While create this project I came across many errors, because there are no proper examples available on the internet, hours are spent fixing the bug, you may get small patches like how to use passport for login registration but that example may be not using same packages like us, so it will be hard to understand and modify according to your packages, again you have to search for v2 coding where you are using async await but there are very few examples available, you will get v1 examples more for koa.
While using async await you should be careful, don’t use too many await it will throw error, you should know where to use await and where not. While routing don’t redirect too much it will throw to-many-redirects error on browser and you have to clear your browser cache, remove redirects and then run the project.
If you are used to generator functions then try to use co.
You can go for testing using mocha, supertest, you should simultaneously run test project you will find easy to understand your project. Use try catch for handling errors, in db queries use function(err,data) in callback so you will know you are getting data or not. Be proper with declarations, names and be sure all packages are installed. Check for terminal every time you run your project and while rendering pages on browser.