manifest.yml is a YAML-formatted configurations bundle for Slack apps. With a manifest, you can create an app with a pre-defined configuration, or adjust the configuration of an existing app.
app.js is the entry point for the application and is the file you'll run using node to start the server. The project aims to keep this file as thin as possible, primarily using it as a way to route inbound requests.
The folder contains all the documentation for the project, like this file.
Every incoming request to Tasks App is routed to a "listener". Inside this directory, we group each listener based on the Slack Platform feature used, so /listeners/shortcuts handles incoming Shortcuts requests, /listeners/views handles View submissions and so on.
All user interface in a Slack App is expressed using Block Kit. This folder contains all the Block Kit code for the app. For ease of reading, Tasks App uses a community library called Block Builder, but this isn't a requirement of Slack Apps. You're free to use a different library such as JSX Slack, or even regular JSON. The Slack Platform endpoints consume blocks as JSON, so whichever approach you take, as long as it can output valid Block Kit JSON, will be fine.
To make it easier to switch between data store types, we use Sequelize to handle all the database interactions. By default we use SQLite to simplify local development, but any of the systems that Sequelize supports should work. The /models folder contains the structure of all the data objects used.
These are files related to the database migrations performed with Sequelize. These migrations should be the only way that the structure of the database is changed.