npm install
npm start

App would be available at http://localhost:3000.

• Create columns (with add column button).
• Create cards (with add card button).
• Edit cards (with ✏️ button).
• Delete cards (with 🗑 button).
• Edit columns (with ✏️ button).
• Delete columns (with 🗑 button).
• All editable fields save info on blur, click outside or pressing enter. Pressing escape would cancel changes.
• Drag and drop cards between columns.
• Store data in local storage.

• Drag and drop cards within columns.
• Drag and drop columns.
• Confirmation dialog when deleting cards/columns (or undo).
• Responsive design, I didn't focus on it, and it's not working well on mobile.
• Some kind of validation. Probably cards and columns should not be empty.

• Add tests. I didn't add any tests, because I didn't want to spend too much time on this project. But in real life project, I would add tests for application - probably using Cypress. I don't think that unit tests are really helpful inside of projects - I believe that you should cover your libraries with unit tests and use e2e tests inside your application. Of course there are exceptions, like utility-like functions, complex logic, etc.
• Obviously in real life I would not consider to use self-written store manager. I would choose Redux.
• Again, in real life I would not try to implement drag and drop by myself. Even if none of existing libraries would fit my needs, I would write all the logic for drag and drop in separate library, and then use it in my application. I would also write tests for it.
• Probably some kind of CI/CD would be nice to have. Different tools can be used for it, it depends on the company, and it's infrastructure. For personal projects I usually use GitHub Actions, but in my current company we use Jenkins and Bamboo (mostly because it can be self-hosted).
• Backend :-)

App functionality:

• A user should be able to add and label columns.
• A user should be able to add and edit cards.
• A user should be able to move cards between columns (UX is up to you, does not need to be drag-and-drop).
• Do make sure the available interactions are intuitive. In other words, we will be considering usability.
• Some kind of persistency (LocalStorage or SessionStorage) is encouraged, though not required.
• Any additional features you find important (feel free to elaborate in your README file about why you made certain choices).