https://mecanik.dev/en/tags/cobol-migration/Recent content in COBOL Migration on [ MECANIK DEV ]Hugo -- gohugo.ioenCopyright © 2020-{year} by [ MECANIK DEV ]. All Rights Reserved.Mon, 03 Aug 2026 07:00:00 +0100https://mecanik.dev/en/posts/cobol-modernisation-services-choosing-a-vendor/Mon, 03 Aug 2026 07:00:00 +0100https://mecanik.dev/en/posts/cobol-modernisation-services-choosing-a-vendor/Buying COBOL modernisation services is unlike buying any other kind of software work. The system in question has been running for thirty or forty years, nobody currently employed fully understands it, and the consequences of getting it wrong are measured in regulatory reporting failures rather than missed sprints. Meanwhile the proposals on your desk all promise the same outcome at wildly different prices. This guide sets out what a serious engagement actually contains, how the vendor types differ, and which questions separate a bid built on evidence from one built on optimism.https://mecanik.dev/en/posts/mainframe-migration-tools-what-works/Sat, 01 Aug 2026 07:00:00 +0100https://mecanik.dev/en/posts/mainframe-migration-tools-what-works/Every mainframe migration begins with someone searching for mainframe migration tools, and every vendor demonstration that follows looks remarkably convincing. A few thousand lines of COBOL go in, readable Java comes out, the test suite passes, and the slide deck promises seventy or eighty per cent automation. The demonstration is usually honest. It is also usually run against code that behaves nothing like yours. This guide describes the categories of tooling that actually exist, what each one genuinely does well, and the specific places where each tends to fail on real workloads.https://mecanik.dev/en/posts/cobol-migration-cost-timeline-and-risk-uk-guide/Sun, 05 Jul 2026 19:00:00 +0100https://mecanik.dev/en/posts/cobol-migration-cost-timeline-and-risk-uk-guide/“How much will it cost to move off COBOL?” is the first question every board asks, and the honest answer is that it depends on more than the size of the codebase. This guide breaks down what actually drives the cost of a COBOL migration in the UK, realistic budget and timeline ranges, and the risks that turn a well-planned project into an overrun. TL;DR A mid-size UK COBOL migration typically costs £200,000 to £800,000 and takes one to two years; full mainframe decommissions run into the millions and multiple years Cost is driven far more by codebase complexity, undocumented business logic, and data access redesign than by raw line count The choice of target language and migration approach materially changes the budget The most common reason projects overrun is underestimating scope, especially undocumented business rules and the data access layer What Actually Drives COBOL Migration CostLine count is the headline number, but it is a weak predictor on its own.https://mecanik.dev/en/posts/cobol-to-rust-migration-a-uk-enterprise-guide/Sun, 05 Jul 2026 07:00:00 +0100https://mecanik.dev/en/posts/cobol-to-rust-migration-a-uk-enterprise-guide/Rust is an increasingly popular COBOL migration target for organisations that want both memory safety and high performance without a garbage collector. For safety-critical and performance-sensitive systems, its guarantees are compelling: whole classes of memory bugs are caught at compile time, and the resulting binaries are fast and predictable. Rust is also the most demanding target on this list, because its ownership and borrowing model is fundamentally different from COBOL’s flat data model.https://mecanik.dev/en/posts/cobol-to-go-migration-a-uk-enterprise-guide/Sat, 04 Jul 2026 19:00:00 +0100https://mecanik.dev/en/posts/cobol-to-go-migration-a-uk-enterprise-guide/Go is a pragmatic COBOL migration target when simplicity, fast builds, and easy deployment matter more than a large enterprise framework ecosystem. It compiles to a single static binary with no runtime dependencies, it runs anywhere, and its built-in concurrency model is a natural fit for modernising COBOL batch processing into parallel workloads. This guide explains what a COBOL to Go migration actually involves, the approaches available to UK enterprises, what it costs, and the one precision issue you must plan for up front.https://mecanik.dev/en/posts/cobol-to-java-migration-a-uk-enterprise-guide/Sat, 04 Jul 2026 07:00:00 +0100https://mecanik.dev/en/posts/cobol-to-java-migration-a-uk-enterprise-guide/Java is the most common destination for enterprise COBOL migration, and it is easy to see why. It is mature, strongly typed, backed by an enormous library ecosystem, and supported by one of the deepest developer hiring pools in the UK. For organisations running critical COBOL on IBM mainframes, Java offers a route to a modern platform without abandoning the enterprise-grade rigour those systems demand. This guide explains what a COBOL to Java migration actually involves, the approaches available to UK enterprises, what it costs, and how to manage the risk.https://mecanik.dev/en/posts/cobol-to-csharp-migration-a-uk-enterprise-guide/Fri, 03 Jul 2026 19:00:00 +0100https://mecanik.dev/en/posts/cobol-to-csharp-migration-a-uk-enterprise-guide/COBOL still underpins a vast amount of the software running in UK banks, insurers, public sector bodies, and large retailers. Much of it processes money, and much of it has been running since long before the developers maintaining it today joined the organisation. As COBOL expertise retires out of the workforce, the pressure to modernise grows every year, and a COBOL to C# migration is one of the routes UK organisations most often consider.https://mecanik.dev/en/posts/cobol-to-python-migration-a-uk-enterprise-guide/Sun, 21 Jun 2026 07:00:00 +0100https://mecanik.dev/en/posts/cobol-to-python-migration-a-uk-enterprise-guide/COBOL powers an estimated hundreds of billions of lines of code still running in global financial systems, government infrastructure, and enterprise backends. In the UK, many of those systems are running in banks, insurance companies, public sector organisations, and large retailers. The developers who wrote them are retiring. The organisations running them are feeling the pressure. Python has become the migration target of choice for most COBOL modernisation projects, and for good reason.