SDET - API/Middleware (India)

Welo Data, part of Welocalize, is a global AI data services company with over 500,000 contributors across 100+ countries. The organization focuses on delivering high-quality training data for advanced AI systems while emphasizing ethical practices and human contribution. Welo Data operates a flexible, distributed workforce model that supports both short-term project work and permanent career growth.

For the Welo Data team, we're looking for an SDET to take on deep technical testing of middleware and API layers. This is a contractor role based in India, running for 5 weeks at 35 hours per week, starting October 19th. Pay is $9.50 per hour, with potential for full-time conversion based on performance.

Your main focus will be analyzing network interactions generated by the onboarding UI. You'll work with gRPC-Web, Proto3, HTTP/2, and JSON-RPC/REST protocols to map request and response structures, schemas, headers, identifiers, and client-injected parameters. Rather than traditional UI automation, this role centers on API and network analysis, evidence generation, and creating sanitized network traces for backend validation.

Day-to-day, you'll

• Design and maintain automated API test suites covering gRPC-Web, Proto3, HTTP/2, and JSON-RPC/REST services
• Export clean HAR files and network evidence while tracing UI actions back to corresponding network requests
• Use proxy tools like Mitmproxy, Charles Proxy, and browser DevTools to intercept and validate traffic between client and server
• Develop API automation scripts in Python, Postman, and cURL for functional and regression testing
• Analyze protocol-level request/response behavior to spot defects in serialization, encoding, and transport
• Inspect payload structures including auth tokens, routing identifiers, and hidden parameters, testing both valid and malformed conditions
• Collaborate with backend and middleware engineers to define test contracts and edge cases
• Document technical findings, test coverage, and protocol-level constraints

You'll bring

• 3 to 5+ years hands-on experience with gRPC-Web, Proto3, HTTP/2, and JSON-RPC/REST
• Strong proficiency with Mitmproxy, Charles Proxy, and browser DevTools for traffic inspection
• Solid Python scripting skills plus practical experience with Postman and cURL
• Proven track record designing and maintaining test suites for middleware or API-layer services
• Deep understanding of API request structure, headers, authentication, and system parameters
• Network and protocol-level debugging expertise
• Familiarity with version control, CI integration, and code review practices
• Ability to work within approved staging environments and follow data-handling requirements

Preferred experience includes analyzing browser-generated network traffic, HAR file analysis, API schema reconstruction, and controlled API replay techniques.