Presentation: Front-End APIs: Powering Fast-Paced Iterations

Karthik: I work for the Application Infrastructure team at LinkedIn. Specifically, I lead the mobile infrastructure team.

Our team designs and builds shared libraries (examples include networking, caching, image loading, analytics, performance instrumentation etc.) and tools (build, debug and test tools) used by all native mobile applications (iOS/Android) at LinkedIn. Since our mobile clients are thin, we also focus a lot on the server-client interaction. This includes but is not limited to, the structure of the API exposed by the server, the wire format, compression algorithms to use when communicating between client and server etc.

Aditya: I lead the infrastructure development for the frontend API server, which powers the LinkedIn app on iOS, Android and Web. Our team is focussed on laying down the foundation of our frontend API server, its overall architecture, modeling direction, testing strategy. Our team is also responsible for developer happiness and operational stability of the service. This drives us to push the boundaries on coming up with innovative ways to enable application teams to ship features as fast as possible with stable infrastructure

Karthik: LinkedIn has massive scale (in terms of user base), as well as significant complexity in the structure of APIs we expose to our clients on account of diverse features. In addition, we also move fast and release new code to our API server/web clients multiple times a day, and mobile apps once a week. A huge army of developers, designers, site reliability engineers, product managers, engineering managers, project managers work smoothly in tandem to make this happen. Since the product moves so fast, designing an API that evolves elegantly and minimizes engineering work for adding new features, while being relatively stable is crucial.

This talk charts our journey along various approaches for API design that we’ve explored, our missteps and learnings at each stage, where we are now and a sneak peek into our future direction.

Aditya: The talk is going to be around the evolution of how we started with entity-based modeling. This is where you describe an entity that's sent to the client and then the client does the transformation. We are moving from this approach to a place where we have our own language that the client can use to stitch everything together as it needs. The talk will have what we've learned from this approach, and how it helps us shoot for shipping features to consumers without making client-side changes. The goal is to monitor and power these experience directly from the server side.

Karthik: How to design and structure APIs that can evolve quickly to support various client UI use cases, while making minimal/no changes to client side code to support these new use cases.