Open source · MIT · Self-hosted

Forum software that
gets out of your way

Self-hosted, built on Elixir/Phoenix. One server, one command, under ten minutes to a live community.

Read the docs View on GitHub Try the demo →

Install on Ubuntu 22.04 or 24.04

curl -fsSL https://nexusprism.org/install.sh | bash

Installs Docker & Caddy, configures HTTPS via Let's Encrypt, and launches Nexus — automatically.

< 10 minto a live forum

1 servereverything included

MITopen source license

0 feesno hosted dependencies

Features

Everything a community needs

No hosted dependencies, no SaaS fees, no vendor lock-in. Every feature runs on your server.

Spaces & threads

Sub-forums with rich Markdown, code blocks, embeds, mentions, emoji picker, and full-text search powered by PostgreSQL tsvector.

Real-time, out of the box

Phoenix Channels deliver live notifications, direct messages, and feed updates over WebSocket — no Redis, no Pusher, no extra infrastructure.

PWA-ready

Installable on iOS and Android. Push notifications via VAPID. Mobile-native bottom tab bar, overlays, and gesture navigation.

Full moderation suite

Ban, mute, suspend. Report queue with resolution tracking. Pending approval mode. Complete moderation log with audit trail.

Badges & leaderboard

Award custom badges with automatic criteria. Weekly, monthly, and all-time rankings with a fully configurable points system.

Configurable everything

Accent colors, themes, fonts, layout, registration, email provider, object storage, digest emails, PWA icons — all from the admin panel.

Extensions

Extend it without deploying anything

Nexus extensions compile directly into the running VM. No separate service to host, no webhook URLs to configure, no Docker networking to debug. Install from a GitHub URL — Nexus downloads the release, compiles it, runs your migrations, and starts your processes. One server, the whole stack.

Declare every surface your extension contributes in a single manifest.json. Hooks, slots, routes, admin panels, digest sections, toolbar buttons — all validated at install time.

Hook events UI slots Admin panels Digest sections Toolbar buttons Right widgets Profile tabs Composer attach

Browse the extension registry →

manifest.json

// install from Admin → Extensions → Install from URL

  "name":    "Gamepedia",
  "slug":    "gamepedia",
  "version": "1.3.2",
  "module":  "Gamepedia",

  "hooks": [
     "event": "post_deleted" 
  ],

  "routes": [
     "path": "/browse" ,
     "path": "/games/:slug" 
  ],

  "explore": 
    "label": "Games",
    "icon":  "fa-gamepad"
  ,

  "profile_tabs": [
     "id": "gamelog", "label": "Gamelog" 
  ]

Tech stack

Built on proven foundations

Every component chosen for reliability, performance, and simplicity of operation.

Backend

Elixir / Phoenix 1.7

Fault-tolerant, massively concurrent, built for real-time. Phoenix Channels over WebSocket with zero extra infrastructure.

Database

PostgreSQL

Full-text search via tsvector. Background jobs via Oban. No Redis, no Elasticsearch, no separate search service.

Reverse proxy

Caddy

Automatic HTTPS via Let's Encrypt. Zero-config TLS, HTTP/2, and gzip. Reload without downtime.

Deployment

Docker Compose

Single server, one command. The install script handles Docker, Caddy, secrets, and launch end to end.

Background jobs

Oban

Reliable job processing backed by Postgres. Dedicated :extensions queue reserved for extension workloads.

Storage

Local FS or S3

Local filesystem by default. Switch to Cloudflare R2 or any S3-compatible service from the admin panel — no code changes.

Ready to launch your community?

Self-hosted, MIT licensed, and running in under ten minutes.