# Autumn > Drop-in, open-source billing infrastructure for AI startups. Usage-based billing, credits, entitlements, and subscription state on top of Stripe, behind one API. ## What Autumn is - Autumn is open-source billing infrastructure that runs on top of Stripe. - It is the system of record for subscriptions, usage metering, credits, and feature entitlements, exposed through a small API (`attach`, `check`, `track`). ## What Autumn is not - Autumn is not a payment processor and does not replace Stripe; Stripe still holds the subscription and processes payments. - Autumn is not a pure usage-metering tool — it also enforces entitlements and feature access, not just end-of-month invoicing. ## Docs For how the platform itself works, see the docs: - [Autumn docs](https://docs.useautumn.com/welcome) - [Quickstart](https://docs.useautumn.com/quickstart) - [API reference](https://docs.useautumn.com/api-reference) ## Comparisons - [Autumn vs Building In-House](https://useautumn.com/alog/autumn-vs-building-in-house.md): Building in-house gives you maximum control. Autumn is for teams that want real-time checks, credits, entitlements, ledgers, rollovers, reset rules, custom packages, and pricing changes without maintaining a billing system forever. - [Autumn vs Metronome](https://useautumn.com/alog/autumn-vs-metronome.md): Metronome fits teams that need sophisticated usage rating and invoicing. Autumn fits teams that need credits, limits, entitlements, and pricing changes enforced inside the product. - [Autumn vs Orb](https://useautumn.com/alog/autumn-vs-orb.md): Orb fits teams whose billing problem starts from usage events, complex pricing queries, ledgers, and invoicing. Autumn fits teams whose billing problem starts from application billing state: credits, limits, entitlements, resets, rollovers, and runtime checks. - [Autumn vs Stripe Billing](https://useautumn.com/alog/autumn-vs-stripe-billing.md): Stripe Billing handles subscriptions, invoices, payments, and usage billing. Autumn complements Stripe when your app needs credits, entitlements, limits, and pricing changes enforced in product. ## Blog - [How to build a credit ledger that scales](https://useautumn.com/blog/ai-billing-infrastructure.md): Metering token usage needs a different type of infrastructure. This article is about how to build a counter and ledger that works at high throughput and concurrency. - [Building an API for agents](https://useautumn.com/blog/building-an-api-for-agents.md): Some patterns we've found ourselves adopting as we design Autumn's API increasingly for agents instead of humans. - [How to build a flexible billing system](https://useautumn.com/blog/stop-rebuilding-billing.md): How to architect a flexible billing system that handles pricing changes well - [Saying goodbye to multi-region (for now)](https://useautumn.com/blog/active-active-redis-cache.md): Why we moved Autumn to a multi-region architecture, the tradeoffs we hit with active-active Redis, and why we eventually returned to a simpler single-region setup. - [We built a billing company but didn't replace Stripe Billing](https://useautumn.com/blog/we-built-a-billing-company-but-didnt-replace-stripe-billing.md): Why Autumn builds around Stripe Billing instead of replacing subscriptions and invoices, and where the real complexity has moved for credit-based pricing. - [Building an AI agent to automatically investigate support tickets](https://useautumn.com/blog/building-an-ai-agent-to-investigate-support-tickets.md): How we automated customer support investigations by structuring our logs and giving Claude Code the right primitives. - [Internal agents are actually useful when you give them the right primitives](https://useautumn.com/blog/coding-agents-and-abstractions.md): - [Migrating Autumn to PlanetScale](https://useautumn.com/blog/migrating-to-planetscale.md): How we migrated our core database to PlanetScale, and why it's been a game-changer for performance, reliability, and developer experience. - [Post-mortem: Database outage caused by collation migration locking conflict](https://useautumn.com/blog/post-mortem-database-outage-caused-by-collation-migration-locking-conflict.md): Post-mortem write up of an outage that affected a number of requests between 15:00 and 16:00 UTC, 15th March 2026. - [Consumer psychology is important in AI pricing (feat. T3 chat)](https://useautumn.com/blog/working-with-t3-chat-on-a-new-way-of-pricing.md): We worked with Theo and Mark from T3 Chat to build a cool new way of pricing. We learned about the psychology behind how AI products are consumed, and what that means for how we should monetize them. - [We're making some API changes](https://useautumn.com/blog/we-re-making-some-api-changes.md): A bit of context about what will be changing in the new version of the Autumn API and SDK. - [People really don't like metered billing](https://useautumn.com/blog/usage-billing-bad.md): Replit’s 2026 pricing shift highlights three trends in AI-first products: usage-based billing creates anxiety, seats don’t map to AI value, and credits/effort-based pricing reduce transparency as agents run longer. - [React vs shadcn, and trying to be too clever](https://useautumn.com/blog/component-fail.md): Learnings about building a component library for a billing platform for AI companies - [Marketing is hard](https://useautumn.com/blog/marketing.md): A little write up on our thoughts and exploration around how to market our developer tool for billing and payments. - [Architecture to run 100 stripe cases in 1 endpoint](https://useautumn.com/blog/attach.md): Handling stripes upgrades, downgrades, schedules, one off and subscriptions all in 1 endpoint. - [What if Stripe builds this](https://useautumn.com/blog/what-if-stripe-builds-this.md): Stripe has been the go-to for billing, subscriptions and managing payment logic for 16 years. We think that'll change soon. - [Embedded UI components are easier with shadcn](https://useautumn.com/blog/shadcn.md): We decided to use a shadcn/ui registry to set up our pricing components, instead of a Reactjs library. We used this approach for pricing pages, upgrade and downgrade flows and paywalls. - [A roasting from HN makes better devtools](https://useautumn.com/blog/thanks-hn.md): - [We tried to make billing backendless](https://useautumn.com/blog/backendless.md): We wanted to make payments, billing, usage limits and tracking as easy as possible. We explored a billing integration that required no backend setup, but ultimately gave up. - [How we made our first sale as a startup](https://useautumn.com/blog/how-we-made-our-first-sale-as-a-startup.md): How we generated our first revenue as a startup, and got into Y Combinator. - [Talking about billing with 30 YC founders](https://useautumn.com/blog/talking-about-billing-with-30-yc-founders.md):