The brain
Project status — future development is uncertain
Plexo was built to be the intelligence layer behind our own apps. Since then we've moved to Hermes Agent, which covers most of what we'd planned to build here — so whether development continues is undecided.
- The code stays available — MIT-licensed, self-hostable, nothing is being pulled.
- The hosted SaaS is offline; self-hosting is the supported path.
- Issues and PRs may go unanswered for now.
AI that remembers, reasons, and acts.
Plexo is an AI agent platform. Not a wrapper around an API. Not a chatbot with plugins. A persistent intelligence layer with semantic memory, domain reasoning, and agents that actually do the work. Every Joeybuilt product shares the same brain.
Not another AI wrapper.
Most AI products are a thin layer over someone else's API. Plexo is the operating system. Memory that persists. Context that compounds. Agents that work unsupervised. Intelligence that every app in the ecosystem inherits for free.
Semantic memory
Every interaction gets compressed into structured knowledge. Facts, patterns, and principles — tiered by recency and relevance. Your agent doesn't start from zero every time. It builds on everything it's learned.
Semantic Context Lattice
Your domain knowledge mapped as concept attractors, regions, and transformation rules. Plexo doesn't just recall — it navigates your knowledge space to find connections you didn't ask for. Drift-protected. Self-evolving.
Persistent agents
Agents that run for hours, use tools, subscribe to channels, and pick up where they left off. They file PRs, send emails, manage schedules, and report back. Not chatbots. Workers.
Intelligent routing
Per-task model selection with fallback chains. Planning gets a reasoning model. Quick replies get a fast one. Cost ceilings, quality gates, and automatic provider failover — all invisible to the user.
One brain, every app.
Every Joeybuilt product is an App Profile on Plexo. Each gets its own schema, its own agent scope, its own keyspace. But they share intelligence, share memory, and share the ability to act on each other's behalf. Your finance app knows about your calendar. Your knowledge base informs your email. Everything flows through the same brain.
Extensions
Agents, Skills, Channels, Tools, Connectors — individually installable units that extend what Plexo can do. Build your own or install from the Hub. The ecosystem grows with every contributor.
plexoDID
Federated identity across Plexo nodes. Every node has a decentralized identifier. Agents, users, and services authenticate across the mesh without a central authority.
Model Foundry
Train your own models on your own data. Plexo collects domain-specific training examples from every interaction, then lets you fine-tune models that understand your world. Provider-agnostic. Your data, your models.
Telemetry
Honest, opt-in, documented publicly. Self-hosted users send nothing by default. The telemetry spec is in ANALYTICS.md in the repo.
Run it yourself
Plexo ships as Docker Compose. Clone the repo, set your env vars, docker compose up. Self-hosting is the only supported path now — there is no managed tier to upsell you into.
git clone https://github.com/joeybuilt-official/plexo.git
cd plexo
cp .env.example .env # configure your secrets
docker compose up -d