Bring your Delphi, Pascal or old Java desktop application to the web without a rewrite.
If your business still depends on a legacy desktop system, I can help you get that existing logic running in the browser with familiar workflows and a transparent migration.
The situation
- Your core system was written 10, 15 or 20 years ago in Delphi, Pascal or Java. It works reliably and your staff know it inside out.
- The catch is that it only runs on Windows desktops. Remote staff and Mac users can't easily use it, and nobody wants to touch the old build machine in case it breaks.
- Agencies quote R500k+ and nine months to rewrite it from scratch, which almost always means losing edge-case rules you spent years refining and retraining the whole team.
Preserve the business logic, move the runtime to the browser
Having worked with Delphi, Object Pascal and Java for over two decades, I know how much hard-won domain knowledge lives inside older desktop codebases. Rather than throwing that away and rewriting everything in a trendy new framework, I preserve your core Pascal, Delphi or Java business logic and compile it to run in the browser using WebAssembly.
To make this practical, I built WasmPascal, a Pascal-to-WebAssembly compiler that runs directly in the browser, alongside WasmCoffee for Java-style code targeting Wasm-GC.
- Your business rules stay intact. Years of domain logic, calculations and edge cases don't get lost in translation by a team that doesn't know your industry.
- It runs in any modern browser. Chrome, Edge, Safari and Firefox on Windows, macOS, Linux or tablets, with no local runtime or DLL headaches.
- Fast and lightweight to host. WebAssembly runs at near-native speed in the client browser, keeping your server hosting simple and affordable.
How the engagement works
- 1. Rescue Audit (1 week, R35,000 fixed, credited to the build). I review your codebase, database and workflows. You get a plain-English report covering what can be lifted as-is, what needs a thin wrapper, what the browser UI will look like, and a fixed price for the build. There is no obligation to continue.
- 2. Browser Build (4 to 8 weeks). I bring your core logic across to WebAssembly, build the browser interface around it, and connect the database via a dedicated API. You can run and test it side-by-side with your desktop system so there is plenty of testing opportunity.
- 3. Handover & Optional Support. You receive the full source code, build scripts and documentation. I can stay on a small monthly retainer for ongoing maintenance and small features, or hand everything over cleanly to your team.
- WasmPascal: My Pascal-to-WebAssembly compiler running live in the browser. It compiles Pascal source directly to WebAssembly bytecode client-side.
WasmPascalLarge CSV benchmark post - My Paddock: A simulation written in Pascal and compiled to WebAssembly with WasmPascal, running as a standalone browser application.
My Paddock - Wartech / Harvester Wars IV / Destroids: Real-time strategy, physics and canvas rendering at 60fps in the browser with no bloated web framework.
Harvester Wars IVWartech RTSDestroids - Batchiness: My open-source Canvas 2D batching library that reduces WASM-to-JS boundary crossings to one call per frame so data-heavy screens stay responsive.
Batchiness on GitHub
Is this a good fit?
Good fit if- You have a working Delphi, Pascal or Java desktop application that your business relies on
- You know how it should work and want to keep its proven rules and workflows
- You need browser access for remote staff, Mac users or clients
- You want to work directly with an experienced developer rather than an agency sales team
- You want to retire the old system completely and build a new product from scratch (see my Startup MVP offer instead)
- Your application is already on the web and simply struggling with slow rendering or large datasets (see Performance Audit + Fix)
- You are looking for an investor or equity partner rather than a contractor
Pricing
Prices below are indicative; we agree on a firm fixed price in writing before any work starts.
- Rescue Audit: R35,000 fixed for the codebase assessment, feasibility report and fixed-price build quote (credited if we proceed).
- Rescue Build: From R175,000 fixed price agreed after the audit, paid against clear milestones.
- Monthly Care: From R8,000/month for maintenance, small features and hosting assistance. Cancel anytime.
Frequently asked questions
Will my staff need retraining?
Most likely, yes, I am not going to lie about it. I try to keep the screens and workflows familiar, but the web is a different beast with its own limits and paradigms, so some things will change. The goal is the same application running in a browser, not a new system everyone has to learn from scratch, so we'll strive to keep the changes as small as possible and document them properly. At the very least, you are not starting from scratch.
What about my database?
We keep it where we can, or we set up a new database if that's the best option. If I can connect the browser application to your existing database via an API, we go that route. If not, I help you migrate to PostgreSQL or SQLite if that's the better play. Your data stays yours of course, and we'll figure out what's best for your business once we know what else needs to feed from the database.
Is WebAssembly safe and future-proof?
Yes. WebAssembly is a W3C web standard supported by every modern browser and backed by Google, Mozilla, Apple and Microsoft. It is not a passing framework that will be abandoned next year.
Who owns the code?
You do, 100%. Once payment is settled, you get the full source code, build instructions and documentation.
Let's see if your application is a candidate
.pas or .java files, your Delphi project layout, or simply a few screenshots of the screens, and we can figure out whether a browser build makes sense for your business.
Book a 30-min Legacy Rescue Call