babashka

babashka-example/ calls raylib from babashka over babashka.ffi. Of the four this is the one with no build step at all: a bb.edn, a source file, and bb pacman opens a window.

Declaring the surface

(require '[babashka.ffi :as ffi :refer [defcfn]])
(ffi/load-system-library "raylib")

(defcfn draw-circle "DrawCircle" [:int :int :float :uint] :void)
(defcfn measure-text "MeasureText" [:string :int] :int)
(defcfn key-down?   "IsKeyDown"   [:int] :uint8)

Twenty or so of these cover the whole game. load-system-library does the lookup, and bb doctor prints what it resolved, which is the quickest way to tell a missing raylib from a wrong one:

libraylib  /opt/homebrew/lib/libraylib.dylib

Scalars only

Every parameter above is a scalar, and that is the constraint the port is written around.

A raylib Color is a four-byte struct by value. Rather than pass the struct, rgba packs those same four bytes into one integer:

(defn rgba [r g b a]
  (bit-or r (bit-shift-left g 8) (bit-shift-left b 16) (bit-shift-left a 24)))

Note the order. This packing is the Color struct's own layout in memory, r first at the lowest byte, which is what the ABI would have pushed. It is not the same as raylib's GetColor, which reads 0xRRGGBBAA from the other end. The jank port uses that one instead, and the two look similar enough to swap by accident and produce a picture in the wrong colours.

A C bool comes back as 0 or 1 rather than false/true, so the input predicates wrap it:

(defn down? [k] (pos? (key-down? k)))

Pac-Man is a triangle fan

Pac-Man is emitted through rlgl: rlBegin, a run of rlVertex2f sweeping from the far lip of the mouth round to the near one, then rlEnd.

This page used to say DrawCircleSector was out of reach because its Vector2 centre is by value. That was wrong. babashka.ffi passes structs by value, and binding the call with [:struct [[:x :float] [:y :float]]] and handing it a plain map renders the wedge, confirmed on babashka 1.13.220 on 2026-09-21. The fan is what the original example did and what this port kept, not a limit of the FFI. drawing-pac-man.md has the detail, including why the example calls rlDisableBackfaceCulling once at startup.

What it is good at

Startup. There is no compile and no JVM, so the edit-run loop is about as fast as this gets, which makes it the best of the four for trying something out.

The cost is that the game logic runs on babashka's interpreter rather than compiled code. At this size that is invisible, since the work per frame is a few hundred map updates and the frame is capped at 60 FPS anyway. A heavier simulation would notice.

Credit

This port began from examples/pacman.clj in babashka/ffi, written by Michiel Borkent (@borkdude). That example already had the maze, the ghost personalities and the rlgl fan, so the work here was restructuring it into a namespace with a pure step to match the shape of the other three, plus the unattended run arguments. The other three ports then came off this one, which makes his example the origin of all four.

babashka/ffi is MIT licensed. The notice is reproduced in NOTICE.md at the root of the repository.