New in Yeller: Suspect Deploys

This is a blog about the development of Yeller, The Exception Tracker with Answers

Read more about Yeller here

Most exceptions are caused when your system is changed. Much software, if it is left completely unchanged, will not suffer any new exceptions. As such, when you’re debugging an exception, often the first thing you’ll look at is “what changed before this exception”.

So, Yeller gets a new feature today, that labels the suspected deploy for any exception. It includes a link to github’s compare view (if you have a github project configured), so you can read an exact diff on what changed. Here’s what it looks like:

It’s fairly simple, but I’ve already found it extremely useful for making me actually look at the diff of what was deployed.

The Importance of Ease

One of many things I learned from Matt Might, is that as humans are fundamentally optimized to go for lower effort solutions, making things close at hand is important. Matt uses this to illustrate why you should have a pullup bar in your office doorway - if it’s there, you’re likely to do more exercise.

Similarly, Yeller’s prinicple of ease, is that all the debugging information you need is right at your fingertips. If you don’t have it there, often you’ll guess at what the cause of the exception was, and not do rigorous analysis.

If you don’t understand why something is happening you can’t fix it.

If you didn’t fix it, it ain’t fixed

Artur Bergman (CEO of Fastly)

Often this turns out well - developers often know the systems they work on well enough that their best guess as to the cause of an exception is accurate. Yeller aims to get all the analysis information you need right there at your fingertips, so you don’t have to jump around between 4 different tools to figure out the root cause of an exception.

Of course, some kinds of analysis will not happen on a hosted service - Yeller can’t exactly point strace at a running process and analyse what’s going on (for example). But for the common case, looking up diffs, looking through the other data with an exception, and many other cases, I’m going to put all that right in your face, so you look at it.

This is a blog about the development of Yeller, the Exception Tracker with Answers.

Read more about Yeller here

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