symphony

Symphony is the control plane for parallel AI software development: plan once, execute many approaches, compare results, and merge the winner It turns product intent into parallel implementation runs you can compare and control. Instead of coding one approach at a time, Symphony forks multiple isolated Git worktrees (“worlds”), runs Codex agents on different strategies, executes the same test/playback harness on each, captures traces and diffs, and lets a human pick the best outcome to merge. Problem It Solves Teams still build software in a serial loop: pick one approach, implement, test, backtrack, repeat. That makes experimentation slow, risky, and hard to trust. Planning artifacts are also disconnected from execution, and multi-agent workflows are often opaque.