Erik Reppel, the former Coinbase Developer Platform engineering head behind x402, a payments protocol for AI agents and apps, has left the crypto exchange to start a new company.
Reppel announced the move in a post on X, May 29, saying he had "left Coinbase" and was "starting a company," though he didn't specify what the new company will do.
Reppel added he will continue working with x402 as a member of the protocol foundation's Technical Steering Committee and will also advise Coinbase on agentic commerce.
- He also said Yuga Cohler, Coinbase Developer Platform's engineering lead and a former Google engineer, will take over as head of engineering at Coinbase Developer Platform.
Launched in May 2025, x402 is a Coinbase-created payments protocol meant to let software pay for things online automatically.
Instead of a person signing up for an account or entering card details, an app, API or AI agent can receive a "payment required" message, pay in stablecoins and keep going.
Coinbase said it launched the new product in collaboration with AWS, Anthropic, Circle and NEAR.
A May 2026 academic paper, "Five Attacks on x402 Agentic Payment Protocol," said x402 introduces a cross-layer attack surface between web payments and blockchain settlement, and identified weaknesses that could lead to unpaid service or paid-but-denied outcomes.
- Earlier this year, the protocol moved beyond Coinbase. In April, the Linux Foundation, the non-profit group that hosts open-source projects, said that it was launching the x402 Foundation after Coinbase contributed the protocol, making it the neutral home for the open-source payments standard.