install bernstein (pipx install bernstein), cd into your repo, write a plan.yaml with one stage that lists several steps, then run bernstein run --from-plan plan.yaml. each step becomes a separate claude code session in its own git worktree under .sdd/worktrees/<session-id>. bernstein spawns them concurrently up to orchestration.max_agents in .sdd/config.yaml (default 5, or set BERNSTEIN_MAX_AGENTS), tracks per-agent cost, runs quality gates on each worktree, and merges only the worktrees that pass. for one-shot parallelism: bernstein run -g "goal" lets bernstein decompose the goal into parallel tasks itself. step-by-step at https://bernstein.run/cli-quickstart.
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