devshell is a Docker image containing my preferred development environment (which happens to be text-based).

On start, a dev tmux session is created. When the tmux session ends, so does the docker container.

lib/devshell.zsh contains a zsh function dev. This handles starting the container and attaching to the tmux session inside of it. All terminal features seem to work well inside of docker run -it, including 256 color support and bracketed paste mode.

devshell supports multiple instances per user/host (separate containers, so separate tmux sessions). The default instance name is 1. To list running containers, run dev -l. To attach to a specific instance, run dev $instance. To kill an instance, run dev -k.

The environment variable DEVSHELL is set to the current instance name.

Starting with a barebones Fedora docker image, bin/build.sh installs everything I use for day to day dev work.

Versions are pinned in lib/versions. Some code needs to be written to look for updates here (dependabot style).

We pass through $HOME (and optionally other directories, set $DEVSHELL_EXTRA_MOUNTS), so this makes the dev environment ephemeral. Repave early, repave often.

/var/run/docker.sock is also passed through - this enables you to still interact with the local dockerd as part of dev activities.

Since we pass through filesystems, it's important to have matching UIDs/GIDs. This has to happen at run-time (one docker image build may get run on multiple hosts), so as part of starting the image we pass through our own UID and docker's GID and set them appropriately in the container.

Since we aren't fully managing our $HOME, dotfiles are out of scope. To help manage dotfiles, see my dotfiles repo.

• ssh-agent pass through (considering moving $SSH_AUTH_SOCK to be somewhere in $HOME)