
Find potential bugs in your services with Diffy - hiby007
https://github.com/twitter/diffy
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jawns
This is a cool approach to finding bugs in non-deterministic services.
Basically, each request is played against three servers: one running the code
to test, and two running known good code. If the variation in responses
between test:good is no different than the variation between good:good, you
can assume that no regressions are present.

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spullara
When we moved the Twitter web frontend from the RoR stack to the Scala stack
we used a similar tool built into the proxy we called Tap Compare. The new
thing in Diffy is to use two calls to known good services rather than one call
to filter out the non-deterministic bits. With tap compare we basically had to
whitelist those parts of the page. This kind of strategy is pretty powerful
and you will likely find lots of places in your infrastructure where it makes
sense to use it.

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masukomi
ahem "Build failing"....

not the greatest way to start off my interaction with a tool that's supposed
to find bugs.

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masukomi
coverage 13% doesn't help much either.

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khanduri
We've been using diffy to test diffy :) Just kidding. Contributions welcome.

