Helpful tools for building custom Slack apps

From prototype, to deployment, here are our favorite tools for the custom Slack app builder

Illustration by Sarah Lazarovic

Building a great Slack app is more than just connecting to APIs. You also want to prototype your workflows, eye up your interactive messages, and rapidly iterate your code.

Here a few tools that can help you map out your integration’s workflows before writing a line of code.

Preview your app messages with the Slack Message Builder

Slack’s message builder is a simple tool built right into our online documentation, enabling you to preview what your app’s messages will look like to users.

You can write the JSON of your message and the message builder will preview the message in real time as it’ll appear in Slack. You can toggle between a few pre-built JSON examples that are easy to tweak and adjust — for everything from simple messages to complex attachments with interactive buttons and message menus.

Prototype workflows with automation tools

Building a fully-functioning app doesn’t always require a web host – or even any code. Automation tools like Zapier or Workato make it easy to put together integrations that connect Slack to other systems you’re already using, like calendar software, social media trackers, form responses, or project management tools.

You can use these workflow builders as a way to test ideas for processes on your team before committing to writing a line of code. You may even discover that just connecting services together means you don’t need to code an app at all.

Get to coding faster using Ngrok

When it comes to building your app, sometimes the hardest part can just be getting started. One tricky piece that can eat up a lot of time: getting your code deployed to a public web server accessible by Slack’s APIs.

If you’re ready to code on your local computer and just need a way to set up an endpoint that Slack can access, try a tunneling tool like ngrok. Ngrok allows you to create a secure URL in an instant, meaning you can test your requests directly from your machine without constantly redeploying your work to a hosting platform or webserver. (We even wrote a tutorial on using ngrok with the Slack API.)

Remix existing Slack apps on Glitch

If Node.js is your tool of choice for building Slack apps, take a look at Glitch to get started.

Glitch is a platform for hosting fully self-contained Node.js projects. The projects run on virtualized backend, letting you edit code right in the browser. That means you can take an existing project, then “remix” or modify it for your own team, all without needing to provision servers or deploy your code.

Getting started couldn’t be easier since there’s nothing to install, and there are a number of Slack apps you can remix and make your own — including a Slack starter kit that anyone can use.