Polar

Judgement

What it is

Complete system

What it does

A merchant-of-record billing platform for selling subscriptions, digital products and usage-based plans, handling payments and sales tax.

Adopt it when

You sell software or digital products internationally and want tax handling and billing done for you.

Watch out

Merchant-of-record means a percentage fee on each sale, and the hosted service is the real product even though the code is open.

Ready for

Production-ready

Runs as

Cloud service

Built with

Python, FastAPI, TypeScript and Next.js

How established

Established: started 3 years ago, latest release @polar-sh/better-auth@2.1.3.

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.

Compare Polar

Built from

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

How compilers were built, back to punched paper tape

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