Developing on PCs with Limited Resources

Development
1

My recommendation for a calm, sustainable dev machine: 64 GB RAM, a swapfile the same size as RAM, a fast external SSD with at least 500 GB, and only the services you actually need right now.

Not every machine is a high-end workstation, and that is fine. If you work intentionally, keep Docker data off the system disk, and clean up regularly, you can stay productive even on modest hardware.

Goal Hardware

If you want long-term stability and less friction, this is a solid target:

  • 64 GB RAM
  • a swapfile the same size as RAM
  • an external SSD with more than 500 GB
  • enough room for Docker images, volumes, build cache, and local repositories

The SSD is often the cheapest and most effective upgrade. If disk space is tight, move Docker data, caches, and ideally your working directory to that drive.

On Linux, you can move Docker to a different data path:

{
  "data-root": "/mnt/ssd/docker"
}

Then restart Docker:

sudo systemctl restart docker

Make sure the mount is available before Docker starts. Otherwise the daemon may fall back to the system drive or fail to start cleanly.

On macOS and Windows, this is usually handled through Docker Desktop settings rather than daemon.json.

For swap: on Linux, a swapfile equal to your RAM size is a good buffer against memory spikes, OOM kills, and hard crashes. If you have less RAM, the same idea still helps, but you will need to be even stricter about keeping the stack small. On Windows and macOS, the OS manages virtual memory itself, but free disk space still matters a lot.

Load Only What You Need

For a broad stack like the Community Hub, it helps a lot not to start everything at once. If you are only working on Discourse, you do not automatically need Mastodon, Pixelfed, PeerTube, or Friendica in the same session.

The main lever is each role’s config/main.yml. That is where Compose services are enabled or disabled. The rule is simple:

  • use enabled: true only for services you actually need
  • set enabled: false for optional services
  • for shared services, also set shared: false if they are not needed

Example of a slim local Discourse configuration:

compose:
  services:
    discourse:
      enabled: true
    database:
      enabled: true
      shared: true
      type: "postgres"
    redis:
      enabled: true
    oidc:
      enabled: false
      shared: false
    logout:
      enabled: false
    ldap:
      enabled: false
      shared: false
    dashboard:
      enabled: false
    matomo:
      enabled: false
      shared: false
    css:
      enabled: false

This is a development profile, not a production target. If you need to test SSO, LDAP, or analytics, enable those services deliberately. But on weaker hardware, the general rule is: as little as possible, as much as necessary.

At bundle level, the same principle applies. If you are only changing Discourse in the Community Hub, do not start the whole stack unless you need it.

Test Smarter

On small machines, it helps to limit validation to the one role you are actually touching.

For Discourse, this is usually the best start:

APP=web-app-discourse make test-local-dedicated

If the local inventory and stack are already in place, this is often the faster iteration loop:

APP=web-app-discourse make test-local-rapid

I would only use make test-local-full on weaker hardware if you truly need broad coverage and you have enough time and resources.

Measure Before You Delete

Before cleaning up, it is worth checking what is actually consuming space:

docker system df
docker ps -a
docker images
journalctl --disk-usage
df -h

That usually makes it much easier to see whether the real issue is Docker, journald, a package cache, or simply the project state.

Docker Cleanup

First: there is no single docker prune command. In practice, people usually mean one of these.

For a single project, this is the first cleanup step:

docker compose down --volumes --remove-orphans

If you need the big cleanup, these are the usual commands:

docker system prune -a --volumes -f
docker container prune -f
docker image prune -a -f
docker volume prune -f
docker network prune -f
docker builder prune -a -f
docker context prune -f

When I use what:

  • docker compose down --volumes --remove-orphans for one project
  • docker system prune -a --volumes -f for the big hammer
  • docker builder prune -a -f when build cache grows too large
  • docker volume prune -f when old volumes consume space
  • docker image prune -a -f when old images pile up
  • docker network prune -f when old networks remain
  • docker context prune -f when you have many stale Docker contexts

If you use Buildx, add this when needed:

docker buildx prune -a -f

Repo and Project Cleanup

Inside this repository, these commands help a lot:

make down
make stop
make clean
make clean-sudo
make cleanup-ci-images
make test-local-cleanup
make test-local-reset

Quick explanation:

  • make down stops the stack and removes volumes
  • make stop stops the stack but keeps the state
  • make clean removes ignored Git files
  • make clean-sudo does the same with sudo, if root-owned files exist
  • make cleanup-ci-images removes old CI images
  • make test-local-cleanup cleans local test state
  • make test-local-reset resets the local inventory

If you often switch branches or work on only one role at a time, a disciplined down and clean routine usually saves more space than trying to recover later with a huge prune.

Linux

Common

Use these on most Linux setups before you go distro-specific:

docker compose down --volumes --remove-orphans
docker system prune -a --volumes -f
docker builder prune -a -f
docker image prune -a -f
docker volume prune -f
docker network prune -f
docker context prune -f
journalctl --vacuum-size=100M
journalctl --vacuum-time=3h
pip cache purge
npm cache clean --force
yarn cache clean
go clean -cache -modcache
cargo clean

Optional, if you use Flatpak:

flatpak uninstall --unused -y

Arch

sudo pacman -Scc --noconfirm

Debian / Ubuntu

sudo apt-get clean
sudo apt-get autoremove --purge -y

Fedora / CentOS

sudo dnf clean all
sudo yum clean all

This matches the general idea used by the repo’s cleanup roles: keep package caches, tool caches, temp files, and journald under control.

macOS

On macOS, focus on Docker Desktop and Homebrew:

brew cleanup --prune=all
brew autoremove
docker system prune -a --volumes -f
docker builder prune -a -f

If you follow the repo setup, macOS works best when the stack runs in a Linux environment such as Lima. In that case, the same general rule applies: keep Docker and build caches small, and place the Docker disk location on a larger drive if possible.

Windows

On Windows, the most reliable setup is WSL2. In practice, that means:

  • do Docker cleanup inside WSL2 or directly via the Docker CLI
  • use Windows-side cleanup tools for host cleanup
  • run wsl --shutdown when you want memory returned to the host

Useful Windows commands:

docker system prune -a --volumes -f
docker builder prune -a -f
wsl --shutdown
cleanmgr /sageset:1
cleanmgr /sagerun:1
DISM /Online /Cleanup-Image /StartComponentCleanup

cleanmgr /sageset:1 is typically configured once as Administrator. After that, cleanmgr /sagerun:1 reuses the same cleanup profile.

If you are working in WSL2, you can also use the Linux commands from the Linux section inside the WSL shell. That is often the cleanest approach, because the Docker workload usually lives there.

Standard Routine

When the machine starts feeling tight, I usually do this:

  1. Start only the role I actually need.
  2. Stop the stack cleanly with make down or docker compose down --volumes --remove-orphans.
  3. Clear Docker cache with docker builder prune -a -f and docker system prune -a --volumes -f.
  4. Clean host caches depending on the operating system.
  5. Start fresh again.

It sounds simple, but that is exactly what keeps smaller machines usable over time.

If you have to develop on limited hardware, the best strategy is not “more power”, but “less load per session”.

If you want, I can also turn this into a shorter Discourse-ready version with a more conversational forum tone.