The SedaiBasic Interpreter Performance marks a bold step in the evolution of modern retro programming. Created by Maurizio Cammalleri, SedaiBasic is a language interpreter written in Free Pascal, with its first supported language being Commodore BASIC V7.0.
What makes SedaiBasic remarkable is its balance between authenticity and modern efficiency. The console now mirrors the look of a Commodore 128 while adapting automatically to your monitor’s resolution. It maintains the original aspect ratio and uses an 8×8 pixel TrueType font, scaled cleanly for sharp results on any display. It even supports resolutions up to 8K when compatible hardware is available.
Speed That Surprises
Performance has always been a key focus for Cammalleri, and the SedaiBasic Interpreter Performance speaks for itself. The interpreter now executes the Sieve of Eratosthenes test with n = 10,000 in under 140 milliseconds. That puts it ahead of many pure interpreters, including some written in C.
Behind the scenes, the optimization work shows real technical depth. The executor has been refined for efficiency, and Cammalleri continues to push performance further with each build. This is not just a nostalgic project—it’s a modern rethinking of what BASIC can achieve when coupled with smart engineering.
A Virtual Machine with Modern Power
The next phase of SedaiBasic introduces a virtual machine, also coded in Free Pascal. Early benchmarks using the same Sieve test delivered results around 5 milliseconds, with a best time of 4.75 milliseconds. On an older i7-3630QM system, that performance is impressive.
The virtual machine is fully register-based, borrowing ideas from high-performance engines such as Python and JavaScript’s V8. In fact, on the same test machine, Python 3.13.5 completes the benchmark in roughly 2 milliseconds—putting SedaiBasic surprisingly close for a new project.
Once the VM is finalized, Cammalleri plans to introduce a JIT compiler that could rival JavaScript V8 performance. This feature would take the SedaiBasic Interpreter Performance to a new level of speed and responsiveness, closing the gap between interpreted and compiled code.
Looking Ahead
Encouraged by the success of his lexer, parser, executor, and VM, Cammalleri is now working on a Visual Basic 6-compatible dialect. This version will be fully object-oriented, expanding SedaiBasic’s reach to developers who prefer structured, modern coding approaches while keeping the familiar BASIC syntax alive.
The project will soon release binaries and test programs under the GNU GPL v3 license, allowing anyone to verify its performance firsthand. Cammalleri welcomes users to experiment, benchmark, and share results to help refine this growing interpreter ecosystem.
SedaiBasic isn’t just a tribute to the past—it’s proof that classic languages can evolve without losing their charm or speed.
