The growing complexity and power of the JavaScript ecosystem has recently made monorepos popular as a way to collaborate across teams, increase developer mobility and solve the pains of shared library versioning. But because of how large they can grow, the architecture can quickly get messy and CI times can increase exponentially.

In this talk we’re going to look at what monorepos are, what problems they solve, pitfalls to watch out for, and then see how different tools can step in and make working in monorepos a delight. We’ll eventually focus in on the open source project Nx, which allows you to automate how your architecture is allowed to grow in a monorepo, and, with its deep knowledge of your project graph, it can optimise CI times, keeping them constant, sometimes making them faster, and in some cases, almost instant.