Flask in
Production

Instagram launched in 2010 on a Python/Django stack running on EC2. By the time Facebook acquired it in 2012 for $1 billion, it served 30 million users with 13 employees and zero engineers dedicated to scaling. The lesson: simplicity isn't a liability. It's a competitive advantage.

Their engineering blog is explicit: they chose Python because it was readable, productive, and let a tiny team move fast. Not because it was the most performant option — because developer speed mattered more than raw throughput.

Pinterest used Flask for their API layer at scale. Their engineering team wrote extensively about their Python microservices architecture — Flask routes, PostgreSQL, and a CDN for static assets. Their monthly active user count crossed 100 million while still running Flask.

They open-sourced several Flask-related tools and wrote detailed blog posts on running Flask in production with gunicorn, gevent, and nginx. The same stack you'd deploy today.

LinkedIn has used Flask for internal tools, data pipelines, and microservices across their engineering organisation. Their data engineering team built multiple production Flask services for internal analytics and data quality tooling — serving hundreds of thousands of internal requests daily.

This is one of Flask's strongest use cases: internal tooling. Fast to build, easy to maintain, and the "performance" bar is lower for internal users who accept a 200ms load time without complaint.

Airbnb's data platform and multiple internal microservices run on Flask. Their open-source tools — including parts of their data engineering pipeline — are Flask-based. They also built Superset, the analytics platform, on top of Flask (it still uses Flask at its core today with 60k+ GitHub stars).

Netflix uses Python extensively in their engineering and security infrastructure. Their open-source security tooling — including parts of their chaos engineering platform — run Flask. The Netflix Tech Blog has documented Python microservices as a key part of their tooling ecosystem.

Netflix doesn't use Flask for streaming video (that's a different beast entirely). But for internal tooling, security tools, and data services? Python + Flask is standard. Even Netflix knows when simple is right.