NodeBB vs Discourse

NodeBB and Discourse are the two forums in our catalog with an official Docker route. Both give you categories, mentions, notifications, moderation and search in a modern browser UI; both are GPL. The difference is how much each one brings and how much it asks of the server. Discourse is a large Rails application that arrives as one launcher-built container with chat, polls and an AI plugin already in the repository, on a documented 1 GB floor with swap. NodeBB is a Node.js forum with a "common core" and npm plugins, installs from a stock Compose file with a web installer, idled well under Discourse's floor in our check, and federates over ActivityPub out of the box.

How each one installs

NodeBB is the forum whose Docker route is a Compose file. Upstream's repository carries a docker-compose.yml with a nodebb service beside a mongo service and postgres and redis profiles; our snippet uses the MongoDB pairing and pins the official GHCR image. First start installs dependencies and runs a build, which takes a few minutes, then a web installer answers on port 4567 where you enter the database details and create the admin account. The docs say that "For MongoDB, please notice that you need to use admin as database at the moment", because the official Mongo image does not apply the initial database the way setup expects. Two honesty notes from the same page: "The configuration (and this documentation) is community-maintained", with support routed to the community forum, and upstream advises against relying on the default Compose setup for a real deployment. State is spread over four volumes: config, uploads, the build directory and the database.

Discourse supports exactly one install. Its install guide says "The only officially supported installs of Discourse are Docker based", and that Docker install is not a Compose file. You clone discourse_docker into /var/discourse, and the launcher script builds a single container from the standalone template, which "bundles all of the software required to run Discourse into a single container": PostgreSQL, Redis, the Rails web app and its workers. Upstream's cloud guide promises you can "Set up Discourse in about 10 minutes", most of it the build. Every later change, plugin install or config edit is an edit to containers/app.yml followed by ./launcher rebuild app, which the launcher README defines as "Rebuild a container (destroy old, bootstrap, start new)", so the forum is offline while it runs. It also needs a hostname and ports 80 and 443 free for the bundled Let's Encrypt setup; Discourse vs Flarum covers the hostname and SMTP terms in detail.

The database follows the same split. NodeBB "supports either Redis, MongoDB, or a PostgreSQL database", with Mongo the default; the PostgreSQL page says "NodeBB supports PostgreSQL as its primary data store", so a team already running Postgres can skip MongoDB. Redis is the odd one out: because the whole database lives in memory, your "system memory needs to be twice as large (if not more) than your dataset". Discourse decides for you: PostgreSQL and Redis run inside the one container, sized by the installer.

We rate both 2 out of 5 to deploy: a Compose file and a web installer, or a wizard and a long build.

Features in the box, and how you add more

Discourse ships a lot in its core repository. The plugins directory there holds dozens of first-party plugins: chat, poll, discourse-ai, discourse-solved, discourse-reactions, discourse-assign, discourse-data-explorer, discourse-openid-connect and more. Chat is the one people ask about most, and its guide says "This plugin is bundled with Discourse core"; you switch it on under /admin/plugins. Third-party plugins are git repositories you add to app.yml, followed by a rebuild.

NodeBB keeps the core smaller and leans on its ecosystem. The README says "NodeBB by itself contains a "common core" of basic functionality" and that "additional functionality and integrations are enabled through the use of third-party plugins". Those plugins "are hosted on npm, and are created by third-party developers", and the docs steer you to the ones listed in the admin control panel, which are matched to your NodeBB version; installing others from the command line is possible but discouraged because an incompatible plugin can crash the forum. Real-time is in the core, not a plugin: NodeBB "utilizes web sockets for instant interactions and real-time notifications". There is no built-in chat room in the Discourse sense.

Federation

This is the one feature where NodeBB is ahead rather than lighter. The ActivityPub docs say "ActivityPub integration is controlled via a global toggle switch in the admin panel", and on a fresh install "all categories will federate by default", so a Mastodon account can follow and reply into a federated category. Discourse has an ActivityPub plugin in its GitHub organisation that "allows you to publish Discourse posts via ActivityPub", but it is a separate plugin, installed through app.yml and a rebuild, and its topic on Meta is tagged "experimental".

Licences are close cousins: NodeBB "is licensed under the GNU General Public License v3 (GPL-3)", Discourse is "Licensed under the GNU General Public License Version 2.0 (or later)"; the difference only bites on redistribution.

Footprint and setup

NodeBB's install docs list "512MB RAM" under hardware requirements, with the Ubuntu guide adding that "Installing NodeBB's dependencies may require more than 512 megabytes of system memory", so give the first build headroom or swap. In our install check (GCP e2-standard-2, Ubuntu 26.04, October 2026), NodeBB plus MongoDB idled at ~217 MB of RAM and ~3.0 GB of disk, which includes the first-start dependency install and build. Discourse we did not measure; it documents "1 GB RAM minimum (with swap)", a "modern single core CPU, dual core recommended" and "10 GB disk space minimum", and its installer "will offer to create swap space" on small servers. On a 1 GB VPS, NodeBB is the forum that leaves room; Discourse is the forum that fills it and wants the swap.

Which to choose

Choose NodeBB if you want the lighter forum: a Compose file and a web installer, your choice of MongoDB, PostgreSQL or Redis, real-time posting in the core, npm plugins and themes you manage from the admin panel, and ActivityPub federation switched on without a plugin, all at ~217 MB idle on a 512 MB floor.

Choose Discourse if you want chat, polls, solved answers, reactions, the AI plugin and dozens of other first-party plugins in the repository on day one, and you accept its terms: one launcher-built container, a rebuild for every plugin or config change, a hostname, and 1 GB of RAM with swap as the documented minimum.

Neither wins outright: the bigger product with one sanctioned way to run it, or the smaller, federating one that fits the server you already have.

Running NodeBB or Discourse on a VPS

Both installs are verified on Ubuntu 26.04. The pinned Compose file with the MongoDB credentials in .env is on the NodeBB page, and the launcher steps, including the DISCOURSE_SKIP_EMAIL_SETUP route and a command-line admin, are on the Discourse page. NodeBB listens on plain HTTP 4567, so put a TLS reverse proxy in front and set the site URL in the installer to the public address; Discourse terminates TLS itself on 80 and 443. Run NodeBB's installer yourself as soon as the container is up, since the first visitor to port 4567 gets to create the admin.