Senior Software Engineer (Payment Protocols & Security)

Description

**Senior Software Engineer (Payment Protocols \& Security)** **Contractor / PJ** We are looking for a **Senior Software Engineer (Payment Protocols \& Security)** to drive people and businesses forward through innovation, with attitude, initiative, and a focus on execution. **Your impact in this role:** * Agent Protocol Implementation: Develop integrations and translate specifications (specs) of Verifiable Intent, Visa Intelligent Commerce, Google AP2, and OpenAI ACP protocols into code. * Cryptographic Engineering: Implement cryptographic signatures and develop flows for Intent Mandate (formal purchase request) and Payment Mandate—core components of the Verifiable Intent protocol. * Zero Data Exposure (PCI-DSS Compliance): Architecturally ensure credit card data (Zero PAN in chat) is never exposed to AI agents or stored in logs, integrating flows with Getnet’s Wallet for tokenization. * Handshake and Identity (A2A): Implement the Google AP2 protocol handshake using Verifiable Credentials to attest secure, mutual identification between agents. * Messaging Interoperability: Integrate the OpenAI ACP protocol to standardize purchase intent messages and checkout flows between the orchestrator and external agents. * ✅ **Essential Requirements:** * Programming Languages: Advanced proficiency in MCP server-side languages (Python, TypeScript, or Node.js). * Security and Cryptography: Practical expertise in public key infrastructure, delegation-of-authority standards (e.g., Verifiable Credentials and SD-JWT delegation chains), and transactional security standards such as PCI-DSS. * Communication Protocols: Strong experience with REST APIs and event-driven asynchronous communication logic (critical for protocols like ACP). * Tokenization and Payments: Hands-on experience integrating transactional flows, payment gateways, and card tokenization (Wallets). * **Desirable:** * Familiarity with Identity and Access Management (IAM) platforms such as ForgeRock, used in the base architecture. * Knowledge of preview specifications in the card ecosystem (e.g., Visa Intelligent Commerce) and consent/data rights management flows for agents. * Prior experience developing or architecting the Model Context Protocol (MCP). * **Benefits:** Remote work allowance Flash card Access to South Academy courses and certifications Financial education program **About South:** You’ll join a collaborative team with autonomy and a commitment to continuous improvement, working on projects that deliver real business impact—where turning ideas into delivery is part of everyday life. We’re recognized for our people: We’ve been named one of Brazil’s best places to work twice (GPTW). We’re committed to the future: We are a carbon-neutral company. Interested? Apply now and help us make it happen.