*Indicative; subject to carrier, network conditions, and topology.
What we do
Zen Systems is a communications engineering partner specialising in SIP, VoIP, and telephony infrastructure for teams building communication-heavy products or integrating complex call flows into their existing systems.
We work alongside in-house engineering and product teams to design, implement, and operate SIP-powered solutions — from bespoke routing engines and IVR workflows through to deep integrations with core business platforms.
Why partners choose Zen Systems
We're not a generic voice provider. We're an engineering partner that stays close to the architecture, the constraints, and the roadmap of the products we support.
Typical collaborations include new product builds, major telephony migrations, and the introduction of event-driven SIP logic into existing platforms.
Deep SIP & telephony expertise
Interoperability, carrier relations, SBCs, codecs, NAT traversal — the unglamorous parts that make or break real-world deployments.
Custom communication logic
We design and implement call flow engines, webhook-driven routing, and application logic tailored to your domain.
Built for product teams
We work in the same rhythms as your engineering org: version control, environments, CI/CD, and observability baked in.
From design to operations
Architecture, PoC, implementation, optimisation, and long-term support — not just a hand-off of configs.
Integration & development capabilities
We help teams embed telephony where it matters — inside products, workflows, and operational systems.
Where we integrate
- Web and mobile applications
- CRM, ERP, and line-of-business systems
- Workflow and automation platforms
- Contact centres and field operations
- IoT and on-site systems that need voice awareness
What we build
- Custom SIP routing and policy logic
- IVR flows and event-driven call handling
- Webhooks and REST APIs for call control & insights
- Bridges between on-prem PBXs and cloud services
- Migration paths from legacy telephony to modern stacks
Technology surface
If your stack isn't listed here, that's often where the interesting work starts. The earlier we talk, the better the integration outcome.
Let's explore what we can build together.
Whether you're planning a new SIP-powered product, a major telephony integration, or just need to sanity-check an approach, we're happy to start with a technical conversation.
For non-developer enquiries, visit the main Zen Systems site.