evo alternatives
Curated alternatives to evo — and why you'd switch.
autoresearch
Karpathy's autoresearch loop as an installable skill for Claude Code, OpenCode and Codex: constraint + mechanical metric + autonomous modify→verify→keep/discard iteration.
Why switchSame lineage — Karpathy's autoresearch loop for coding agents. The skill is a single-branch keep/discard hill-climb; evo adds tree search, parallel worktree subagents, shared failure traces, gates and a dashboard. Start with the skill, graduate to evo.
Full comparison →sia
Self-improving loop from the SIA paper: Meta, Target and Feedback agents evolve a task agent's harness AND weights against a benchmark — #1 on MLE-Bench Hard, 14x kernel speedups.
Why switchBoth run autonomous improve-against-a-benchmark loops with paper-adjacent rigor. evo points coding agents at YOUR codebase (tree search over commits); SIA generates a task-specific agent and evolves the agent itself — harness and weights.
Full comparison →fractal
Hierarchical agent loops: nodes iterate toward a goal in their own git worktree and spawn children for subtasks — the tree grows to fit the problem. Hard caps, SQLite run log, live TUI.
Why switchBoth grow trees of worktree-isolated agent loops. evo's tree searches for a better SCORE on a fixed benchmark; fractal's tree decomposes a TASK into subtasks. Optimization vs delegation — same shape, different objective.
Full comparison →