Job Overview Welo Global is hiring an SDET (Software
Development Engineer in Test) to bring deep technical rigor to
middleware-layer testing. This role requires strong technical
expertise across gRPC-Web, Proto3, HTTP/2, JSON-RPC/REST,
proxy-based traffic inspection, and API scripting. The primary
responsibility is to observe and reconstruct the network
interactions generated by the onboarding UI, including
request/response structures, schemas, headers, identifiers, Enums,
and client-injected parameters. This is primarily an API/network
analysis and evidence-generation role rather than a conventional UI
automation or regression-testing role. The resource will produce
sanitized network evidence and controlled, benign tracer replay
scripts for downstream backend validation. Project Details Title:
SDET - API/Middleware Rate: $9.50/hr Start Date: 19th October
Duration: 5 Weeks Commitment : 35 Hours per Week Location: India
(Remote) Job Type: Freelance Responsibilities Design, build, and
maintain automated API test suites covering gRPC-Web, Proto3,
HTTP/2, and JSON-RPC/REST based services Export clean, sanitized
HAR/network evidence while maintaining traceability between UI
actions and corresponding network requests. Map relevant schemas,
headers, identifiers, routing information, and client-injected
parameters. Use proxy tools such as Mitmproxy, Charles Proxy, and
browser DevTools to inspect, intercept, and validate network
traffic between client and server Develop and maintain API
automation scripts using Python, Postman, and cURL for functional
and regression testing Analyze protocol-level request/response
behavior to identify defects related to serialization,



encoding,
and transport Inspect and validate request payload structure,
including system-level headers (e.g., auth tokens, routing
identifiers) and internal/hidden parameters, ensuring correct
handling under both valid and malformed conditions Collaborate with
backend and middleware engineers to define testable contracts and
edge-case scenarios Continuously improve test automation frameworks
for reliability, speed, and maintainability Document technical
findings, automation coverage, and known protocol-level limitations
Required Qualifications Solid hands-on expertise of 3-5+ years
with gRPC-Web, Proto3, HTTP/2, and JSON-RPC/REST protocols
Proficiency with proxy/traffic inspection tools including
Mitmproxy, Charles Proxy, and browser DevTools Solid
scripting/programming skills in Python, with practical use of
Postman and cURL for API automation Experience designing and
maintaining automated test suites for middleware or API-layer
services Working understanding of API request structure, including
headers, auth tokens, and internal/system parameters, and how to
test for their correct handling Understanding of software
engineering practices as applied to test automation (version
control, CI integration, code review) Strong debugging skills at
the network/protocol level Experience analysing browser-generated
network traffic and reconstructing API behaviour is strongly
preferred. Experience with HAR analysis, API schema reconstruction,
or controlled API replay is strongly preferred. Ability to work
within approved staging/test environments and follow defined
data-handling and test-authorization requirements is
required.

📌 SDET- API/Middleware (New Delhi)
🏢 Welocalize
📍 New Delhi