XERJ

Judgement

What it is

Building block

What it does

A single Rust binary that indexes code, docs, logs, CSV and PDFs for full-text, vector and hybrid search, with an Elasticsearch-compatible API and an MCP server for agents.

Adopt it when

You want a small self-contained search engine for local documents or agent memory without running an Elasticsearch cluster.

Watch out

Still on release candidates (v1.0.0-rc.101) and about four months old, so the API and index format may keep changing.

Ready for

Experimental

Runs as

Command line and self-hosted server

Built with

Rust

How established

New: started 4 months ago, latest release v1.0.0-rc.101.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-06 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: XERJ → Rust → runs on a microchip

How compilers were built, back to punched paper tape

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