Services

Current senior VoIP/SIP services

Zypager currently focuses on senior-level VoIP/SIP engineering: Asterisk, FreeSWITCH, Kamailio, OpenSIPS, RTPengine, SIP trunks, RTP troubleshooting, SIP security, Homer/SIP capture, ARI applications in Go and private speech-to-text workflows using Vosk. These are the services available now.

Available now

Troubleshooting

Find the failing leg and fix it.

SIP Trunk Troubleshooting

Inbound and outbound call failures, isolated to the leg that breaks.

SIP4xx/5xxPAI/RPIDcodecs

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RTP / No-Audio Troubleshooting

One-way audio and no audio, separated from signalling.

RTPSRTPNATSDP

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SIP Capture / Homer

See every call. Search by Call-ID. Escalate with evidence.

HomerHEPsiptraceRTP

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Platform Engineering

Systems that are easier to debug and safer to run.

Asterisk Consulting

Dialplan, PJSIP and ARI that are easier to debug and safer to run.

PJSIPARIqueuesIVR

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FreeSWITCH Consulting

Dialplan, profiles and ESL applications on a predictable FreeSWITCH.

FreeSWITCHESLprofilesdialplan

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Kamailio Consulting

SIP edge routing, registrar and dispatcher built to scale.

routingdispatcherTLSRTPengine

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OpenSIPS Consulting

High-availability SIP routing, trunking and carrier integration.

routingHAtrunkingNAT

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RTPengine Consulting

Media relay and SRTP/RTP bridging that actually carries audio.

RTPSRTPICEDocker

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Asterisk + Kamailio + RTPengine Deployment

A full voice stack — edge, media and application — built and documented.

AsteriskKamailioRTPenginedeployment

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Security

Close the exposure before it becomes a fraud bill.

VoIP Security Audit

Close the exposure before it becomes a fraud bill.

exposurefraudTLS/SRTPrate-limit

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Advanced Voice Applications

ARI, Go, offline ASR and carefully scoped automation.

Asterisk ARI Development in Go

Event-driven call control in Go, built to be tested and trusted.

ARIGobridgesrecording

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Go Voice Application Development

Custom voice backend services in Go, around Asterisk and SIP.

GoARIservicesPostgreSQL

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Offline Speech-to-Text with Vosk

Private offline ASR for Asterisk recordings, ARI workflows and transcription.

Voskoffline ASRAsterisktranscription

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WebRTC-related work may be reviewed separately where it is directly connected to Asterisk, Kamailio, RTPengine or SIP troubleshooting, but it is not currently offered as a standard fixed-price service.

Future / architecture direction

Future omnichannel contact-centre platform direction

Zypager is also researching and designing a future omnichannel contact-centre platform. This is not currently sold as a ready-made product, but it guides the long-term architecture and technical direction of the company. Future platform direction does not mean these features are currently available as a finished product.

Omnichannel contact-centre workflowsWhatsAppFacebook MessengerInstagram DMTikTok messaging (where provider APIs allow)SMSEmailWeb chatChatbotsAI-assisted responsesTranscriptionsCall summariesAgent workflowsCampaignsAutodiallerPreview diallerProgressive diallerPower diallerPredictive diallerCall outcomesCallbacksContact-centre automationGo backend servicesPostgreSQLRedisNATS / RabbitMQ

These future platform areas are not currently offered as standard fixed-price services. They may be discussed as architecture discovery or long-term development projects only. Custom discovery or architecture consulting may be available for selected projects, but full omnichannel platform delivery is quoted separately and only after careful scoping. Provider/API limitations apply.

Not sure which service you need?

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