We open-sourced Tanso, a monetization engine for AI
We open-sourced Tanso Core: a self-hosted monetization engine for B2B AI products. Usage metering, prepaid credits, entitlements, and Stripe billing in one Spring Boot service, with one property the rest of the stack doesn't have. Every metered event carries its cost. Repo: https://github.com/tansohq/tanso-oss The gap If you sell an AI product today, your monetization stack is split across two categories of tools that don't talk to each other. Billing platforms meter usage and generate invoices, but they have no idea what your inference costs. They can tell you a customer consumed 40,000 events. They cannot tell you whether you made money on them. LLM observability tools know your costs down to the token, but they don't bill anyone. They can tell you a feature costs $0.038 per run. They cannot connect that to what the customer paid for it. So margin per customer, the number that decides whether your pricing works, lives in neither system. Most teams reconstruct it in a spreadsheet, quarterly, if at all. Tanso keeps both sides in one ledger. Every event you ingest records what you billed and what it cost you: input and output tokens, model, provider. Margin per customer, per feature, per model is a query, not a project. What it allows Enforcement at ingestion, not at invoice time. Entitlement checks, usage caps, and credit limits are applied when the event comes in. If a customer is out of credits, the check fails now, not on a reconciliation job three weeks later. For AI products, where a runaway integration can burn real money in an afternoon, this is the difference between a limit and a suggestion. Credits as a first-class primitive. Prepaid credit pools per customer, with grants, deductions, expirations, and full transaction history. Most AI products end up selling some form of prepaid usage. Bolting that onto a subscription-shaped billing system is painful; here it's the core model. Stripe as a payment adapter, not the source of truth. Billing state lives in Tan