Here's the classic DynaComp compressor from MXR. This frequently cloned and copied effect has been an industry standard since it was introduced in the 70s. It uses the CA3080 IC, which can be a bit expensive and/or difficult to source as it is a rather obsolete chip. It might be a good idea to use tantalum capacitors in the place of the 1µ electrolytic caps for noise purposes. You can mount the pots directly to the board using either long leg right angle PCB pots or these more normal ones.
This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.