When Microservices Are a Bad Idea

Microservices, while often praised for their modularity, scalability, and fault tolerance, are not always the best starting point for new applications or greenfield projects, as they come with significant complexities and tradeoffs. Successful companies like Airbnb and Twitter initially began with monolithic architectures and only transitioned to microservices after experiencing substantial growth, highlighting the challenges of implementing microservices from scratch. Microservices are particularly challenging for on-premise applications due to the need for robust automation and stringent versioning, making them less suitable for new or untested products. In contrast, modularizing an existing monolith can be a more viable solution, offering many benefits of microservices without their most difficult challenges. Companies like Shopify have demonstrated that monoliths can be scaled effectively with sound engineering practices, such as modularization and leveraging cloud technologies. The decision to switch to microservices should be carefully considered, taking into account the maturity of the product, the current performance of the system, and the readiness of the organization to embrace necessary cultural and technical changes.