So I recently found out that just about every other company in this town pays their devs with equivalent experience at least 25% more than what my current employer does.

I requested a salary meeting and informed my boss that I'm way below the average for my position, he replied "Yeah, your salary has been below average for years now, yet you are my best employee in this area".

It hurts that he very well knew this fact and still decided not do to anything about it before I brought it up.

I told him that I don't feel rewarded for all my hard work and overtime, so I requested a 25% bump or I'm leaving in January.