README

A CLI Flappy Bird written in Phel (a Lisp that compiles to PHP). Flap through scrolling pipes in your terminal.

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Score: 3     High: 7     (space/up = flap, q = quit)

Play

From a release PHAR (needs only PHP 8.4+):

# download phel-flappybird.phar from the Releases page, then:
php phel-flappybird.phar

From source:

composer install
composer dev          # run straight from source
# or compile an entry point and run it:
composer start        # = composer build && composer play

Controls

Options

Pass key=value arguments to tune the game:

php phel-flappybird.phar width=80 height=30 gap=8 gravity=0.25

--version and --help print info and exit.

Your best score is saved to ~/.phel-flappybird-highscore.

Architecture

Functional core / imperative shell:

• src/core/physics.phel — pure. The whole game is one immutable world map ({:bird :pipes :score :dead?}) advanced by a single step reducer. Randomness is injected by the caller, so step is deterministic and fully unit-tested.
• src/core/render.phel, src/core/input.phel — the effectful edges (terminal drawing via phel-cli-gui, keyboard reading).
• src/game.phel — the loop: read input → step → render → sleep → repeat.

Development

composer test           # run the phel test suite
composer format         # format src + tests
composer build          # compile to out/
composer phar           # build build/out/phel-flappybird.phar
composer ci             # format-check + test + build

Releasing

./tools/release.sh 0.1.0          # validate, build+smoke-test PHAR, tag, GH release
./tools/release.sh --dry-run      # preview without changing anything

License

MIT