Imagine the technical debt of a startup in exponential growth for 6 consecutive years (5 engineers to 160, 10M daily events to over 70B). Until the last 2 years the team focused on product expansion with an “if it ain't broke don’t fix it” attitude, resulting in inherent bugs, system instability & more than 80% of the team's focus on maintenance. This will be a tale of how we went all-in on reducing technical debt by allocating more than 70% of the team for 1.5 years to reduce debt. I will share how we rewrote our core engine; almost 2 years into the process we managed to reduce the maintenance effort, number & severity of production issues & increased our velocity significantly. It was all possible due to a craftsmanship culture we’ve been cultivating which grew stronger with the process