Before you upgrade to Catalina, the next version of macOS, make sure you run this tool from St. Clair Software. It will tell you the last time you ran an app that isn't 64-bit. Chances are, something you rely on will show up.
When I ran the tool, I found 11 apps that I use at least occasionally that either are not 64-bit compatible. I didn't see any dev tools in there but my older Adobe versions are all not compatible. For some, I just am running an older version and just need to update, but others are just not being updated anymore. Make sure you know what you're getting into before you install!
There are significant changes with this year's Mac update, including the fact that Catalina will no longer not support 32-bit applications.
Auditing Your Mac for 32-Bit Applications and Go64 by David Sparks