PBXCore · Rust Telephony Engine (RTE)
The engine behind everything we run
PBXCore is our own realtime communications platform — voice, every messaging channel, and live AI agents in a single engine, written in Rust for the low-latency, always-on reliability communication demands. It powers our phone system, our apps, and our AI.
Why we built our own
Most providers resell someone else’s softswitch. We don’t. PBXCore is ours end to end — which is why we can fix things at the root and build features nobody else offers.
Built in Rust for realtime
A single, memory-safe binary handles signaling and media with the low, predictable latency live audio needs — no garbage-collection pauses, no mystery memory leaks taking down your calls at 2am.
Multi-tenant from the ground up
Every tenant is isolated at the core — trunks, numbers, extensions, routing, and recordings kept strictly separate. Not a single-tenant box with partitions bolted on afterward.
Scales by configuration
Runs as one node for a small deployment or splits its roles — signaling, media, conferencing, AI — across many as you grow. Same engine, same config, no re-platforming.
Encrypted by design
Turn on secure media and every call to and from a phone is TLS-signaled and SRTP-encrypted to the platform edge, with ICE for clean NAT traversal and hardening that rejects any packet that isn’t authenticated — so a stray device can’t hijack a call’s audio.
More than voice
One platform for every channel and every agent — the four capabilities that set PBXCore apart.
Multi-channel messaging
Voice is just one channel. PBXCore handles SMS, email, Telegram, and WhatsApp in the same engine — one place to reach people and be reached, and one place every conversation is logged, whichever channel it came in on. SMS runs on our own SMSGator framework.
Visual Call Flow
A drag-and-drop canvas where you build the conversation: a greeting, a question, a branch on what the caller says, a knowledge lookup, a web search, an SMS, a transfer. Callers can talk over the agent — it stops and listens, like a person would — and a flow can still mix natural speech with classic keypad menus. No code, and none of the rigid phone-tree menus customers hate.
AI Agents
Conversational agents that work live — on calls and on message threads. They ask, understand the answer, branch, call external tools to act, and hand off to a human when it matters. Answers are grounded in your own knowledge base (with a web-search fallback), never invented, and every call ends with an AI summary of who called, what they wanted, and what was promised. Pluggable LLM brain, your prompts, your rules.
Memory Engine
Memory is organized into domains, not one shared vector store — and that organization is the point. Public domains hold knowledge every agent can draw on; private domains keep each tenant’s and each caller’s history walled off at the core, isolated by default. Explicit rules decide what crosses: call history stays private, while directory facts like a caller’s name can be shared — so a returning caller is greeted by name without exposing what they discussed. Governance, not just similarity search.
Interactive Voice Agent
One interactive voice agent runs whole campaigns end to end — inbound and outbound — holding real conversations and pulling in a human only when it’s worth it.
Outbound campaigns
The agent runs fully automated outgoing call campaigns end to end — presenting the offer, answering questions, handling pre-sale details, and sending marketing materials by SMS or email.
A live agent is brought in only when the system detects confusion or an unresolved intent, so human time is spent on the calls that actually need it.
It also holds two-way SMS conversations — reading and responding to incoming messages, not just blasting them out.
It tells a live person from a voicemail box from a call-screening service — leaving the right message in each case, and only bridging a human when it has reached a real, live person.
Example use cases: fuel card sales, political outreach.
Inbound campaigns
A full replacement for traditional IVR menus. Callers speak naturally instead of navigating keypad trees.
The agent retrieves information, authenticates the caller, and routes them to the right team member when a human is needed.
Returning callers are greeted by name, and answers come grounded from your knowledge base — about your company, your services, whatever you’ve taught it.
Contact center, built in
Human agents, queues, and supervisors — every call recorded, transcribed, and searchable.
Call queues (ACD)
Skills-based routing, live SLA and wait-time boards, callback offers, and music on hold with position and hold-time announcements — a real contact center, not a hunt group.
Agents & supervisors
Agents sign in on any phone with live presence and hot-desking; supervisors monitor, whisper, and barge, move waiting callers between queues, and leave coaching notes — all under an editable roles matrix from admin down to agent.
Team tools
Mobile push wakes iPhone and Android softphones for calls and texts; click-to-dial rings your extension then bridges the number; reminders arrive by portal, SMS, or a call that reads them aloud; and broadcasts reach a queue or the whole team at once.
Live demo
Talk to our AI voice agent right now
Call the number below and have a real conversation with the agent — no signup, no form. Hear the latency, the turn-taking, and the understanding for yourself.
One engine, not seven vendors
Most businesses stitch together a phone system, a texting tool, an email platform, a chatbot, and a CRM — and pay the seams in lost context and finger-pointing. PBXCore puts voice, messaging, AI agents, and memory on one engine, so a conversation that starts as a call and continues over WhatsApp is still one conversation.
The rest of the toolkit
SMS, CDR & recording
Two-way messaging as both a channel and a flow step, plus a full call-detail record and a playable recording of every call.
MCP tool integration
Agents call external tools mid-conversation over the Model Context Protocol — look something up, check a system, take an action — the same way our own engineers build against it.
Provisioning & routing
Tenants, DIDs, extensions with QR/XML/JSON provisioning, and database-backed routing for calls and messages alike — the full PBX framework, built in.
📱 One app, either platform. Our softphones for Windows, macOS, iOS, iPadOS, and Android work with both the FreePBX Integration Suite and PBXCore — so you can switch or run both without changing what your team uses every day.
Build on the platform
Everything the dashboard does, your own systems can do too — over a clean API and a native MCP server, with access control on every key.
REST API
A tenant-scoped REST API with fine-grained access control — issue keys that read or write exactly the resources you choose, from extensions to call records with transcripts and recordings.
MCP server
The platform is itself an MCP server: connect an AI assistant — Claude, Cursor, or your own — and it can look up registrations, schedule callbacks, send SMS, and read call history, governed by that same per-key access control.
Agent access tokens
Mint short-lived tokens that act as a single agent, so you can embed the agent portal or agent APIs straight into your own software — without handing over the whole account.
It powers everything else
PBXCore is the foundation under our phone system, our softphone apps, and our conversational AI and call analytics. One engine we own, understand completely, and keep making better.