conexus 5.9.1

Self-hosted semantic search and knowledge management for LLM-driven development

Nexus

Persistent memory and semantic search for Claude. Three storage tiers that survive across sessions, an event-sourced document catalog with typed links, and a specification-before-code workflow for tracking decisions. Local-first; no API keys required. Knowledge compounds across conversations instead of evaporating when the window closes.

Start here: How I actually use Nexus — the conceptual overview and the shape of the substrate. Then Installing Nexus — a ten-minute hands-on walkthrough from uv tool install through your first search.

Install for Claude

Three surfaces share one host substrate. Pick the one that matches how you use Claude.

Claude Desktop chat

Download conexus.mcpb from the latest release and double-click. Claude Desktop registers it under Settings → Connectors. Requires uv on the host PATH; deps resolve on first launch (~20s).

Claude Code (terminal)

/plugin marketplace add Hellblazer/nexus
/plugin install conexus@nexus-plugins

The plugin ships 13 specialized agents, 43 skills (RDR lifecycle, plan-centric retrieval, dev workflows), and 36 MCP tools split across two focused servers. Session hooks load project context at startup.

Claude Cowork

Works automatically once the conexus plugin is installed in Claude Code on the host. State round-trips bidirectionally with the host CLI through the T2 daemon.

For the full deployment story across all three surfaces (install, daemon lifecycle, drift detection, uninstall), see docs/desktop-deployment.md.

What it does

• Persistent memory — three storage tiers (T1 session scratch, T2 SQLite memory bank, T3 semantic knowledge store) so Claude remembers across conversations.
• Semantic search — index your code, docs, RDRs, and PDFs once; search by meaning afterward. Tree-sitter AST chunking across 23 languages, CCE prose chunking, PDF auto-routing.
• Typed document catalog — Xanadu-inspired addressing with typed links (cites, implements, supersedes). Walk from a design doc to the code that implements it.
• RDR: Research-Design-Review — write a spec before you code. Captures the problem, research, alternatives, and chosen approach. The corpus is searchable, so prior decisions surface during new design work.
• Local-first — default install runs entirely on your machine with ONNX MiniLM + local ChromaDB. Voyage AI + ChromaDB Cloud are opt-in for higher-quality embeddings.

CLI quick-start

uv tool install conexus                  # install the nx CLI (built-in ONNX MiniLM embedder)
nx init                                  # guided: choose your local embedder (384 vs bge-768)
nx daemon t2 install --autostart         # register the T2 daemon (one-time)
nx doctor                                # verify installation
nx index repo .                          # index your repo + discover topics
nx search "how does retry work"          # semantic search, fully local

nx init presents the embedder choice (recommended bge-768, ~140 MB one-time download, for materially better local search, vs the bundled 384-dim MiniLM), adds the [local] extra for you when you pick bge-768, and migrates any pre-existing 384-dim collections safely. To request the higher-quality embedder directly at install time instead: uv tool install "conexus[local]".

The nx CLI provides direct access to all storage tiers, indexing, search, the catalog, and taxonomy. See Getting Started for a walkthrough, CLI Reference for every command and flag.

Updating

uv tool upgrade conexus                  # upgrade the nx CLI — PRESERVES your extras (e.g. [local])

Always upgrade with uv tool upgrade conexus. It retains the spec you installed with, so a [local] install stays a [local] install. Do not upgrade with uv tool install conexus --force / uv tool install conexus — that resets the install and drops [local], silently downgrading your embedder from 768-dim to 384-dim. With existing 768-dim collections that produces a dimension mismatch and search returns nothing. If you hit that, reinstall the extra: uv tool install --reinstall "conexus[local]".

When you update the Claude Code plugin (/plugin update), upgrade the CLI to the matching version at the same time so the two stay in lockstep.

Going deeper

If you want to...	Read
Understand the architecture	Storage Tiers, Architecture
Write an RDR	RDR: Research-Design-Review
Index a repo or PDFs	Repo Indexing
Configure or tune	Configuration
Run in containers or Cowork	Container Integration
Browse the docs tree	docs/README.md
Read the conceptual story	How I actually use Nexus
Walk through a fresh install	Installing Nexus
Browse the full series	Tensegrity blog

Prerequisites

Python 3.12+, uv, git. For hybrid search, ripgrep. For the Claude Code plugin, Node.js (the bundled sequential-thinking and context7 servers spawn via npx).

License

AGPL-3.0-or-later. See LICENSE.