Tail Recursion

You never steer.

There are no arrow keys. Your snake stands still until the program you built tells it to move — and then it does exactly what you wrote, including the part you got wrong.

Tail Recursion is a programming puzzle game. You solve a level by wiring blocks into a graph: sense the world, branch on what you find, count, remember, act. Then you press play and watch your logic run one tick at a time.

Build the program, not the path

Drag blocks onto the canvas and wire them together. Move Forward, Turn Left, Repeat N Times, If / Else, Wall Ahead?, Store, Recall. Every block spends from a per-tick budget, so a clever program beats a long one — and the score agrees.

Read the world

Wall ahead? Food ahead? Door ahead? Sensors are the only way your program learns anything. Two blocks and one sensor will walk any perimeter forever — the trick is knowing which two.

Your body is your hardware

• Sensor Segments let you see.

• Memory Segments give you variables.

• Processor Segments raise your budget.

They are body segments. Capability costs length, and length is what kills you.

Watch it think

The graph lights up as it runs — which block fired, what the sensors returned, what it cost, what the snake did. When it dies, the game says which death it was: you hit a wall, or you hit yourself. Those need completely different fixes.

70 puzzles now — 100 coming soon

Start with six tutorials that teach you how everything works, then take on 70 handcrafted puzzles. Explore corridors, spirals, combs, keyed vaults, gated floors, and even sensorless runs where you must plan the entire route before moving. Another 30 puzzles will be added in a free update.

Score, then beat your score

Every level carries a budget set by its difficulty. Slow runs spend it. Extra action blocks spend it. Loops, conditions and sensors are free — they are how you save it. Apples always pay for the detour that fetched them. Replay any level to raise your total.

And

• Free Play — an endless board and a combo score

• Custom levels — drop .level files into a folder and they appear in the menu

• Moddable — blocks are Lua, and they hot-reload while the game is running