Payment infrastructure provider Tempo activated its mainnet on Wednesday, introducing a Layer 1 blockchain it says is designed specifically for high-volume payment workloads, along with an open protocol for machine-to-machine transactions co-developed with Stripe.

The launch includes a payments directory with more than 100 integrated service providers spanning model providers, developer infrastructure, and data services, according to a statement.

Tempo, initially announced in September by Stripe and Paradigm, raised $500 million in a Series A funding round in October at a $5 billion valuation, with participation from Thrive Capital, Greenoaks, Sequoia Capital, Ribbit Capital, and SV Angel, according to previous reports. Stripe and Paradigm, which incubated the project, did not participate in the round.

The project launched a public testnet in December. Since then, the Tempo team said it has been working with design partners across payments, commerce, and financial services to bring "real payment workloads onto stablecoins."

Those partners include Anthropic, DoorDash, Mastercard, Nubank, OpenAI, Ramp, Revolut, Shopify, Standard Chartered, and Visa, among others. The collaborations span global payouts, cross-border remittances, embedded finance, and tokenized deposits, according to the statement.

Machine Payments Protocol

Alongside mainnet, Tempo introduced the Machine Payments Protocol, an open standard for machine payments co-authored with Stripe. MPP provides a standardized method for agents and services to coordinate payments programmatically, defining a protocol for requesting, authorizing, and settling payments between machines, according to the statement.

The protocol was launched in open source to ensure machine payments function consistently across different services and payment rails, the Tempo team said.

While MPP runs on Tempo's blockchain, the protocol is designed to be rail-agnostic and extensible. Visa has extended MPP to support card-based payments on its network, Stripe has extended it to cards, wallets, and other payment methods through its platform, and Lightspark has extended it to bitcoin payments over the Lightning network, per the statement.

The Tempo team said MPP supports a feature called "sessions" that enables continuous payments for autonomous agent activity. When an agent opens a session, funds are set aside upfront, allowing payments to stream continuously as the agent consumes resources from services without requiring a separate onchain transaction for each interaction. Thousands of small transactions can be aggregated into a single settlement transaction, according to the team.

The payments directory launched alongside mainnet provides a unified catalog of MPP-compatible services that agents can transact with automatically. At launch, the directory includes integrations with more than 100 services, including Alchemy, Dune Analytics, Merit Systems, and Parallel Web Systems, spanning model providers, developer infrastructure, compute platforms, and data services, the statement said.