Flask

Judgement

What it is

Framework or platform

What it does

A lightweight Python web framework built on Werkzeug and Jinja for building web apps and APIs, extended through a large set of extensions.

Adopt it when

You want a minimal Python web framework where you choose your own database and components.

Watch out

You assemble auth, ORM and admin yourself, and it is synchronous by default.

Ready for

Production-ready

Runs as

Library

Built with

Python, Werkzeug and Jinja

How established

Established: started 16 years ago, latest release 3.1.3.

What the license allows

You can build it into a product you sell, as long as you keep its copyright notice.

Judged on 2026-11-03 from the project's README and GitHub data. The license and age lines are worked out directly.

Built from

Follow it down: Flask → CPython → GCC → LLVM project → runs on a microchip

How compilers were built, back to punched paper tape

Built on Flask: 9 projects

1. 1
   Mongo mongodb

   The MongoDB Database

   Building block Production-ready Your data is naturally document-shaped and changes structure often, or your team already knows MongoDB.

   ★ 29k See repository C++ Active, pushed today
2. 2
   Authlib authlib

   The ultimate Python library in building OAuth, OpenID Connect clients and servers. JWS, JWE, JWK, JWA, JWT included.

   Building block Production-ready You implement OAuth or OIDC in Python, either consuming providers or running your own server.

   ★ 5.4k BSD-3-Clause Python Active, pushed today
3. 3
   OSWorld xlang-ai

   [NeurIPS 2024] OSWorld: Benchmarking Multimodal Agents for Open-Ended Tasks in Real Computer Environments

   Developer tool Usable You research or build computer-use agents and need a standard way to measure them.

   ★ 3.2k Apache-2.0 Python Active, pushed today
4. 4
   privacyIDEA privacyidea

   :closed_lock_with_key: multi factor authentication system (2FA, MFA, OTP, FIDO Server)

   Complete system Production-ready An organisation needs on-premises MFA across VPNs, Windows logins and applications under its own control.

   ★ 1.8k AGPL-3.0 Python Active, pushed today
5. 5
   TimeTracker DRYTRIX

   Self-hosted time tracking & invoicing for freelancers and teams: timers, projects, PDF and Peppol e-invoicing. Open-source Toggl/Clockify alternative.

   Complete system Usable A European freelancer or small firm needs time tracking and Peppol-compliant invoicing on its own server.

   ★ 634 GPL-3.0 Python Active, pushed 6 days ago
6. 6
   KeyLeak Detector Amal-David

   Runtime leak detector for modern web apps - finds exposed API keys, validates BaaS misconfigurations (Supabase/Firebase RLS), and catches secrets in JS bundles. Chrome extension + CLI.

   Developer tool Experimental You ship web apps on Supabase or Firebase and want to check your own app for leaked keys and open row-level security before launch.

   ★ 274 MIT Python Active, pushed 4 days ago
7. 7
   DataGerry DataGerry

   Enterprise-Grade OpenSource CMDB with flexible data model.

   Complete system Usable You need an asset or configuration database with a data model you design yourself rather than a fixed ITIL schema.

   ★ 190 AGPL-3.0 Python Active, pushed 13 days ago
8. 8
   REMS-For-Organisations bearlike

   🚀 Streamline club management with our all-in-one system: bulk mailer, certificate generator & more. Perfect for student organizations.

   Complete system Usable A student society needs event certificates and mailings without paying for several SaaS tools.

   ★ 162 MIT HTML Active, pushed 8 days ago
9. 9
   ChatGPT Clone xtekky

   ChatGPT interface with better UI

   Template or starter Experimental Only as a learning example; maintained alternatives are far better.

   ★ 3.5k GPL-3.0 Python Quiet, pushed 2 years ago

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1. 1
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2. 2
   Flutter flutter

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   Framework or platform Production-ready You want one team to ship polished apps on mobile and desktop from a shared codebase.

   ★ 181k BSD-3-Clause Dart Active, pushed today
3. 3
   FastAPI fastapi

   FastAPI framework, high performance, easy to learn, fast to code, ready for production

   Framework or platform Production-ready You build JSON APIs or ML services in Python and want typed, async code with free docs.

   ★ 104k MIT Python Active, pushed today
4. 4
   Angular angular

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   Framework or platform Production-ready You build large enterprise web apps and want a complete, opinionated framework with long-term support.

   ★ 101k MIT TypeScript Active, pushed today
5. 5
   Django django

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   Framework or platform Production-ready You are building a data-driven web app in Python and want batteries included.

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6. 6
   Svelte sveltejs

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   ★ 89k MIT JavaScript Active, pushed today
7. 7
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   Framework or platform Production-ready You want the most widely known, unopinionated Node.js server framework.

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8. 8
   Rails rails

   Ruby on Rails

   Framework or platform Production-ready A small team wants to build and ship a web product quickly with one cohesive framework.

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