Left panel is the ecology where evolution happens. Right panel is a maze. I pick an evolved organism and drop one cell into the maze. Some genomes fail. Some explore the whole thing. Zero control after injection.
The cells don't have functions like 'move left' or 'eat food'. Each cell runs a small evolved gene network that reads local inputs and writes to registers. Physical consequences follow from the register values. The cell doesn't know it's navigating. Its internal chemistry just happens to produce movement.
~2000 lines of C. Single thread. Runs on a laptop