FlipJump¶
The official FlipJump documentation. FlipJump is a one-instruction esoteric programming language — the only instruction is a;b: flip the bit at address a, then jump to address b. Despite the minimalism, a substantial standard library implements variables, arithmetic, I/O, pointers, and a stack on top of self-modifying code.
🚀 Try FlipJump in your browser — fj.tomhe.app
New in 1.5.0
⚡ Native interpreter engine — ~300M FlipJump ops/second, prebuilt in the wheels and used automatically. Details →
🖥️ Interactive IO —
fj --run prog.fjm --io pcopens a window with a live keyboard and a 256-color screen. Details →🐞 CLI debugger — breakpoints, single-step/skip, and memory/variable inspection. Details →
📚 New STL macros —
hex.abs,hex.fill_bytes,hex.copy_bytes. Standard library →
Where to start¶
Install, run “Hello World”, and learn the program skeleton.
The single instruction, expression syntax, macros, namespaces, I/O.
Auto-generated reference for every macro in flipjump/stl/.
Ten short recipes: hello world, echo, decimal print, branches, loops, swap, add, function call.
Hello World, prime sieve, calculator, quine — annotated.
The browser IDE, the c2fj (C) and bf2fj (Brainfuck) compilers, the Claude skill, editor highlighting for VS Code & JetBrains, a Ghidra extension for .fjm binaries, and the upstream repo & esolangs references.
External links¶
The upstream
flip-jumprepository for the language implementation, examples, and tests.The esolangs.org wiki entry for background and design commentary.
IDE plugins¶
Get .fj syntax highlighting in your editor — the same fj-dark colours as the browser IDE and these docs:
VS Code — FlipJump on the VS Code Marketplace.
JetBrains IDEs (IntelliJ IDEA, PyCharm, CLion, …) — FlipJump on the JetBrains Marketplace.
See Editor syntax highlighting for install details.