% that does always gets one.
See the methodology in detailMore from the studio
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