REPLbot is a Slack bot that allows you to control a REPL from within Slack. It comes with a few REPLs (Go 🥳, Java,
NodeJS, PHP, Python, Ruby, Scala, Kotlin, C++ and Ubuntu/Bash), but you can easily make/bring your own.

Why ...?

I thought it might be a fun way to collaboratively dabble with a REPL in a team. Yes, I could have gone for a terminal
in a browser, but there's nothing like having it right there in Slack. Mainly I did it because it was fun though. 😄

How it works

I use tmux and the tmux capture-pane command to run most of the show. It's simple, but effective. In the first
iteration I tried using a pseudo terminal (pty) directly, but with all the escape sequences and commands, it was getting
kinda tiresome, and I was spending time with stuff that I didn't want to spend time with (though I learned a lot!).
And tmux does its job so well.

The actual REPLs are just simple scripts (see script.d folder), so they could be anything you like.
I highly recommend using Docker to provide somewhat of an isolation, though you'll probably still need to trust the
people using the bot if you give them an entire REPL.


Install steps:

  1. Make sure tmux and probably also docker are installed. Then install REPLbot using any of the methods below.
  2. Then edit /etc/replbot/config.yml to add Slack bot token. The config also explains how to create a Slack app and acquire this token.
  3. Review the scripts in /etc/replbot/script.d, and make sure that you have Docker installed if you'd like to use them.
  4. If you're running REPLbot as non-root user (such as when you install the deb/rpm), be sure to add the replbot user to the docker group: sudo usermod -G docker -a replbot.
  5. Then just run it with replbot (or systemctl start replbot when using the deb/rpm).

Debian/Ubuntu (from a repository):

curl -sSL | sudo apt-key add -
sudo apt install apt-transport-https
sudo sh -c "echo 'deb [arch=amd64] debian main' > /etc/apt/sources.list.d/"  
sudo apt update
sudo apt install replbot

Debian/Ubuntu (manual install):

sudo apt install tmux
dpkg -i replbot_0.1.2_amd64.deb


# Make sure that "tmux" is installed
rpm -ivh

You can configure the Docker image by mounting a config directory (containing config.yml) to
/etc/replbot. To be able to use most of the pre-packaged script.d REPLs (to be mounted to /etc/replbot/script.d),
you'll need to give the REPLbot image access to the Docker socket file. This allows the container to spin up other containers
on the host. This is a security risk and considered bad practice, but it's the only way.

docker run --rm -it \
  -v /etc/replbot:/etc/replbot \
  -v /var/run/docker.sock:/var/run/docker.sock \


# Be sure "tmux" is installed
go get -u

Manual install (any x86_64-based Linux):

# Make sure that "tmux" is installed
sudo tar -C /usr/bin -zxf replbot_0.1.2_linux_x86_64.tar.gz replbot