Evolver — Self-Evolving Agent Memory for OpenCode

Give OpenCode a persistent, auditable evolution memory powered by EvoMap and the Genome Evolution Protocol (GEP).

The plugin recalls what worked in recent sessions during OpenCode compaction, detects improvement signals while OpenCode edits files, and records outcomes when a session is deleted. It uses the same memory format as the Evolver Claude Code and Cursor plugins, so successful patterns can be reused across agent hosts without sharing unrelated project state.

What it does

| OpenCode event | Evolver hook | Effect | |---|---|---| | session.created | hooks/session-start.js | Prepares recent successful outcomes for this workspace. | | experimental.session.compacting | hooks/session-start.js | Adds Evolver memory to OpenCode's compaction context. | | tool.execute.after (write/edit) | hooks/signal-detect.js | Detects evolution signals in edited content. | | session.deleted | hooks/session-end.js | Records one current-diff outcome to local memory. |

Memory is workspace-scoped via <repo>/.evolver/workspace-id, so one project's outcomes do not leak into another project.

Install

npm package mode

Add the package to your OpenCode config:

{
  "$schema": "https://opencode.ai/config.json",
  "plugin": ["evomap-opencode-plugin"]
}

Restart OpenCode. OpenCode installs npm plugins automatically with Bun at startup and loads the server plugin from this package's ./server entrypoint.

Local file mode

For local development or manual installation:

npx evomap-opencode-plugin --install --config-root /path/to/project --force
npx evomap-opencode-plugin --verify --config-root /path/to/project

This writes a small managed delegate file to /path/to/project/.opencode/plugins/evolver.js.

Requirements

• Node.js 18 or newer.
• Git, because outcomes are derived from git diffs.
• OpenCode 1.x.

The plugin works offline by default and writes local memory to ~/.evolver/memory/evolution/memory_graph.jsonl unless the project already has memory/evolution/memory_graph.jsonl or MEMORY_GRAPH_PATH is set.

Optional Evolver engine

The plugin hooks are self-contained and do not require the Evolver engine. To unlock the full CLI, proxy mailbox, asset search, review, and solidify flows:

npm install -g @evomap/evolver
evolver

Running evolver starts the local EvoMap Proxy mailbox. This repository also ships the same thin mcp/evolver-proxy.mjs bridge used by the sibling plugins for MCP clients that can consume it.

Verify

For this repository:

npm test
npm run pack:dry

For a local-file install:

npx evomap-opencode-plugin --verify --config-root /path/to/project

OpenCode's TUI plugin list is for TUI plugins. Evolver is a server/event plugin, so it runs in the background and may not appear in UI-only plugin screens.

Environment variables

| Variable | Purpose | |---|---| | EVOLVER_OPENCODE_HOOKS_DIR | Override the package hooks directory. | | OPENCODE_PROJECT_DIR | Set by this plugin before invoking hooks. | | MEMORY_GRAPH_PATH | Override the local memory graph JSONL path. | | EVOLVER_WORKSPACE_ID | Override workspace scoping id. | | EVOMAP_HUB_URL / EVOMAP_API_KEY / EVOMAP_NODE_ID | Optional Hub recording from the session-end hook. |

License

MIT (c) EvoMap. The bundled hook scripts and OpenCode bridge are clean-room implementations. Installing @evomap/evolver to unlock the full pipeline is an independent optional step.