Senior MacOS Networking Engineer

Role - Outside IR35, candidates must have their own Ltd Company, this role is fully remote working.

Job Title: Senior macOS Networking Engineer

My client is seeking an experienced macOS developer with deep expertise in the networking stack. The role involves designing and implementing a system-level networking module capable of intercepting, analysing, and transforming data flows. The engineer will be responsible for evaluating the best technical approach available within macOS frameworks and delivering a production-ready solution.

Responsibilities

• Evaluate and recommend the most suitable macOS networking framework or extension type to achieve project goals.

• Design and implement a robust module for Real Time interception and transformation of traffic flows.

• Ensure performance, reliability, and compatibility across current macOS versions.

• Collaborate with architects to integrate with external control systems.

• Provide debugging, observability, and documentation to support validation and handover.

• Participate in design reviews and contribute to long-term architectural decisions.

Required Skills

• Expert-level understanding of macOS networking stack and system-level development.

• Strong experience in Swift and/or Objective-C for system programming.

• Proven track record in developing production macOS networking software.

• Ability to debug low-level networking behavior using tcpdump, Wireshark, and other diagnostic tools.

• Strong grasp of concurrency, memory management, and optimization on macOS.

Preferred Skills

• Prior experience with VPN, Proxy, or secure networking applications.

• Familiarity with Kernel extensions, system extensions, or advanced networking APIs.

• Experience with high-throughput or performance-sensitive systems.

Other Information

. Engagement type: Contract or Permanent.
. Remote work, with preference for candidates experienced in distributed teams.
. Candidates must be eligible to work in the required jurisdictions

Please apply if you feel you have the right experience and interested in this position

GCS is acting as an Employment Business in relation to this vacancy.