Realm Blog

Serverless Logic with Realm: Introducing Realm Functions

Today we’re announcing Realm Functions, a new part of Realm that makes building server-side functionality a lot easier for mobile developers. Now, you can make server-side features without enlisting backend developers, plus you get all the benefits of building on top of the Realm Mobile Platform: you don’t need to add another endpoint to a server, and then write the serialization and networking code that would let you connect with it. You just connect your app to Realm, write a Realm Function in your web dashboard, and watch your code execute reactively as data streams in. Today’s release is a beta, and it’s available today to everyone, whether you’re building an app in an enterprise-scale team or for a small side project.

Performant data storage and realtime data synchronization are important parts of building a great app, but there’s an endless world of possibilities when you can add custom logic to your server. You can write functionality that needs to be protected from tampering, call and coordinate countless other APIs, or use your app’s aggregated data to power machine learning systems. Unfortunately, sophisticated server-side features are hard to build, and hard to integrate with your mobile apps. Even a basic streaming API requires lots of work from the backend developers who will build out the server-side code, and a lot of attention and maintenance so that your apps and server can communicate the data your users need.

Write code that does work, not code that makes work

Realm is deeply committed to getting rid of the roadblocks between you and great apps — and up until now, the bulk of our work has revolved around data. The data you work with in your apps should be easy to save, easy to sync, and easy to respond to as it changes — wherever it changes, and whoever changes it. With Realm Functions, we aim to make it just as easy to create the logic that your app is built on so that you can focus on delivering hard, important features.

In our web environment, you simply write JavaScript to perform the tasks you need, and you’ll instantly see the results as data pours in and your code runs reactively in response. You can breathe a sigh of relief, as adding more features doesn’t also mean adding more fragility and maintenance to your app: you don’t have to add any new serialization or networking code to make a Realm Function work, as the Realm Mobile Platform takes care of getting data to connected clients.

Try out Realm Functions

To show how easy it is, we added a cool new feature to our Realm Tasks app. When you create a task that has a time or date in the title, we’ll use a natural language processing API to turn that into a due date on your task. We did it with just a few lines of code in the app to display the reminder, and a few more lines of JavaScript to call the NLP API and update the Task object. Check out the video, and continue below to get started yourself.


To try it out yourself, just head over to our Realm Tasks repository and follow the instructions there to get started with the Realm Mobile Platform and Realm Functions. Or if you’d like, you can jump right to the Realm Functions documentation.

Realm Functions is a powerful way to add server-side logic to your app through a simple web interface. All Realm Mobile Platform users get access to the Realm Functions beta, and you can start using it today. Today’s beta release lets Developer Edition users try Realm Functions for free with up to three concurrent running Functions; Pro and Enterprise Edition customers have an unlimited number of Functions they can implement. We’re excited to see what you can build using Realm Functions!

Realm Team

At Realm, our mission is to help developers build better apps faster. We provide a unique set of tools and platform technologies designed to make it easy for developers to build apps with sophisticated, powerful features — things like realtime collaboration, augmented reality, live data synchronization, offline experiences, messaging, and more.

Everything we build is developed with an eye toward enabling developers for what we believe the mobile internet evolves into — an open network of billions of users and trillions of devices, and realtime interactivity across them all.

Get more development news like this