Backend / Reverse-Engineering Specialist: Build "Unofficial" Production REST APIs for Closed Systems

We are looking for a backend engineer to build reliable, production-grade, "unofficial" REST APIs for a platform that lacks a public developer API. We are not looking for brittle, UI-based browser automation (like headless scrapers). Instead, we need this built at the network and protocol layer through “unofficial” APIs. Core Responsibilities - Protocol Extraction: Intercept and reverse-engineer the target system’s internal web or mobile application network traffic to map its underlying data models, endpoint paths, and state dependency graphs. - Session & Auth Management: Build a programmatic handshake to handle continuous authentication, such as MFA retrieval. - API Synthesis: Abstract the raw responses into structured, cleanly typed, modern endpoints. - Resilient Error Architecture: Implement schema verification and structured, machine-readable error catching to cleanly handle upstream application modifications without crashing the service connection. Required Tech Stack & Skills - High proficiency in backend languages optimized for networking and proxies - Advanced experience with reverse engineering - Deep understanding of web application security - Experience building strongly typed, well-documented REST APIs - Bonus: Familiarity with Model Context Protocol (MCP) or constructing APIs purpose-built for AI Agent tool-calling.