Have you ever caused downtime of your production due to a bad migration?
Maybe you've forgotten to add index concurrently to your huge table and locked it?

Our applications very often make use of relational databases – and from time to time we need to change their schema. These operations usually take just a few lines of code – but when not used correctly can cause a long and painful downtime of your production.

I've created an open source library excellent_migrations. It's a static analysis tool for checking safety of database migrations. It automatically detects potentially dangerous or destructive operations. the tool analyses code by traversing Abstact Syntax Tree (AST) of migration files. It also provides a mechanism to silence certain checks, when you are sure that you know what you're doing.

In my session I'll talk about unsafe operations, how excellent_migrations lib works why it's fun to do open source.

GitHub repo: https://github.com/Artur-Sulej/excellent_migrations