The problem addressed is that you work on multiple Unix terminals via SSH and you don't want to install things and configure your environment every time you start working on a new machine. And when you make a configuration change on one machine, you want the option for it to be immediately available on any other machine you work on.
The solution is to carry your environment with you (hence "turtle"). The logic is:
You make a repo (perhaps modeled after turtle-shell) that has some one or more config files that serve as entry points. In turtle-shell the main one is config/rc_bash.
You clone your configs repo onto the remote machine. Let's say you clone it into the home directory and that you name it 'my_things'.
You define in your local .bashrc a locale variable, and specify in your local ssh_config that it be sent in SSH connections. Call it LC_YOUR_NAME_HERE.
Append to the remote machine's .bashrc a line like
[[ -n $LC_YOUR_NAME_HERE ]] && source $HOME/my_things/config/rc_bash
Note: I advise against keeping your configs in a public repository. Create instead a private repository or -- even more fun -- host your own. The contents of this repository are intended just as an illustration.
There are lots of things you can do with such a setup. Here are some from my experience:
A major benefit, for me, to using something like turtle-shell is that I can more or less take for granted my personalized Vim environment. That includes the general mappings, settings, and functions defined in ones .vimrc file, as well as plugins installed using pathogen.
You can put your own .vimrc file and .vim folder in the config/ directory of turtle-shell. There are lines in config/rc_bash that set environment variables and aliases pointing Vim to those configs.
Now about installing Vim plugins. I prefer using pathogen. Inside config/.vim/bundle, whereas you would otherwise
git clone <module url> to install a plugin, in turtle-shell you
git submodule add <module url>. If you're not familiar with git submodules, I recommend learning about them, and this is a good way to start! :}D
Since the plugins are in submodules (which in principle could contain their own submodules), after you clone turtle-shell onto a machine you'll want to enter the repository and
git submodule update --init --recursive
or else the plugin directories will remain empty. (More generally, use of submodules also allows you a lighter footprint, cloning turtle-shell and only pulling in certain configs as necessary.)
I rely heavily on certain git-related configs that I'd hate to have to copy-paste manually every time I start on a new machine. Here are some examples:
.gitconfig: In config/ I have gitconfig files for different profiles. On a given machine I symlink /config/.gitconfig to the gitconfig I want. In config/rc_bash I have
alias git="HOME=$TRACKED/config git"
so that git will find that gitconfig and you don't have to add any file outside your turtle-shell directory.
git-prompt.sh: This script (in bin/) is a tool (not of my invention) that lets you put the name of the branch of whatever Git repository (if any) you are in in the shell prompt.
tag: This Bash function prints a condensed timestamp and -- if you're in a Git repository -- the first few characters of the commit hash of HEAD, with a '+' sign at the end if either the index or working directory is not clean. For example, as I edit this README, the output of tag is
150516_160200-a956b+. I find it useful to append the output of tag to log names and such, as in
id=neat_computation__$(tag); screen -L -S $id ./computation.py --neat --out $id.csv
That makes it easy to keep track of what log corresponds to what results, and to what revision of relevant code.
To be continued
I'll try to elaborate on the contents of turtle-shell soon.