2019 will see the growing popularity of plenty of new and powerful approaches to building great APIs. Between growing amounts of data, a 21st century need-for-speed, and ever-tighter regulations, secure and effective API design is more important than ever — and we find that observing trends can be the best way to identify what’s working for others.

In this post, we want to give you an insight into five of the hottest API design trends that you should definitely be looking out for in 2019. Whether it’s developer experience to keep your API on top, GraphQL to meet clients’ dynamic needs, OpenAPI or AsyncAPI to define and document your message-based API, or OAuth and OpenID Connect to secure data delegation, we’re sure there’s a trend in here that you’ll want to hop onto!

1. Developer Experience (DX)

Trends in API Design Mindset

What is it?
First up on our list of API design trends is developer experience, which describes all aspects of a developer’s experience with an API. While the concept of user experience has been around for decades — encouraging developers to create a smooth and satisfying experience for users — developer experience is a somewhat novel development.

Perhaps it’s because developers are usually quite pragmatic (and understanding) when it comes to dealing with software, but developer experience has been a neglected field up until now. And that doesn’t make a lot of sense, since after all, developers are the true users of APIs — and they certainly deserve a smooth and satisfying experience.

Why does it matter?
Across industries, customer satisfaction is more important than ever. This is the result of globalization, growing economies, and the maturation of the Internet giving users more choice and thus higher expectations. Simultaneously, API practitioners have started viewing their APIs as bona fide products and treating them as such. Together, we think these factors will make developer experience a hot topic in 2019.

2. GraphQL Over REST

Trends in API Design Styles

What is it?
Our next API design trend to look out for in 2019 is GraphQL. GraphQL is an API design style that competes with REST, gRPC, Webhooks, and others. Until now, REST has been the most popular of the lot, but GraphQL is catching up quick.

GraphQL is characterized by its single, multipurpose “endpoint” which clients can use to retrieve whatever data they need, and only that data. In comparison, REST offers a multitude of set endpoints, which return a standardized response that is less customized to the client’s exact needs.

Why does it matter?
Though GraphQL is a little more complex than other styles — in the words of GraphQL co-creator Lee Byron it brings “more expressiveness and capability” to your API — it can be more efficient since it doesn’t send clients data they don’t need. With that being said, REST is still a powerful platform, and many individuals (including Byron) see the two co-existing.

3. OpenAPI

Trends in API Design Tooling

What is it?
Third on our list of API design trends is the OpenAPI specification. OpenAPI allows you to map out and describe the entirety of a REST API, from endpoints to authentication. Not only are specifications like OpenAPI an easy way to plan out APIs before you start building them, but they’re also an effective tool for maintenance, support, and the creation of developer materials (especially documentation and code).

Why does it matter?
Modern API design is all about speed and flexibility, and designing your APIs “to spec” has numerous benefits — planning, documentation, validation — with just one stone.

4. AsyncAPI

Trends in API Design Tooling

What is it?
AsyncAPI is a new kid on the block when it comes to API tooling. It’s a specification that allows you to create machine and human-readable definitions for your API, which makes it easy to generate documentation and even code. It was designed specifically for message-based APIs, drawing data from the messages themselves in a variety of protocols.

Why does it matter?
While AsyncAPI is similar to OpenAPI in what it actually does as a specification, the growing number of asynchronous, message-based APIs (for the Internet of Things and otherwise) has created a great demand for a more tailored solution.

5. OAuth (and OpenID Connect)

Trends in API Security Design

What is it?
The EU’s General Data Protection Regulation (GDPR) is now in full swing — and, if you haven’t already, it really is time to start taking the security of your API seriously. OAuth and OpenID Connect are two security measures you can’t go wrong with.

OAuth, which is now in version 2.0, is the open standard for granting applications access to a user’s data, without necessarily sharing their login credentials. OpenID Connect is an identity-centric authentication protocol that builds on the OAuth standard, allowing applications not only to verify the identity of the end-user, but also to gather basic information about them.

Why does it matter?
OAuth (and more recently OpenID Connect) is the golden standard for giving clients secure access to a user’s data in a transparent and controlled fashion. API security is now more important than ever, so why not opt for the tried-and-tested solution?

Final Thoughts

There’s a growing amount of data being shuttled behind the scenes, and users want faster access and greater security than ever before — or they’ll find an alternative. As a result, it’s essential for API owners and API practitioners to bear in mind the satisfaction of their developers, users, and regulatory bodies alike, by creating APIs that are indeed fast and secure. Whether it’s developer experience itself, GraphQL, OpenAPI, Async API, or OAuth and OpenID Connect, all five of these API design trends are about building a better product: a product that’s robust, efficient, and developer-friendly.