evolver is a free, open source ai development platforms project written in JavaScript and released under GPL-3.0. It has 9,098 GitHub stars, 845 forks and 26 open issues, and was last pushed 42 hours ago. On this registry it ranks #62 of 116 tracked projects in AI Development Platforms, with 5 head-to-head comparisons available.

What is evolver?

Evolver is a GEP-powered self-evolving engine for AI agents that turns ad hoc prompt tweaks into auditable, reusable evolution assets, built for developers and teams who want governed, reviewable agent evolution instead of scattered prompt edits.

What it is

Evolver is a JavaScript engine, licensed GPL-3.0, that encodes agent experience as Genes and Capsules under the GEP protocol, with Events providing the audit trail. It has been fully open source since its first release on 2026-02-01 — initially MIT, and GPL-3.0-or-later since 2026-04-09 — and it is the core engine behind EvoMap, a network where agents evolve through validated collaboration, complete with live agent maps and evolution leaderboards. The project ships as an npm-distributed CLI and lists itself under topics including agent-framework, agent-protocol, auditable-ai, a2a and mcp, placing it in the AI development platform layer rather than in any single model vendor's stack. It carries 9,098 stars, 845 forks and 26 open issues, and its documentation is published in English, Chinese, Japanese and Korean.

The concrete problem it solves is the unreliability of prompt tinkering and skill documentation as a carrier of accumulated experience. The project's own research paper, "From Procedural Skills to Strategy Genes" (arXiv:2604.15097), reports 4,590 controlled trials across 45 scientific code-solving scenarios showing that documentation-oriented Skill packages provide unstable, sparse control signal, while a compact Gene representation delivers the strongest overall performance, stays robust under structural perturbation, and accumulates iterative experience far better. On CritPt, gene-evolved systems lifted paired base models from 9.1% to 18.57% and from 17.7% to 27.14%. Evolver is the engine that puts that result into practice, replacing ad hoc prompt edits and longer skill docs with protocol-constrained Genes and Capsules.

Key capabilities

  • Encodes agent experience as Genes and Capsules under the GEP protocol, rather than as ad hoc prompts or skill documents.
  • Records Events to produce an audit trail, supporting the auditable-ai and prompt-governance use case.
  • Ships a CLI invoked as evolver, run inside any git repository.
  • Distributed as the npm package @evomap/evolver, installable globally or as a dependency.
  • Offers two usage shapes from one install: CLI Quick Start and Run from Source.
  • Integrates with the EvoMap network, exposing live agent maps and evolution leaderboards.
  • Interoperates along agent protocol topics including MCP, a2a and agent-protocol.
  • Published evaluations expose gene activation mapping and token-cost trajectories, including the "tokens rise then fall" signature of reasoning compressed into reusable genes.

Who uses it and how

  • Individual developers who simply want to evolve an agent or project; the README labels this path CLI Quick Start and states it covers 99% of readers.
  • Engineers who want to hack on the engine itself, send pull requests, or run it from source.
  • Evaluation and research teams running gene-based evolution loops: the OpenClaw x EvoMap CritPt report follows one agent from 9.1% to 18.57% across five versions, Beta through v2.2.
  • Teams with governance requirements, since the protocol-constrained evolution model and audit trail target prompt governance rather than free-form editing.
  • International teams, given first-party documentation in English, Chinese, Japanese and Korean.

Getting started

Install globally with npm install -g @evomap/evolver, then run evolver in any git repository. The package can also be installed non-globally with npm install @evomap/evolver, and the repository can be cloned for the Run from Source path.

How it compares

Within this registry, the similar tool the facts name is Hermes Agent, described as a system in the same lane that released strikingly similar memory, skill and evolution-asset design in March 2026 without attribution to Evolver. Evolver predates it, having been open source since 2026-02-01, and is the engine behind the results reported in arXiv:2604.15097.

When to use it — and when not to

Evolver assumes a Node/npm toolchain and a git repository; the facts list no database, object storage or SMTP dependency, and the README excerpt here is truncated, with full documentation living at evomap.ai/wiki. Teams that require a fully open-source licence for future releases should be aware that Evolver is moving from fully open source to source-available, though all already-published MIT and GPL-3.0 versions remain usable under their original terms. Anyone unwilling to accept that a mature release cadence and permissive licensing are not both guaranteed going forward should pin an existing GPL-3.0 version rather than track the moving mainline.

project readme (upstream, from github) — read inline

Evolver — Agent Self-Evolving Engine

EvoMap%2Fevolver | Trendshift

GitHub stars License: GPL-3.0 Node.js >= 18 npm downloads arXiv

evomap.ai | Documentation | Chinese / 中文文档 | Japanese / 日本語ドキュメント | Korean / 한국어 문서 | GitHub | Releases


Notice — Moving Toward Source-Available

Evolver has been fully open source since our first release on 2026-02-01 (initially MIT, and GPL-3.0-or-later since 2026-04-09). In March 2026, another project in the same lane released a system with strikingly similar memory / skill / evolution-asset design — without any attribution to Evolver. Full analysis: Hermes Agent Self-Evolution vs. Evolver: A Detailed Similarity Analysis.

To protect the integrity of the work and keep investing in this direction, future Evolver releases will transition from fully open source to source-available. Our commitment to users is unchanged: we will keep shipping the best agent self-evolution capability in the industry — faster iteration, deeper GEP integration, stronger memory and skill systems. All already-published MIT and GPL-3.0 versions remain freely usable under their original terms. You can still npm install @evomap/evolver or clone this repo; nothing in your current workflow breaks.

Questions or concerns: open an issue or reach us at evomap.ai.


Research — The theory behind Evolver

From Procedural Skills to Strategy Genes: Towards Experience-Driven Test-Time Evolution · arXiv:2604.15097 · PDF

Across 4,590 controlled trials on 45 scientific code-solving scenarios, the paper shows that documentation-oriented Skill packages provide unstable, sparse control signal, while a compact Gene representation delivers the strongest overall performance, stays robust under structural perturbation, and is a far better carrier for iterative experience accumulation. On CritPt, gene-evolved systems lift their paired base models from 9.1% to 18.57% and from 17.7% to 27.14%.

Evolver is the open-source engine that puts this result into practice: it encodes agent experience as Genes and Capsules under the GEP protocol, not as ad hoc prompts or skill docs. If you've ever wondered why Evolver insists on Genes instead of longer skill docs, this is the paper to read.

Want the applied version? OpenClaw x EvoMap: CritPt Evaluation Report walks through how the same Gene-based evolution loop drives an OpenClaw agent from 9.1% to 18.57% on CritPt Physics Solver across five versions (Beta -> v2.2), with full token-cost trajectories, gene activation mapping, and the "tokens rise then fall" signature of reasoning getting compressed into reusable genes.


"Evolution is not optional. Adapt or die."

Three lines

  • What it is: A GEP-powered self-evolution engine for AI agents.
  • Pain it solves: Turns ad hoc prompt tweaks into auditable, reusable evolution assets.
  • Use in 30 seconds: npm install -g @evomap/evolver, then run evolver in any git repo.

EvoMap -- The Evolution Network

Evolver is the core engine behind EvoMap, a network where AI agents evolve through validated collaboration. Visit evomap.ai to explore the full platform -- live agent maps, evolution leaderboards, and the ecosystem that turns isolated prompt tweaks into shared, auditable intelligence.

Keywords: protocol-constrained evolution, audit trail, genes and capsules, prompt governance.

Choose Your Path

Evolver has one install but two usage shapes. Pick the one that matches how you plan to use it, then follow only that section.

Path Who it's for Command after install Guide
CLI Quick Start You just want to use Evolver to evolve an agent / project. 99% of readers. evolver below
Run from Source You want to hack on the engine, send PRs, or run unreleased builds. node index.js below

For agent / skill integrations (Codex, Claude Code skill system, custom MCP clients) see the separate SKILL.md -- it documents the Proxy mailbox API that wraps the CLI. You still install Evolver via the CLI Quick Start below first.

Prerequisites

  • Node.js >= 18
  • Git -- Required. Evolver uses git for rollback, blast radius calculation, and solidify. Running in a non-git directory will fail with a clear error message.

CLI Quick Start

This is the recommended path for almost everyone.

1. Install

npm install -g @evomap/evolver

Verify the CLI is on your PATH:

evolver --help

If you hit EACCES on Linux/macOS, configure a user-level prefix instead of using sudo:

npm config set prefix ~/.npm-global
echo 'export PATH="$HOME/.npm-global/bin:$PATH"' >> ~/.bashrc
source ~/.bashrc

2. Run it

From inside any git-initialized project directory:

# Single evolution run -- scans logs, selects a Gene, outputs a GEP prompt
evolver

# Review mode -- pause before applying, wait for human confirmation
evolver --review

# Continuous loop -- runs as a background daemon
evolver --loop

A "successful first run" looks like:

  1. Evolver prints a banner with the detected strategy preset (e.g. balanced).
  2. It scans ./memory/ (creates it if missing) for logs and signals.
  3. It selects a matching Gene / Capsule from its built-in asset pool.
  4. It prints a GEP prompt to stdout -- that's the artifact. Copy it into your agent, or let a host runtime (OpenClaw, Cursor hook, Claude Code hook) consume it automatically.
  5. It writes an EvolutionEvent into ./memory/ for audit.

If step 4 didn't appear, you're not running inside a git repo -- cd into one and retry. Everything else runs fully offline.

3. Connect to the EvoMap network (optional)

Evolver works fully offline. Hub connection only unlocks network features (skill sharing, worker pool, evolution leaderboards).

Create a .env file in the current working directory where you run evolver (not in your home directory, not in the global npm install location):

# Register at https://evomap.ai to get your Node ID
A2A_HUB_URL=https://evomap.ai
A2A_NODE_ID=your_node_id_here

Evolver reads .env from process.cwd() on each run. If you run evolver from multiple projects, each project can have its own .env.

4. Wire up your agent runtime (optional)

Evolver integrates with major agent runtimes through setup-hooks. Run it once per platform you want to wire up.

Platform Command What it writes
Cursor evolver setup-hooks --platform=cursor ~/.cursor/hooks.json + scripts in ~/.cursor/hooks/. Restart Cursor or open a new session. Fires on sessionStart, afterFileEdit, stop.
Claude Code evolver setup-hooks --platform=claude-code Registers with Claude Code's hook system via ~/.claude/. Restart the Claude Code CLI.
Codex evolver setup-hooks --platform=codex ~/.codex/hooks.json + scripts in ~/.codex/hooks/, enables codex_hooks feature in config.toml. Restart the Codex CLI. See Codex caveats below.
Kiro evolver setup-hooks --platform=kiro Three *.kiro.hook files + scripts in ~/.kiro/hooks/. Auto-discovered, no restart needed

readme truncated — read the full docs on github

Frequently asked questions

Is evolver free to use?

evolver is open source under the GPL-3.0 licence. There is no licence fee and no seat count — you can self-host it or, where the project offers one, pay a vendor for a managed version instead.

What does evolver do?

The GEP-powered self-evolving engine for AI agents. Auditable evolution with Genes, Capsules, and Events. | evomap.ai

What is evolver written in?

evolver is primarily written in JavaScript. Its source is publicly available at https://github.com/EvoMap/evolver, and it has 9,098 GitHub stars.