Legacy Software Modernization Services
Your software still runs the business, but it sits on a stack nobody wants to touch: an end-of-life framework, a database nobody understands, a developer who left. We modernize it in stages while it keeps running, starting with a fixed-price audit, and we publish our prices.
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What is legacy software modernization?
Legacy software modernization is the work of moving an application that still matters to the business off technology that has become a liability, without losing the business rules it encodes. That can mean upgrading the framework, replacing the database layer, rebuilding the interface, or rewriting the system piece by piece, while the people who use it every day keep working.
The hard part is rarely the new technology. It is that the old system is the only accurate description of how the company actually works, with years of exceptions buried in it. A modernization that loses those rules is a regression, however modern the result looks.
Signs your software needs modernizing
- Its framework or language version is out of support, so security fixes have stopped. PHP 8.2 loses security support at the end of 2026, Symfony 6.4 loses bug fixes in November 2026, and AngularJS has had no support since January 2022.
- Nobody can change it safely. Every fix breaks something else, there are no tests, and the one person who understood it has left.
- You cannot hire for it. Developers who know the stack are rare, expensive, or not interested.
- It cannot connect to anything: no API, so data moves by export, copy and paste.
- Hosting it is a risk in itself: one server, configured by hand, that nobody dares restart.
The options, and when each one fits
There is no single right answer. The choice depends on how sound the business logic is and how bad the technology has become.
| Option | What it means | When it fits |
|---|---|---|
| Rehost | Move the application as it is onto managed, reproducible infrastructure. | The code is acceptable but the hosting is the risk. Fast and cheap, fixes nothing in the code. |
| Refactor and upgrade | Keep the codebase; add tests, upgrade the framework and dependencies, clean up the worst parts. | The structure is sound and the stack is merely out of date. Usually the best value. |
| Incremental rewrite | Rebuild one module at a time on a modern stack, routing each part to the new system as it is ready. | The code is beyond saving but the business cannot stop. Slower, much safer than a big-bang rewrite. |
| Replace with a product | Retire the application and move to an off-the-shelf tool. | The process is standard and a mature product covers it. We will tell you when this is the answer. |
The option we steer people away from is the big-bang rewrite: freeze the old system, rebuild everything, switch over on one weekend. It is the most expensive way to discover which business rules nobody wrote down.
How we modernize legacy software
The system keeps running at every step.
- 1
Fixed-price audit
We read the code, the database, the infrastructure and the incident history, and recommend one of the options above with a costed plan. You own the report whether or not you continue with us.
What the code audit covers → - 2
Stabilize
Version control, repeatable deployment, backups, monitoring and recovered access, before any code changes. This alone removes most of the risk.
- 3
Modernize in slices
Tests around the parts that matter, then upgrades or rewrites module by module, each one shipped to production before the next begins.
- 4
Run it, or hand it over
We host and maintain the modernized system, or hand it to your team with the infrastructure written as code and the business rules documented.
How much does legacy software modernization cost?
Our published prices, in US dollars. The audit is the only fixed figure, because nobody can price a modernization honestly before reading the code.
| Stage | Price | What you get |
|---|---|---|
| Code audit | $2,900, fixed | What is sound, what is not, the recommended option, and a costed plan. |
| One module modernized | $5,000 to $18,000 | One part of the system upgraded or rewritten, tested and in production. |
| Whole application | $18,000 to $45,000+ | The full modernization, delivered module by module against agreed milestones. |
| Maintenance afterwards | from about $470 per month | Hosting, monitoring, dependency upgrades and a monthly allocation of changes. |
What moves the price: how much test coverage exists (usually none), how far the stack is behind, and how much data has to move. The audit is what turns those unknowns into a number.
How to choose a legacy modernization partner
- Do they start by reading your code, before quoting the modernization? A quote without an audit is a guess you will pay for later.
- Do they recommend the cheapest option that solves the problem, including leaving parts alone?
- How do they keep the business running during the work? You want module-by-module delivery, not a cutover weekend.
- How do they capture the business rules hidden in the old code before they rewrite it?
- Who runs the modernized system afterwards, and do you own the code and the infrastructure configuration?
Frequently asked questions
What is legacy software modernization?
Legacy software modernization is moving an application that still matters to the business off technology that has become a liability, such as an unsupported framework, an unmaintainable codebase or fragile hosting, while keeping the business rules it encodes and keeping it running for the people who depend on it.
How much does legacy software modernization cost?
At Reflekt Lab, the code audit that comes first is a fixed $2,900. Modernizing one module typically costs $5,000 to $18,000, and a whole application $18,000 to $45,000 or more, delivered in stages. Maintenance afterwards starts around $470 per month.
Should we rewrite or refactor our legacy software?
Refactor when the structure of the code is sound and only the stack is out of date: it is usually the best value. Rewrite, module by module, when the code is beyond saving. Avoid a big-bang rewrite that freezes the old system and switches over on one date; it is the riskiest and most expensive option.
Can you modernize software while we keep using it?
Yes, and that is the default. We stabilize the existing system first, then modernize one module at a time, each one shipped to production before the next begins, so the business never stops.
Which legacy technologies do you work with?
We audit and modernize business applications built on older PHP and Symfony versions, Node.js, AngularJS-era front ends, and Excel or VBA tools that grew into systems. We modernize toward Go, Python, TypeScript and React with PostgreSQL, deployed as code. If your stack falls outside what we can support, we say so before accepting the engagement.
What is the difference between legacy modernization and a software project rescue?
A rescue takes over a project whose developer has gone, whatever its age. Modernization moves a system off technology that has become a liability, even if the original team is still around. They often overlap, and both start with the same code audit.
Tell us what your old system runs
A free 30-minute call. Describe the application, its stack and what worries you about it, and leave with a view on which option fits and what the audit would cover.
