Yes, indeed. You need to go first to the IDE on your browser and login with your account: https://graph.api.smartthings.com/login/auth
Then you go to the “MY Device Handlers” tab and click on the green button to create a new device handler.
Then go to the “From Code” tab and there just copy and paste the code from here: https://github.com/mitchpond/SmartThingsPublic/blob/master/devicetypes/mitchpond/quirky-wink-tripper.src/quirky-wink-tripper.groovy
Then you click on create. On the next page you click on “Save” and then on “Publish” and choose “For me”. And that’s it.
After that just go to the Marketplace in the app, connect a device and it will recognize it.
Here’s an official overview for the custom code by the great JD: FAQ: An Overview of Using Custom Code in SmartThings