HGPPascal — A Modern Pascal Compiler for the Open Source Community

HGPPascal is an open-source Pascal compiler written in Clojure with support for multiple compilation targets including C99, JVM bytecode, and textual Pascal P-Code.

Its goal is to provide a modern, extensible, clean-room implementation inspired by Turbo Pascal while serving as both a practical compiler and a research platform for compiler technology.

Why It Matters

Many classic Pascal compilers are no longer actively developed or are tied to legacy platforms. HGPPascal preserves the language while introducing modern compiler design, automated testing, multiple backends, higher-order functions, object support, optimization passes, and an extensible architecture.

Current Highlights

• C99 backend
• JVM .class generation
• Pascal P-Code backend
• Visitor-based compiler architecture
• Symbol tables and descriptor model
• Turbo Pascal object support
• Units, records, pointers, arrays
• Higher-order functions and closures
• Extensive automated tests

Long-Term Vision

The project aims to deliver:

• Broad Turbo Pascal compatibility
• Native code generation
• LLVM integration
• Debugger support
• Language Server Protocol (LSP)
• IDE tooling
• Better diagnostics
• Rich documentation and educational material

Why Sponsor?

Open-source compiler development is a long-term investment. Sponsorship allows sustained work on compatibility, optimization, documentation, testing, and new backends while keeping the project open and independent.

Whether you contribute financially, write code, improve documentation, or report issues, you are helping preserve and modernize an important programming language ecosystem.

Thank you for supporting HGPPascal.