Senior Full-Stack Engineer – Python

Senior Full-Stack Engineer – Python, Identity, UCP & Wallets
Location: Remote, with at least five hours of daily overlap with US Central and UK working hours
Duration: Initial six months; extension likely

Experience: 5+ years relevant

Role Overview
Join Experian’s existing Agent Trust scrum team to build verified loyalty identity integrations across Universal Commerce Protocol (UCP) and protocol-agnostic services, along with a wallet-held Verifiable Credential proof of concept.
This is a Python-primary full-stack role. Python supports UCP and Anthropic integrations, while TypeScript/Node.js supports edge verification, wallet credentials, merchant middleware, and assistant-platform integrations. Strong working proficiency in both is required.

First 90 Days — Key Focus Areas
These are initial priorities, not a fixed backlog. Focus areas may evolve as new agentic commerce capabilities emerge.
• UCP integration — Python: Implement the com.experian.agent_trust signal with loyalty information. Build a mock merchant that verifies the signal, resolves eligibility server-to-server, applies member pricing and inventory holds, and records pending loyalty earnings. Use OAuth with PKCE identity linking for redemption and transfer.
• Edge verification — TypeScript: Define the X-Agent-Trust header contract and build a cloud-agnostic edge/serverless verifier with JWKS caching and spoofed-header removal. Develop merchant middleware that exposes verified loyalty context.
• Wallet credentials — TypeScript: Build credential issuance through OID4VCI, wallet presentation through OID4VP, selective disclosure using SD-JWT, and merchant verification. Demonstrate that no personally identifiable information reaches the agent. Explore BBS+ predicates as a stretch goal.
• Fraud testing: Test cross-merchant replay, token reuse, enumeration, account-takeover redemption patterns, and inventory hold-and-abandon abuse across both integration paths.
• Documentation and demonstrations: Write merchant integration guides for UCP and the header/middleware approach, and build demonstration storefront scenarios.
• Merchant-platform integration — TypeScript/Node.js: Add Agent Trust verification to a platform such as Shopify using relevant APIs, checkout extensions, or Functions, with minimal merchant changes.
• Bot-management and CDN integration — TypeScript: Build signed “good agent” signals, edge verification, and vendor rule examples that allow verified agents while challenging unverified automation.
• Assistant-platform integration — TypeScript: Package capabilities for commerce and assistant platforms, including potential ChatGPT Apps SDK and Microsoft Copilot integrations with Entra ID OAuth.
• Payment-wallet prototype — TypeScript: Explore how a trust credential can accompany a payment instrument in third-party web wallets and document native-wallet constraints.

Required Qualifications
• Five or more years of full-stack engineering experience, with Python as the primary backend language for production SaaS microservices.
• Solid TypeScript and Node.js proficiency, including Node.js 22, for edge, wallet, and client-facing integrations.
• Strong HTTP fundamentals.
• API security experience with OAuth 2.0 Authorization Code with PKCE, client credentials, OIDC, JWT/JWS issuance and verification, and JWKS rotation.
• Experience implementing replay controls using audience validation, token identifiers, and expiry limits.
• Microservices experience covering service-to-service authentication, header verification, injection prevention, and rate limiting.
• Ability to read protocol specifications precisely and deliver independently from written acceptance criteria.

Preferred Qualifications
• Experience shipping third-party commerce or assistant-platform integrations, including OAuth installation and platform review processes.
• Experience building authenticated MCP servers in TypeScript.
• Hands-on knowledge of W3C Verifiable Credentials 2.0, OID4VCI/OID4VP, and SD-JWT VC.
• Familiarity with DID methods such as did and did, and at least one wallet SDK.
• Exposure to BBS+ or zero-knowledge predicate tooling.
• Edge/serverless experience with AWS CloudFront Functions, Lambda@Edge, or equivalent platforms, including state-storage integrations.
• Familiarity with UCP, RFC 9421, RFC 8693, and OpenID specifications.
• Experience with Google UCP or Merchant Center, loyalty/promotions systems, e-commerce fraud, or bot management.
Key Deliverables
UCP signal schema and platform-agent reference implementation; mock merchant with loyalty tiers; signed-header contract, edge verifier, and middleware SDK; credential issuer/wallet/verifier proof of concept; fraud test suite; integration guides; and demonstration scenarios.

Interview Process
One 45-minute live technical interview: 15 minutes of discussion followed by 30 minutes of Python and TypeScript/Node.js problem solving on your own machine. AI tools are allowed on screen. Finalists meet the product owner and security lead.
Occasional travel to partner or merchant sites may be required.