Cleanroom Development & Legacy Re‑Engineering
Rebuild critical systems without dragging their baggage into the future. Use AI‑assisted cleanroom engineering to preserve behaviour and business value while avoiding licence lock‑in and copied code.
What We Mean by Cleanroom
Cleanroom development is a way to recreate or re‑engineer an existing system without copying its proprietary source code. Instead of reading the old codebase (or vendor sources you may not have), we treat the running system and its artefacts as the specification.
We observe behaviour, APIs and data contracts; analyse UI, databases, logs and traffic; and use available documentation and domain experts to fill gaps. From there, we build a new implementation from scratch on a modern stack.
With modern coding agents and LLMs, we can analyse UI, APIs, databases, traffic, logs and even compiled artefacts to recover the real business rules and flows. Engineers stay in control; AI accelerates requirements extraction, architecture proposals and implementation.
The result is a legally clean, modern codebase that behaves like (or better than) the original system, while removing vendor lock‑in, obsolete stacks and excessive licence costs.
Two Cleanroom Scenarios We Focus On
1. You own the legacy code, but the stack is killing you
You built or acquired the system years ago and still own the sources, but the technology stack is obsolete, risky or unstaffable. Changes are slow, fragile and expensive, and the surrounding toolchain is a mess of one‑off scripts and workarounds.
In this scenario, we rebuild what you already own on a modern, observable, cloud‑ready foundation. Business rules, data models and critical workflows are preserved; technology debt is not.
2. You are trapped in a vendor’s product you don’t control
The system is proprietary: you run it, but you don't own the code. Licence and support costs keep climbing; roadmap and integrations are dictated by the vendor; regulatory, security or geopolitical constraints make staying risky.
Here, we treat the running product as a black‑box specification and build a new implementation that matches its behaviour, APIs and UX closely enough that your users and integrations can move with minimal friction—without copying vendor code.
In both scenarios, the outcome is the same: a legally clean, modern codebase that behaves like (or better than) the original, and that you fully own.
Why Teams Choose Cleanroom
Reduce Licence & Support Costs
Replace expensive or sanctioned products with a functionally equivalent system you fully control. Savings come from both licences and the long tail of auxiliary tools around the old stack.
Eliminate Vendor Lock‑In
Stop being hostage to roadmap and pricing decisions of a single vendor. A clean implementation gives you freedom to evolve the system on your own terms.
Modernise IT Landscape
Move away from brittle, opaque stacks to modern, observable architectures. Cleanroom projects are an opportunity to rationalise integrations and simplify operations.
Improve Security & Compliance
Design security, auditability and regulatory constraints into the new system from day one instead of inheriting historical debt from a black‑box product.
Cleanroom Development Process
Most cleanroom projects we run fall into one of the two scenarios above — either we re‑platform legacy code you own, or we recreate a vendor product you don't. In both cases the focus is re‑engineering, not naive cloning: we restore the business logic, algorithms, architecture and data model, then create a new implementation that you fully control.
- System Observation & Data CollectionUI flows, APIs, databases, traffic, logs and available documentation are analysed with LLM‑assisted tools. Where possible, we also inspect compiled artefacts to understand structure and boundaries.
- Behavioural Twin with LLMsUsing coding agents, we generate an initial behavioural twin of critical components. AI speeds up scaffolding, but engineers remain responsible for architecture and code quality.
- Parity Testing & VerificationAutomated tests compare the new implementation against the original system, exercising typical and edge scenarios. Domain experts are involved in reviewing non‑obvious behaviours.
- Code Cleanliness ReviewWe explicitly check that no proprietary code is copied. The new codebase is independently generated and reviewable, supporting a clean legal position around licences.
- Modernisation & OptimisationOnce parity is established, we can streamline workflows, improve UX, and re‑architect components for scalability, observability and lower TCO.
Managing Risk & Proving ROI
Minimum Downtime Migration
Cleanroom projects are staged and reversible: we run the new system side by side, gradually moving traffic while monitoring behaviour and KPIs to minimise disruption.
ROI That is Easy to Explain
The business case combines licence savings, reduced support and operations overhead, and faster change cycles on a codebase you own. In many cases, payback is measured in months.
Discuss a Cleanroom Project
If you are considering replacing a legacy or proprietary system and want a clean, AI‑assisted path forward, let's talk about what a pilot could look like.