John Duffield
Voice Architect at Voyager Internet Ltd
Auckland, Auckland, New Zealand
Summary
👤
Senior🎓
Top SchoolJohn Duffield is a Voice Architect with over 11 years of hands-on experience designing and operating carrier-grade voice and network systems, backed by CCIE #6123 and deep ISP/Telco expertise. He has led voice architecture and product development at Voyager and Orcon, building solutions like the Genius Go mobile-integrated fixed-line service and real-time VOIP support platforms that blend PHP/Symfony, MySQL, ENUM, SS7 and SBC integrations. Proficient as a software developer, he contributes to open-source telecom projects such as the scalable Kazoo platform, improving backend Erlang logic for call authorization and billing. Known for detailed, practical designs around NSN HIQ8000, Acme SBCs, BroadSoft, Cisco PGW and FreeSWITCH, he combines protocol-level insight with production automation and fraud-detection tooling. Based in Auckland, he brings a rare mix of carrier operations experience and developer-level contributions that accelerate time-to-production for complex voice services.
11 years of coding experience
23 years of employment as a software developer
Friends School LisburnMEng, Electronic Systems Engineering, MEng, Electronic Systems Engineering at Aston University
Github Skills (11)
telecom10
distributed-systems10
telecommunication10
erlang10
backend10
back-end-development10
api8
apidoc8
database7
interaction7
databases7
Programming languages (2)
Github contributions (5)
2600hz/kazoo
Sep 2014 - Dec 2015
The core of an open-source, distributed, highly scalable platform designed to provide robust telecom services
Role in this project:
Back-end Developer
Back-end DeveloperContributions:7 commits, 4 PRs, 3 comments in 1 year 3 months
Contributions summary:John primarily focused on improving the backend logic of the Kazoo platform, specifically relating to call authorization and billing processes. Contributions include bug fixes, such as correcting a condition in `check_bookkeeper`, and implementing new features such as adding a node handler to support local resource authorization. The user also modified the core logic and improved the precision in functions like `should_deny` and `maybe_local_resource`. The commits demonstrate a solid understanding of the underlying Erlang code base.
telecomscalableiotdistributed
bluesandnz/kazoo-provisioner
Oct 2014 - Oct 2014
Contributions:21 commits in 1 day
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