About Us
We are building Yottavox® - a modern cloud-hosted PBX platform designed for clarity, performance, and scalability. The product is currently in development and we are now hiring a talented Full-Stack PBX/VoIP Developer to join at an early stage and take a key role in the build.
This is a unique opportunity to work on a new platform from the ground up, without legacy constraints, and help shape a clean, modern telephony system built for real-world operators and end-users.
The Role
You will be responsible for developing the core PBX functionality, APIs, and admin interface. Working closely with design and product, you’ll build a reliable, secure, multi-tenant VoIP platform with a strong focus on quality and long-term maintainability.
Key Responsibilities
1. Core PBX & VoIP Development
* Build call routing, extension logic, IVR, queues, voicemail, and CDR workflows.
* Develop predictable, efficient, secure VoIP behaviour with multi-tenant capability.
2. Backend Architecture & APIs
* Design and implement scalable backend services and REST APIs for provisioning, configuration, and reporting.
* Follow clean architectural patterns and maintain high coding standards.
3. Frontend Implementation
* Develop a modern admin interface using React/Vue (or similar).
* Work from wireframes and collaborate with design to deliver a clean, intuitive experience.
4. Integrations & Infrastructure
* Integrate with SIP trunk providers, manage number routing and failover logic.
* Build tooling for diagnostics, monitoring, real-time events, and system health.
5. Quality, Security & Stability
* Ensure telecom-grade reliability with proper SIP/RTP handling, NAT traversal, SRTP/TLS, fraud controls, and error management.
* Optimise for low latency, resilience, and predictable performance under load.
6. Documentation & Technical Clarity
* Maintain clear documentation for APIs, data models, call flows, and system components.
* Ensure all work is structured, readable, and easy to maintain or extend.
7. Collaboration & Delivery
* Work closely with design, product, and a fractional architect.
* Communicate clearly, follow consistent patterns, and deliver high-quality implementations without micro-management.
8. Environment Setup & Testing
* Support containerised dev environments, basic CI/CD, and automated tests for critical flows.
* Prepare for staging and early-access deployment.
Required Experience:
* Strong VoIP engineering background and experience building PBX or SIP-based systems.
* Deep knowledge of SIP, RTP, media handling, and related telecom protocols.
* Hands-on experience with Asterisk and ideally FreeSWITCH..
* Solid backend development skills in Node.js, Go, Python, or C++.
* Strong understanding of REST APIs, authentication, and database design.
* Experience with React, Vue, or similar front-end technologies.
* Familiar with Docker, cloud hosting environments, and modern DevOps practices.
* Good understanding of VoIP security (TLS/SRTP, NAT traversal, rate limiting).
Nice to Have:
* Experience with multi-tenant SaaS architecture.
* Knowledge of SIP trunking, number routing, failover logic.
* Familiarity with call recording, CDRs, and telecom observability tools.
* Experience integrating with SBCs or media servers.
What We Offer:
* Competitive salary based on experience.
* Remote working
* A chance to build a new platform from scratch - no legacy code.
* Early technical influence with significant autonomy.
* Opportunity to grow into a senior or lead role as the platform scales.
Job Type: Fixed term contract
Contract length: 12 months (with strong potential for permanent on review)
Benefits:
* Casual dress
* Work from home
Work Location: Remote