I recently built a new mixer for my eurorack drum machine. I was previously using an outboard compressor to process the drum machine which was quite inconvenient and very noisy, so I picked a design with a built-in compressor, Hexinverter's Mutant Hot Glue.

The module is available as PCB and panel set from various retailers. It's a VCA design with a few somewhat rare silicon items. In this video I compare its design and sound to the compressors I was using previously - the Wampler Ego V2 as well as the FMR Really Nice Compressor, which uses a very similar circuit.

This module also has a built-in distortion and send/return feature, which I will make use of by adding a dedicated reverb/delay to the rack.