REST, GraphQL, or gRPC? It’s not just a tech choice — it’s a trade-off between flexibility, performance, and long-term scalability. Here’s a no-fluff comparison of REST, GraphQL, and gRPC — why it matters, and when to use each. REST REST uses HTTP methods over HTTP/1.1 to expose resources via URLs. It’s stateless and often the default for public APIs. Use Cases: - CRUD-based applications - Public or third-party APIs - Traditional web apps - Systems that benefit from HTTP caching Pros: ✔ Simple to implement ✔ Wide tool and framework support ✔ Stateless and scalable ✔ Leverages HTTP caching and auth Cons: ✖ Over-fetching or under-fetching data ✖ Poor fit for complex nested queries ✖ Not built for real-time scenarios GraphQL GraphQL flips the REST model. Instead of multiple endpoints, there's one — and clients define the data structure they want. Use Cases: - Mobile-first or bandwidth-sensitive clients - Complex data relationships - SPAs that evolve quickly - Aggregating multiple data sources Pros: ✔ Avoids over-fetching ✔ Strong typing and introspection ✔ Flexible and precise queries ✔ Great for frontend-driven architectures Cons: ✖ Harder to cache ✖ Higher learning curve ✖ Needs care to avoid performance issues ✖ Rate limiting is non-trivial gRPC gRPC is Google’s high-performance RPC protocol built on HTTP/2 and Protocol Buffers. It's built for internal service-to-service communication. Use Cases: - Internal microservices - Real-time data pipelines - Low-latency environments - Polyglot systems (multi-language) Pros: ✔ Fast, compact binary protocol ✔ First-class support for streaming ✔ Strong contracts with protobuf ✔ Ideal for high-throughput systems Cons: ✖ Not browser-native ✖ Binary makes debugging harder ✖ More setup complexity ✖ Smaller ecosystem than REST So which one? - REST works when you need simplicity, maturity, and broad compatibility. - GraphQL is ideal when the client needs flexibility and precise data control. - gRPC is the performance-first choice for, low-latency service communication. The protocol isn’t the goal. Your context decides the trade-offs. But choosing the right one makes building the right system easier. I'm curious — which one are you using most right now, and why? Follow Lahiru Liyanapathirana for more content like this.