keydr

A terminal typing tutor with adaptive learning, a skill-tree progression system, and live statistics — built in Rust on ratatui. Heavily inspired by keybr.com, extended for code practice and the terminal.

Warning: still very much a WIP and is heavily vibe-coded so there may be bugs. Backwards compatibility is not guaranteed in this phase of development.

Screenshots

What makes it different

Most TUI typing apps either drop you on a fixed word list or randomize from a dictionary. keydr keeps a model of your typing: per-key timing, per-bigram error rates, and a confidence score for every key on the keyboard. The text it generates for you is shaped by that model — words bias toward the keys you're slowest at, new keys unlock only when the keys you already have are solid, and the difficulty grows with you.

Features

Adaptive engine

• Per-key confidence model. Every keystroke updates an exponential moving average of your per-key time. Your confidence for a key is your target speed divided by that filtered time — a key with confidence >= 1.0 is at or above your target speed.
• Gradual letter unlocking. You start with 6 letters in English-frequency order (e t a o i n …). A new letter unlocks only when every letter you already have is confident, so you're never thrown into the full alphabet at once.
• Focused-key biasing. Whichever included key has the lowest confidence becomes your "focused" key. The generator searches its Markov chain for states containing the focused letter and starts pseudo-words from there, so drills naturally pile up practice on your weak spots.
• Phonetic pseudo-word generation. Words are generated from a Markov transition table (the same approach as keybr) so they're pronounceable and language-shaped, not random consonant noise.
• N-gram error tracking. Beyond single keys, keydr tracks bigrams and trigrams with Laplace-smoothed error rates and a redundancy formula that separates genuine transition difficulties (e.g. awkward same-finger bigrams) from errors that are just proxies for a single weak key. Hard bigrams get folded into drill selection.

Skill tree

Once you've mastered the lowercase alphabet, you don't just keep grinding prose — five sibling branches unlock at once and you pick what to drill next:

• Capitals (A–Z, 3 levels) — sentence-start and proper-noun rules
• Numbers (0–9, 2 levels)
• Prose punctuation (. , ' " ? ! …, 3 levels)
• Whitespace (Tab, Enter, …, 2 levels)
• Code symbols ({ } [ ] ( ) ; : = + - * / …, 4 levels)

Each branch tracks its own current level and its own focused key. You can have multiple branches "in progress" at once, and drills can be scoped globally (everything you've unlocked) or to a single branch.

Three drill modes

• Adaptive — the default. Generated text from the phonetic model, biased by your skill-tree scope and focused key.
• Code — language-specific syntax practice. Bundled snippets for Rust, Python, JavaScript, and Go, with optional opt-in downloads of real code samples from GitHub for more variety. Configurable per-language, with an onboarding screen on first use and a download progress screen.
• Passage — type real prose from public-domain books (Project Gutenberg). Opt-in downloads, configurable paragraphs-per-book limit, falls back to bundled content when offline.

Statistics dashboard

A multi-tab dashboard with everything the engine has learned about you:

• Dashboard — current WPM, accuracy, confident-key count, level/streak
• History — recent drills with WPM/accuracy
• Activity — a GitHub-style heatmap of drilling activity over time
• Accuracy — per-key accuracy heatmap laid out on the keyboard
• Timing — per-key timing heatmap
• N-grams — your worst bigrams/trigrams, redundancy scores, watchlist of emerging weak transitions, and what's currently driving drill focus

Visual keyboard

A live keyboard diagram colors each key by the finger that should press it, highlights your focused key, and (in terminals that support the Kitty keyboard protocol) lights up modifier keys as you press them. A separate Keyboard Explorer screen lets you click around the layout to inspect any key's stats.

Theming

14 built-in themes: Catppuccin (Mocha/Latte), Dracula, Gruvbox (Dark/Darkest), Kanagawa (Wave/Dragon/Lotus), Nord, One Dark, Solarized Dark, Tokyo Night, Farout, plus an ANSI-safe terminal-default that respects your terminal's own colors.

Internationalization

• UI translated into 21 languages (en, de, es, fr, it, pt, nl, sv, da, nb, fi, pl, cs, ro, hr, hu, lt, lv, sl, et, tr).
• Dictionaries for the same 21 languages, sourced from keybr-content-words.
• Keyboard layout profiles: QWERTY, Dvorak, Colemak, German QWERTZ, French AZERTY — with per-layout finger maps so the diagram stays accurate.
• Unicode-normalized (NFC) input matching, so composed and decomposed forms of accented characters compare equal.

Import / export

Back up everything — config, profile, key stats, ranked stats, drill history — to a single timestamped JSON file from the Settings page, and restore it on another machine. Machine-local paths (download directories) are preserved from the target machine on import. Versioned format with a clear error if schemas don't match.

Other niceties

• Atomic JSON writes (temp file → fsync → rename) so a crash mid-save can't corrupt your stats.
• Auto-continue between drills with a brief input lock so a trailing keystroke doesn't start the next drill prematurely.
• Mouse support for menus, tabs, and the keyboard explorer.

Build and run

keydr is a regular Cargo project. You need a recent Rust toolchain (Rust edition 2024, i.e. a 2026-era stable compiler).

git clone <repo-url> keydr
cd keydr
cargo run --release

Or build once and run the binary:

cargo build --release
./target/release/keydr

CLI flags

keydr [--theme <name>] [--layout <layout>] [--words <n>]

• --theme, -t — pick a theme by name for this run (e.g. dracula, nord, catppuccin-mocha)
• --layout, -l — pick a keyboard layout: qwerty, dvorak, colemak, de_qwertz, fr_azerty
• --words, -w — number of words per drill

Everything else is set from inside the app, on the Settings screen.

Features

The network Cargo feature (on by default) pulls in reqwest and enables the optional GitHub code download and Project Gutenberg passage download flows. To build a fully offline binary:

cargo build --release --no-default-features

Files on disk

• Config: ~/.config/keydr/config.toml
• Profile, key stats, drill history: ~/.local/share/keydr/*.json
• Downloaded passages: ~/.local/share/keydr/passages/
• Downloaded code samples: ~/.local/share/keydr/code/

(dirs is used to resolve these, so the exact paths follow XDG/macOS/Windows conventions on your platform.)

Tests and benchmarks

cargo test
cargo bench       # n-gram benchmarks in benches/

Terminal requirements

keydr works in any reasonably modern terminal. For the best experience — modifier-key highlighting on the keyboard diagram, unambiguous key disambiguation, and per-key release events — use a terminal that supports the Kitty keyboard protocol (Kitty, WezTerm, foot, recent Ghostty, recent Alacritty). keydr falls back gracefully on terminals that don't (tmux, mosh, SSH to older hosts) using timer-based heuristics.

A true-color terminal is recommended so the bundled themes render as intended; the terminal-default theme is provided for ANSI-only setups.

License and attribution

keydr is licensed under the GNU Affero General Public License v3.0 only (AGPL-3.0-only) — see LICENSE.

It incorporates content and ideas from keybr.com (dictionaries, the core adaptive algorithm). See THIRD_PARTY_NOTICES.md for attribution and docs/license-compliance.md for the compliance process.