immudb-wasm-mcp

An MCP (stdio) server exposing a tamper-evident key-value + SQL store backed by embedded immudb compiled to WebAssembly (immudb-wasm). Pure JS + one .wasm — no native binary, no server, no container.

Because it's published to npm, it runs with zero local build:

npx -y immudb-wasm-mcp

That is exactly what the Claude Code plugin's manifest does, which is why the plugin installs from a marketplace with no build step (see ../plugin).

Tools

immudb_set, immudb_get, immudb_verified_get, immudb_scan, immudb_sql_exec, immudb_sql_query, immudb_status.

immudb_verified_get performs a real in-process cryptographic proof (inclusion + consistency against the current committed root) and returns verified plus the root hash.

Configuration

| Env var | Meaning | Default | |---|---|---| | IMMUDB_WASM_DATA_DIR | Root directory for stores | ~/.immudb-wasm-plugin | | PROJECT_DIR | Project that scopes the store | current working dir |

Each project gets its own store under IMMUDB_WASM_DATA_DIR, named <basename>-<digest of the project path>. The digest keeps two unrelated checkouts that happen to share a folder name from landing on the same single-writer store. Releases before 0.2.0 used the bare basename; a store already sitting at that older path keeps being used, so upgrading never strands an existing ledger.

Unset values passed as an unexpanded ${VAR} placeholder are ignored.

Use as an MCP server (outside the plugin)

One command, no repository clone and no build:

claude mcp add immudb-wasm -- npx -y [email protected]

Or declare it in an MCP config file directly:

{
  "mcpServers": {
    "immudb-wasm": {
      "command": "npx",
      "args": ["-y", "[email protected]"],
      "env": { "IMMUDB_WASM_DATA_DIR": "/path/to/data" }
    }
  }
}

The plugin in ../plugin does nothing more than this — its manifest holds no code, just the same npx invocation — so registering the server directly is equivalent and skips the git-based plugin transport.

Notes

• Single writer. The embedded store is single-process; a second open of the same directory by a live process is rejected. A lock left by a crashed process is detected and reclaimed.
• Depends on the immudb-wasm package, which bundles the .wasm.

BUSL-1.1 (packages the immudb engine).