The need to scale represents an aspirational challenge for growing organizations. While each company navigates distinct obstacles, recurring patterns emerge across the industry. Here are several considerations for decomposing a monolithic architecture to enhance service performance and engineering velocity.
🗿 Determine the Type of Monolith
Software systems encompass various monolithic structures, each requiring a distinct decomposition strategy. An application monolith with excessive responsibilities can be addressed by extracting high-volume or underperforming endpoints into independent services. A database monolith, where multiple services share infrastructure, necessitates decoupling data layers. A deployment monolith, characterized by lengthy build and release cycles, benefits from creating lightweight, independently deployable services.
👷🏻 Improve Your Operational Readiness
Successful decomposition demands robust infrastructure: continuous delivery pipelines, distributed system security capabilities, debugging tools, and monitoring solutions. As services multiply, deployment frequency increases, bug introduction becomes more likely, and observability complexity grows. Collaboration with DevOps/SRE teams helps standardize operational practices, while QA teams should prepare for increased testing complexity.
👥 Consider the Human Element
As monoliths fragment across teams, communication demands intensify. Decomposition enables focused domain ownership but requires stronger inter-team coordination. Services should reflect clear business or technical boundaries and warrant continuous evaluation of decoupling costs relative to velocity and scalability gains.
🛰 Choose When to Decouple
Decoupling decisions stem from technical, business, or product considerations. Technical decoupling addresses performance bottlenecks, while business-driven separation accelerates feature development velocity.
🛸 Build a Coalition
Large-scale initiatives require cross-functional alignment. Early stakeholder engagement, including engineering leadership, product, and executive leadership, ensures architectural changes integrate with broader business objectives.
🗺 Choose Where to Start
Begin decomposition with clearly definable capabilities. Services deeply embedded within monoliths prove harder to isolate. Services like authentication provide well-defined starting points for refining decomposition approaches.
“This was originally written as an answer to a case study I was given when applying for a Director of Engineering position.”