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Session + Live Q&A

Building With Extensibility

Extensibility isn't just making your endpoints public; you should think about how your product will be extended and enhanced by others before you write a line of code. Gain an understanding of why we want to build extensible products rather than just checking off a "public API" box. In this session, you'll learn how to build a truly extensible product and create a delightful developer experience.    

This presentation will cover concepts of extensibility rather than diving deep into technical details, so will be relevant to anyone who works on software, including engineers, product managers, and designers. You will also hear why it's important for all of these roles to gain an understanding of extensibility and consider it at each step of the product lifecycle.

Main Takeaways

1 Hear why it is important to consider extensibility from the beginning, and why all the team needs to be involved.

2 Learn some of the principles of extensibility.

What is the work you're doing today?

Today I work at Square in the Square Seller organization, which is what everyone knows externally as "Square", with some other organizations being Cash App and TIDAL. I work on the developer's extensibility team, which means I help develop the parts that internal and external developers use to interact with Square. So, I work on things that make our external APIs better as well as things that the internal teams can use to build out their public APIs - like webhooks, OAuth, and the APIs themselves.

What are your goals for this talk? What do you want people to walk away with after the talk?

I've been working on extensibility for my entire career, and it's really something that you need to think about throughout your project, it's kind of like mobile first. If you're going to build something that has a good mobile experience, you need to think about that from the beginning. If you want to build something that's extensible, you also need to think about extensibility from the beginning, because that can really influence architecture and the way you build the app. What I mean by that is if you want an external developer to be able to work with your product in a truly extensible way, not just like, I have public APIs for my internal endpoints, they will be able to tie into your product in a way that makes it feel like you really thought about it and they are basically like a first party.

An example of this might be if you have a web page where you are showing some first-party data and you want the third party's data to show up and look just like your data. This might mean the end user wouldn't even necessarily notice that there's any third party involved, which could be the best user experience for that end user.

Who's the audience for the talk?

Architects and lead developers. It is really, in my opinion, something that the entire team should be involved in so I think this kind of information is relevant for anyone on a team, but particularly architects and lead developers should be thinking about this as they're designing the system, as they're creating stories, and giving technical requirements.


Christi Schneider

Software Engineer @Square

Christi recently became a software engineer at Square's office in Atlanta. She works on the extensibility team, building the tools and establishing patterns that other Square teams use to build the external developer program. Before Square, she worked at Blackbaud as a part of many teams over...

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Tuesday Nov 9 / 12:10PM EST (40 minutes)


API Architecture



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