Rust engine • iOS • TUI • WASM

Sudoku with teeth.

Ukodus is a Sudoku app built on a shared Rust core: unique puzzles, human-style difficulty ratings, and fast hints. No trackers, no analytics, no weird “engagement” math.

Unique solutions

Human difficulty model

Local data by default

Same engine everywhere

Download on the App Store Watch demos Source + builds How difficulty works

Built like a tool, not a trap.

Fast, readable, and honest: if a puzzle is ambiguous, the generator throws it away and tries again.

Local-first

No analytics. No trackers. Your progress stays on-device (optional Game Center / iCloud).

Difficulty you can feel

The Rust solver simulates human techniques to assign a rating. Generation retries until it matches the requested level.

One engine, many shells

The same core powers iOS, a terminal UI, and a WASM build. Same puzzles. Same rules. Same difficulty model.

Demos

More builds that share the same generator and solver.

Terminal UI: keyboard-driven, instant feedback, same Rust core.

cargo run -p sudoku-tui --bin sudoku

wasm-pack build crates/sudoku-wasm --target web --out-dir crates/sudoku-wasm/www/pkg --release
cd crates/sudoku-wasm/www
python3 serve.py 8080

Engine Notes (Rust)

Puzzle generation starts with a full solution, removes givens while preserving uniqueness, then rates the result using a technique-based solver. If the rating is wrong, generation retries.

Generate
  1) Create a fully solved grid
  2) Remove givens (often in symmetric pairs)
  3) After each removal: verify exactly one solution exists
  4) Run the human-style solver to rate difficulty
  5) If the rating doesn't match the requested level: retry

Difficulty system Generator source Solver source