So I am running Ubuntu 18.04 as my desktop machine on my new laptop. I am using this primarily for development.
Some services I want to use are using older versions like redis, go progrmaming language versions etc. I end up googling around and this usually requires me to manually install or add repositories etc. if I use apt.
What are the ramifications if I use homebrew?
I didn't realize it works on linux. Will this cause potential conflicts with apt related packages?
The current LTS (18.04) is nearly two years old. Since Debian and Ubuntu use a snapshot release model (not a rolling release model) most of the software in those two-year-old repositories will be --you guessed it-- of roughly equivalent age. This related question explains in much more detail.
For newer software, try a newer release of Ubuntu. Most Ubuntu developers that I know use the latest release, not the LTS. It depends what you are developing for.
Homebrew installs to a different location than apt or pip or other common package mangers, so conflicts seem to be rare. However, most package mangers only keep track of their own packages, be prepared for a bit of bloat as many of your libs are promptly duplicated in the new location.
Dependencies installed by Homebrew CANNOT be used for Deb packages - only deb dependencies can be used for debs.
Dependencies installed by Homebrew CAN be used for Snap packages, though it will take a bit of work since current snap tools don't look for Homebrew packages.
Homebrew has their own support site also.