I had to code a feature in one of the services that essentially made a simple SQL call every x minutes to check up on something. The amount was supposed to be c

I had to code a feature in one of the services that essentially made a simple SQL call every x minutes to check up on something. The amount was supposed to be configurable. I put 20 minutes as the default config and everything seemed fine. Next week I found out that I took down prod because the service made calls every 20 milliseconds instead of every 20 minutes. I remembered to convert "20" to an actual time representation but I accidentally used the unconverted value anyway and it turned out there's an another constructor for the method I used to execute the SQL query and it accepts integer values as well and treats them as milliseconds. What's weird is that this version of the service was running for a week in our test environment and absolutely no one noticed the degraded performance. A temporary workaround was to change the value in the config to 1200000. It taught me the importance of having configurable values in the application as we'd have to build and redeploy it again if the value was hardcoded.