[nickjj]

> I would say Flask is genuinely really difficult to use. It's very easy to start with but the moment your project becomes non-trivial

Do you have specific examples?

I've built a number of decently large Flask apps over the years (dozens of blueprints, 100+ models, etc.) and it was never an issue. I've used similar code organizational patterns in both small and large apps and it worked great. It was a combination of solo projects and working with small teams.

[WD-42]

I share OP's general statement. I've been using Flask and Django on and off for near a decade.

When deciding between Flask and Django, I look at the following requirements:

User accounts

Object Relational Manager

Database Migrations

User registration/social authentication

Admin Site

As a general rule of thumb if my project is going to need 3 or more of these things I just go with Django.

You CAN do all of that with Flask, but you end up wiring together a bunch of third party dependencies just to end up with what Django would have provided you out of the box.

[zippergz]

FastAPI doesn't (directly) help with most of these either, so that's really a Flask vs. Django comparison rather than Flask vs. FastAPI.

[aniforprez]

> solo projects and working with small teams

As I said, any time a Flask app becomes non-trivial, it's a pain. Engineering scaled up from 10 to 30 and immediately it was apparent what a massive pain it all was. We had to implement auth, access control, caching, API documentation, admin panel etc etc all on our own. Flask plugins are very fickle with a lot of them not being maintained anymore that don't fit our use cases. If you need all these things in a customer facing app, you might as well just use Django. Performance suffers a little but the ease of developer onboarding and batteries included in the framework, coupled with a lot of well maintained popular plugins honestly make Django the de facto choice for web app dev that needs to scale. Flask is good for small services being maintained by small teams

[nickjj]

> As I said, any time a Flask app becomes non-trivial, it's a pain

Results may vary. Small teams doesn't mean small apps. You can have 150 models, dozens of screens, caching, background jobs, rate limiting, multiple payment providers, multi-tenancy, public APIs and other features you would expect in a decently sized SAAS app and it's fine. The popular Flask extensions for certain behavior are pretty well maintained. There's also a number of Python libraries that can get used in a Flask app that aren't specific to Flask but are very well maintained like SQLAlchemy and Celery.

I wouldn't say Flask is better than Django or Django is better than Flask but I think you can be wildly successful building an app with either one. It comes down to personal preference. Your post made it seem like Flask is some graveyard of dead libraries and you can't build anything successful with it but that's not the case.