parallel-code: Open-Source Tool Runs Claude Code, Codex, and Gemini CLI Side-by-Side in Isolated Git Worktrees

GitHub·medium signal

The parallel-code GitHub project by johannesjo lets developers run Claude Code, OpenAI Codex, and Gemini CLI simultaneously, each in its own isolated git worktree. This enables head-to-head comparison of different coding agents on the same task, competitive solution generation, and cherry-picking the best output. Practical for teams evaluating which agent handles their specific codebase best, or for using multiple agents in complementary roles on the same feature.