Precession

A simple tmux session manager

Define arbitrarily complex tmux sessions in a declarative way, using yaml, and spin them up with a simple command.

Format

Precession follows a dead-simple format for defining sessions. It follows the tmux naming scheme of "sessions", "windows" and "panes". Here's a quick example

# Sessions are defined at the top level
name: My web project
root: ~/projects/my_web_project

# Windows are defined under the `windows` key
windows: 
  - name: Code
    cmd: vim .                             # Simple windows can define an optional `cmd` to run
    
  - name: Dev servers
    layout: even-horizontal
    panes:                                 # More complex windows can define a set of panes
      - docker-compose up
      - cd server && cargo run
      - cd client && yarn start
      
  - name: Tests
    layout: even-horizontal
    panes:
      - cd server && cargo watch -x test
      - cd client && yarn test --watch
      -                                    # "An empty" pane just drops you into a shell

FAQ

Why not just write a bash script?

...because I really don't want to. Setting up these sessions happens rarely enough that I'd have to read through the man pages every time to brush up on tmux's syntax. I know yaml, and it takes a whole of 10 seconds to grok Precession's format. But hey, you do you.

Why another tmux session manager?

It's not like people haven't thought of this before. The popular option, by far, is tmuxinator. I've used it before, with little issue, and it's great. It just rubs me the wrong way that to use it, I need to install a whole bunch of Ruby dependencies. A simple utility forcing me to install a bunch of extra cruft into my system's global namespace is not something I can get behind.

TODO

• [✓] Support panes
• [✓] Support layouts
• [✓] Have Serde infer defaults, rather than having conditionals littered throughout.
• Do some amount of validation? A window can't have both a cmd and a panes field.
• Check if a session already exists, and attach if so
• Figure out why tmux server is crashing on exit