Today I Learned - Effective Pairing with Mob.sh
As someone who enjoys leveraging technology and teaching, I'm always interested in ways to simplify the teaching process.
For example, when I'm teaching someone a new skill, I follow the "show one, do one, lead one" approach and my tool of choice for the longest time was LiveShare by Microsoft.
Using VS LiveShare
I think this extension is pretty slick as it allows you to have multiple collaborators, the latency is quite low, and it's built into both Visual Studio Code (VS Code) and Visual Studio.
Drawbacks to LiveShare
Editor Lock-In
First, participants have to be using Visual Studio or VS Code. Since there's support for VS Code, this isn't quite a blocker as it could be. However, let's say that I'm wanting to work with a team on a Java application. They're more likely to be using IntelliJ or Eclipse as their editor and I don't want someone to have to change their editor just to collaborate.
Security Concerns
Second, there are some security considerations to be aware of.
Given the nature of LiveShare, collaborators either connect to your machine (peer-to-peer) or they go through a relay in Azure. Companies that are sensitive to where traffic is routed to won't allow the Azure relay option and given the issues with the URL creation (see next section), the peer-to-peer connection isn't much better.
To start a session, LiveShare generates a URL that the owner would share with their collaborators. As of today, there's no way to limit who can access that link. The owner has some moderator tools to block people, but there's not a way to stop anyone from joining who doesn't have the right kind of email address for example.
Introducing Mob.sh
While pairing with a colleague, he introduced me to an alternative tool, mob.sh
At first, I was a bit skeptical of this tooling as I enjoyed the ease of use that I got with LiveShare. However, after a few sessions, I find that this tool solves the problems that I was using LiveShare for just as good, if not better.
How It Works
At a high level, mob.sh is a command line tool that is a wrapper around basic git commands.
Because of this design choice, it doesn't matter what editor that a participant has, as long as the code under question is under git source control, the tooling works.
Let's explore how a pair, Adam and Brittany, would use this tool for work.
Adam and Brittany Start Pairing
Adam is looking to solve a logic issue in an AWS lambda could use Brittany's guidance since he's new to that domain.
Adam creates a new feature branch, fixing-logic-issue and starts a new mobbing session.
Under the hood, mob.sh has created a new branch off of fixing-logic-issue called mob/fixing-logic-issue. While Adam is making changes, they're going to occur on the mob/fixing-logic-issue.
Because the pair is working remotely, Adam shares his screen so that they're on the same page.
While on this branch, Adam writes a failing unit test that exposes the logic issue that he's running into. From here he signals that Brittany is up by running mob next
By running this command, mob.sh adds and commits all the changes made on this branch and pushes them up to the server. Once this command completes, it's Brittany's turn to lead.
Once Brittany see's the mob next command complete, she checks out the fixing-logic-issue branch and picks up the next portion of the work by running mob start
Because she was on the fixing-logic-issue branch, mob.sh was able to see that there was a mob/fixing-logic-issue branch already, so that branch is checked out.
Based on the test, Brittany shows Adam where the failure is occurring and they write up a fix that passes the failing test.
Though there are more changes to be done, Brittany has a meeting to attend, so she ends the session by running mob done, committing, and then pushing the changes.
By running mob done command, all the changes that were on the mob/fixing-logic-issue are applied to the fixing-logic-issue branch. From here, Brittany can commit the changes and push them back to the server.
Wrapping Up
If you're looking to expand your pairing/mobbing toolkit, I recommend giving mob.sh a try. Not only is the initial investment small, but I find the tooling natural to pick up after a few tries and since it's a wrapper around Git, it reduces the amount of learning needed before getting started.