The Communications Control Plane | SignalWire

The communications control plane

Compose AI agents, human agents, and real-time communications into one system you control in code. One programmable platform for everything that happens on a call. Built by the creators of FreeSWITCH.

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ARCHITECTURE

Production is a costly place to discover architectural mistakes

In staging, webhooks arrive fast and in order. Production is less polite. On SignalWire, state lives inside the call so that your code defines logic instead of managing event timing. The same architecture that works at 10 calls works at 10,000.

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Traditional CPaaS

Telephony vendor + WebRTC vendor + AI vendor

Your responsibility to rebuild state from events

Endless race conditions

Rogue AI that won’t stay on task

Bolted on AI adds latency

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Platform

One Programmable Unified Communications platform

Calls are first-class objects with state attached

The developer is in full control of call behavior

AI Agents follow code logic and stay on task

AI Kernel directly in the media stack for lowest latency

THE CODE

One engine. Fully programmable.

The platform handles state, timing, coordination, and infrastructure. You build AI agents and call flows, so your code spends its time on your product instead of the plumbing.

IVR and Call Routing

AI Voice Agents

Contact Center

01 Route by AI Voice

Get the DTMF out of here. The caller says what they need and the flow routes on it.

02 Route by Who’s Calling

Look the caller up and route on account, tier, or history. The lookup and the decision live in one flow, no orchestration layer between them.

03 Answering Machine Detection

Tell human, machine, and fax apart on outbound calls and branch on the result. It's a native verb, not a service you integrate and reconcile.

Route by AI Voice

copy

copied!

01 02 03 04 05 06 07 08 09 10 11 12

version: 1.0.0

sections:

main:

- prompt:

play: ["say: In a few words, what are you calling about?"]

# Speech in, not digits. What they say becomes the route.

speech_language: en-US

speech_hints: ["sales", "support", "billing"]

- switch:

variable: prompt_value

case:

sales:

- connect: { to: "+15551112222" }

support:

- connect: { to: "+15553334444" }

default:

- connect: { to: "+15555556666" }

IVR and Call Routing

Explore IVR and call routing →

Built from the media engine up

The same team created FreeSWITCH, the media engine much of the industry runs on, then spent two decades building the platform around it, down to the carrier. Because we own that layer, the control plane goes all the way down. You're programming the network itself, not a wrapper over someone else's.

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CONTROL PLANE

One programmable layer runs the whole call.

Voice, video, messaging, and AI run through one control plane. The call stays on the platform for its whole life instead of bouncing between vendors. Recording, queues, transfers, agents: whatever the session needs next is one instruction away.

Explore the control plane →

SYSTEM-DIRECTED AI

You write the logic. Voice AI follows it.

Putting business logic in a prompt means hoping the model stays on script. A system-directed agent runs the conversation as a state machine of steps you define in code. At each step the model sees only the tools and data you expose. Off-script is not a state that exists.

greet

tools: none · next: collect

Instructions only.

collect

tools: check_calendar · next: confirm

Finds real openings.

confirm

tools: book_appointment · next: wrap_up

The software acts; the model only requests.

wrap_up

tools: none · next: none

Structurally complete.

The model makes it natural. Your code runs the show.

See how an agent is built →

Try it now

Sigmond Runs on SignalWire

A voice and video AI agent built on the SignalWire SDK, wired to a live knowledge base, able to see what you show him. Build the same thing on voice, phone, WhatsApp, or SIP, or an entire white-label platform with SignalWire as the network underneath.

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CUSTOMER PROOF

Join the thousands of developers

“It took us maybe a day to get a proof of concept working. ”

Mark Lilien

CTO at Textline

“I was able to develop and ship the first version within 6 hours. Within 24 hours customers were signing up.”

David Plappert

Founder at PhoneLiveStreaming

“We really appreciate the carrier-grade quality of service.”

Murray Kawchuk

Head of Strategy at Conversate

“It took us maybe a day to get a proof of concept working. ”

Mark Lilien

CTO at Textline

“I was able to develop and ship the first version within 6 hours. Within 24 hours customers were signing up.”

David Plappert

Founder at PhoneLiveStreaming

“We really appreciate the carrier-grade quality of service.”

Murray Kawchuk

Head of Strategy at Conversate

“It took us maybe a day to get a proof of concept working. ”

Mark Lilien

CTO at Textline

“I was able to develop and ship the first version within 6 hours. Within 24 hours customers were signing up.”

David Plappert

Founder at PhoneLiveStreaming

“We really appreciate the carrier-grade quality of service.”

Murray Kawchuk

Head of Strategy at Conversate

“It took us maybe a day to get a proof of concept working. ”

Mark Lilien

CTO at Textline

“I was able to develop and ship the first version within 6 hours. Within 24 hours customers were signing up.”

David Plappert

Founder at PhoneLiveStreaming

“We really appreciate the carrier-grade quality of service.”

Murray Kawchuk

Head of Strategy at Conversate

For Developers

Dive into documentation

From pip install to production. Guides, API references, and SDKs to start building complex communications flows.

Communications Platform

AI Voice Agents

SWML

Define voice, video, messaging, and AI flows in JSON or YAML. Built-in methods for every call primitive, served statically or generated per request.

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REST APIs

Every capability is a REST call: send an SMS, place a call, provision a number. Twilio-compatible, so existing code runs once you swap the credentials.

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Realtime SDKs

Control calls in real time over WebSocket with the RELAY SDKs. React to call events as they happen, in the language you already use.

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One platform for everything on the call

One platform for voice, AI, and messaging, on infrastructure that runs all the way down to the carrier. Every part of the call, programmable from one place.

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Dive into docs