When Greenlight had 30 engineers and a single monolith, it was possible for everyone to understand the entire context of the product. Engineers could get together to discuss a potential change and be confident in their understanding of the consequences and potential blast radius if things went wrong. Now, at around 300 engineers and 30+ microservices in production, it’s challenging for any one engineer to feel confident in either of those things. Tracking down who has knowledge of what can quickly lead to a “design by committee” failure case. How do we make sure that the decisions we are making won’t negatively affect other systems while continuing moving forward fast?

At Greenlight, we’ve implemented a framework of Decision Logs and Technical Specs that, coupled with strong principles on ownership, increases cross-team awareness of impactful decisions that are being made across the engineering organization.

In this talk we will explain how the framework works, how it was first introduced by the Infrastructure and Operations group, its benefits, and some of the challenges we found while implementing it and getting it adopted in other parts of the engineering organization.

By the end of the talk attendees will know whether incorporating some of these patterns into their organizations would help with scaling their engineering teams and how to get started, learning from our wins and our mistakes.