A code-first environment for building and testing finite automata and Turing machines in TypeScript
No setup required: comptheory.tools
NFA & DFA — Define machines with a fluent TypeScript API. Errors surface at build time. Convert any NFA to an equivalent DFA via subset construction, with human-readable state names preserved.
PDA — Pushdown automata with full stack visualization. Watch each push and pop in real time as your machine processes input.
Turing machines — Single and multitape machines with a step-through visualizer that highlights the active transition at every step.
Thompson's construction — Build NFAs from regular expressions using a stack-based API mirroring union, concatenation, and Kleene star.
Pair any machine with a test suite and Delta runs them all inline — correctness is verifiable, not just visually convincing.
Every machine encodes into a URL. No accounts, no exports, no hoops.
git clone https://github.com/sydrinea/delta
cd delta
pnpm install
pnpm run dev
@delta/buildis not yet published to npm. It's available as a workspace package within this monorepo.