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Legacy modernization

Move off the old system, without losing a thing, or stopping the business.

Your legacy system holds years of data, millions of documents, and the operations your business runs on. Replacing it is daunting, because the real risk isn't the new technology, it's losing that data or breaking what works. We modernise legacy systems in safe, staged steps, migrating every record intact and keeping the business running the whole way through.

2–4wks
to first working software
1–2wks
to project kickoff
100%
code & IP ownership
6–10yrs
average engineering experience

Legacy modernization services

Every modernization starts with understanding what you have, then choosing the safest path forward. Pick a capability to see how we approach it.

Before anything moves, we map what you actually have: the code, the data, the dependencies, and the risks hiding in a system no one fully documented. You get a clear picture and an honest recommendation before a single decision is made.

How we help

We analyse the codebase and data, surface the risks and the quick wins, and give you a staged plan tied to business priorities, not a black-box proposal.

This is the part that keeps people up at night: moving millions of documents and records without losing, corrupting, or mismatching a single one. We migrate your data in validated stages, verifying integrity at every step, so what comes out the other side is exactly what went in.

How we help

Staged migration with reconciliation and validation checks at each phase, plus full audit trails, so you can prove nothing was lost.

Sometimes the fastest, lowest-risk first step is moving the application as-is onto modern infrastructure, off ageing hardware, without changing the code yet. It buys stability and time.

How we help

We move workloads to modern cloud or infrastructure with minimal downtime, so you get off failing hardware quickly and modernise the rest at your own pace.

Legacy code accumulates decades of shortcuts, dead logic, and security holes. We clean it up, restructure it, and bring it to modern standards, so it's maintainable, secure, and cheaper to run, without changing what it does for the business.

How we help

We remove dead and risky code, add tests, and modernise the codebase in reviewable steps, cutting technical debt without breaking behaviour.

When the old architecture can't scale or adapt, we redesign it for the cloud, breaking monoliths into services where it helps, so the system becomes flexible, scalable, and ready for what's next.

How we help

We re-architect incrementally, moving in reversible waves, so the business keeps running while the foundation is rebuilt underneath it.

A modernised system has to talk to everything else you run. We connect it to modern APIs and services, so the old capabilities become available to new tools, and your data flows where it's needed.

How we help

We build clean, secure API layers so legacy functionality and data plug into your modern stack without a rewrite.

A system no one understands is a system no one can safely change. We document what was undocumented and remove what's obsolete, so your team can actually own and evolve the result.

How we help

We produce clear documentation and knowledge transfer, so the modernised system isn't another black box.

Once you're safely on the new system, the old one has to be retired properly, with historical data archived securely for compliance and reference, and the maintenance cost switched off.

How we help

We archive historical data securely and decommission the old system cleanly, cutting cost and risk without losing anything you're required to keep.

Systems we've modernised

View all case studies

The stack we build with

Standard, proven tooling for safe migration and modernization, chosen to fit your system, not a fixed template. Pick an area to see what we reach for.

Every safe migration begins with an honest picture of what you actually have. We use static analysis, quality scanners, and dependency mapping to read the codebase, expose the risky corners no one documented, and trace how each part connects, so the plan we recommend is grounded in evidence rather than guesswork.

Static analysis
Code quality scanners
Dependency mapping
Test coverage

When logic has to be rebuilt or wrapped, we do it on proven, well-supported platforms your team can own for years, not a niche framework that becomes tomorrow's legacy. We match the language and stack to your people and your system, so the modernised core stays maintainable long after we hand it over.

Python
Django
FastAPI
Node.js
.NET
Java

This is the part that keeps people up at night, and where we're most careful. We move data in validated stages, reconciling record counts and checking integrity at every step, with full audit trails, so millions of documents and records arrive exactly as they left, and you can prove nothing was lost or altered.

PostgreSQL
MySQL
MongoDB
ETL & migration tooling
Reconciliation

Ageing hardware is a risk that only grows. We move workloads onto modern cloud infrastructure that's observable, resilient, and cost-predictable, defined in code so environments are repeatable and easy to roll back. You get off failing servers quickly and gain the scale and monitoring the old setup never offered.

AWS
Azure
Docker
Kubernetes
Terraform

A modernised system rarely lives alone, it has to keep talking to everything else you run. We build clean, secure API layers and event flows that expose old capabilities to new tools and let old and new run side by side during cutover, so data keeps moving where it's needed without a risky all-at-once switch.

REST
GraphQL
Message queues
Webhooks

Staged, reversible migration only works if each step can ship and roll back safely. We put automated pipelines and test suites around the work so every wave is built, tested, and deployed the same way, with a fast path back if something looks wrong, which is what keeps a phased cutover low-drama instead of high-stakes.

GitHub Actions
Jenkins
Automated testing
Staged rollout

Migration is exactly when sensitive data is most exposed, so we protect it in transit and at rest, enforce least-privilege access, and log every action for a full audit trail. We build to and align with the standards your data requires, such as GDPR and HIPAA, so the move hardens your security posture rather than putting it at risk.

Encryption
Access control
Audit logging
GDPR / HIPAA aligned

Our legacy modernization process

Nine steps, run in order and always phased, reversible, and low-risk, from first assessment through to decommissioning the old system and handing over the new one. The business keeps running the whole way through.

01

Discovery & assessment

We map the code, data, dependencies, and risks, and document what was undocumented, so decisions are made on facts, not guesses.

02

Migration strategy & prioritisation

We recommend the lowest-risk path, what to reuse, rehost, refactor, or rebuild, sequenced around business priorities.

03

Data migration plan & validation

We design how every record moves, with reconciliation and integrity checks defined up front, so nothing is left to chance.

04

Staged migration / rebuild

We move in small, reversible waves, never a big bang, so each step is verified before the next begins.

05

Testing & reconciliation

We test behaviour and reconcile migrated data against the source, proving that what came out matches what went in.

06

Phased cutover

We switch over in phases, often running old and new in parallel, so the business keeps running with a safe path back if needed.

07

Monitor & optimise

After each phase we monitor performance, errors, and data integrity, and tune before moving on.

08

Decommission & archive

Once you're safely on the new system, we archive historical data securely for compliance and retire the old system cleanly.

09

Knowledge transfer

We hand over clear documentation and walk your team through the result, so the modernised system is genuinely yours to own.

Legacy experts, AI-augmented

These are the AI coding tools our engineers use to ship faster and keep code clean, distinct from the AI systems we design and build for you.

Claude CodeGitHub CopilotCodexCursorReplitGeminiOllamaWindsurf

We use these tools inside strict guardrails, every line is reviewed by a person. See how we build →

1

Senior Legacy engineers

Engineers with real, hands-on legacy experience who take ownership of the work, not juniors learning on your budget.

2

Production-grade delivery

We take work from prototype to production, with testing, monitoring, and clean handover, not demos that stall after the pitch.

3

Security & compliance

Safeguards from day one. We build to and align with the standards regulated industries expect, including HIPAA, SOC 2, and ISO 27001.

We've modernised systems across logistics, healthcare, and more.

See how we approach your industry
Engagement

How you'd work with us on Legacy

Pick the level of ownership that suits you. We shape the engagement around your goals.

1

Staff augmentation

Add senior Legacy engineers to a team you already have.

2

Dedicated team

A committed Legacy team that runs like your own.

3

Full delivery

Hand over the build and we deliver it end to end.

Explore engagement models

Legacy FAQ

Stuck on a legacy system you can't afford to lose, or to keep?

Tell us what you're running, and we'll tell you honestly the safest way to modernise it.

Book a discovery call