Polyglot Corner: Bouncing Ball, Three Lisps

You just built a bouncing ball in JVM Clojure (exercises/phase_1/bouncing_ball.clj). Here's the exact same idea, already built, in the other Lisp dialects this course's sibling repos use. You don't need to understand every line yet - just notice how much of the shape survives the jump: init/tick/draw, an immutable world value, the same raylib calls underneath.

Jolt (native Clojure, Chez Scheme, no JVM)

bounce.clj in b12n-raylib-jlt: a bouncing ball with IsKeyPressed-driven pause and an on-screen DrawFPS counter. Jolt calls raylib with zero C shim code at all, it exploits real ABI facts about how C passes small structs (you'll learn exactly how in Phase 3). Run it yourself if you have Jolt installed: cd b12n-raylib-jlt && bb bouncing-ball.

jank (native Clojure, C++/LLVM, no JVM)

b12n-raylib-jnk's bouncing-ball port, same idea, a completely different FFI philosophy: jank draws the line at the value, not the call, a native raylib value can't leave the function that created it. You'll build this same ball again, deliberately, in Phase 3's comparative module.

What's identical, what's not

• Identical: the shape of the program. Every one of these has an init, something that runs every frame to move the ball, something that draws it, and a loop that ties them together.
• Not identical: how each dialect talks to raylib's C code underneath. JVM Clojure (what you're using) goes through JDK's Panama FFI. Jolt and jank each have their own answer, with real trade-offs - that's the whole subject of Phase 3.

Next

Phase 2: Arcade Classics: time to build something with an actual win/lose condition.