Success stories
From a 6,000+ Line Vibe-Coded Monolith to a Modular Architecture
Incremental migration (Strangler Fig pattern) with zero downtime, executed while the product was already in an active testing phase with real users.
4 WEEKS ACTUAL DELIVERY
VS
4 MONTHS ESTIMATED WITHOUT THIS APPROACH
This migration’s speed is a direct result of using AI as a tool guided by architectural judgment — to execute exactly what’s needed, the way it’s needed — rather than using it without that judgment, which is precisely what produced the original monolith.
Context
A digital education platform for children with learning difficulties, structured into 11 lessons with multiple videos each. Fully voice-first experience — no dependence on on-screen reading — with specific requirements around audio synchronization and per-lesson progress tracking. At the time of the project, the product was an MVP about to enter a testing phase with real users.
Technical Diagnosis
The frontend had been built entirely through vibe coding: a Project Manager without a developer background used Claude Code to generate the full interface, iterating prompt by prompt until each screen «worked» — with no architecture layer sitting above those iterations. Core symptom: a single file with more than 6,000 lines concentrating UI, business logic, and state management, with no separation of responsibilities.
▸ Tight UI ↔ logic coupling: with no abstraction layer, a visual change carried functional risk, and vice versa.
▸ Non-centralized state: each lesson’s progress was handled at the component level instead of being persisted centrally — the root cause behind the progresshistory failures.
▸ No boundaries by functional domain: a change in video playback could break navigation or tracking with no apparent relationship.
▸ Growing cost of change: every additional iteration widened the risk surface of the same file.
Architecture & Migration
Mindtech’s team didn’t approach this as a rewrite, but as an incremental Strangler Fig migration: the standard pattern for replacing a legacy system without taking it down, building the new architecture in parallel and redirecting functionality piece by piece.
▸ Functional mapping of the monolith before touching any code, identifying which block corresponded to which business functionality.
▸ Decoupled component architecture, organized by functional domain, with explicit interfaces and state separated from presentation.
▸ Incremental extraction validated against production at every step — no bigbang releases, no downtime windows.
▸ Centralized persistence layer for progress, resolving the lesson-progress history issue.
▸ Controlled coexistence between legacy and new code until the monolith was fully removed.
Before → After
6K+ lines
1 FILE
STRANGLER FIG →
Zero downtime
Modular architecture
ARCHITECTURE
From 1 monolithic file to modular components with scoped responsibilities.
BLAST RADIUS
Bugs and changes contained within their component, without spreading system-wide.
STATE
Centralized, persistent user progress — no longer handled ad hoc per screen.
CONTINUITY
Zero interruptions for testing-phase users throughout the entire migration.