Pure Rust SIP Stack

Enterprise PBX.No FreeSWITCH. No Asterisk.

A complete PBX built from scratch in Rust — SIP parser, B2BUA, RTP relay, conference mixer. 20,000 lines replacing 2 million.

20KLines
4Crates
255+Endpoints
35+RLS Tables

Everything a Modern PBX Needs

12 core modules, all managed through the Portal UI and REST API.

Extensions

CRUD, bulk import/export, provisioning profiles for SIP phones and softphones.

Ring Groups

4 hunt strategies — simultaneous, sequential, round-robin, weighted routing.

IVR Menus

Multi-level menus, DTMF routing, time-of-day conditions, failover destinations.

Call Queues

Agent management, configurable hold music, max wait time, queue callbacks.

Voicemail

Custom greetings, message management, email notifications with audio attachments.

Conferences

PIN-protected rooms, moderator controls, mute/kick, participant limits.

Call Flows

Visual drag-and-drop flow builder with conditions, branches, and sub-flows.

Routes

Inbound/outbound routing rules, time conditions, regex pattern matching, trunks.

CDR

Call detail records with advanced filters, date ranges, and CSV export.

Recordings

On-demand and automatic call recording, streaming playback, bulk download.

Music on Hold

Multiple categories, track management, per-queue and per-tenant playlists.

Active Calls

Real-time call monitoring dashboard — listen, whisper, barge, hangup, transfer.

How BitsPath Voice Compares

Side-by-side with the incumbents — on architecture, not marketing.

FeatureBitsPath VoiceFreeSWITCHAsterisk3CX
LanguageRustCCC++ (proprietary)
Codebase Size~20,000 lines2,000,000+ lines1,000,000+ linesProprietary
LicensePlatform subscriptionMPL 1.1 / CommercialGPL v2 / CommercialPer-user license
SIP Stackbitspath-sip (custom)mod_sofia (oSIP)chan_pjsip (PJSIP)Proprietary
Media Enginebitspath-media (SRTP, G.711/G.722)mod_dptoolsBuilt-inBuilt-in
Web Admin UIIncluded (Portal)FusionPBX (separate)FreePBX (separate)Included
Multi-TenantNative RLS (35+ tables)Domain-based (add-on)Not nativeLimited
REST API255+ endpointsESL + mod_xml_curlAMI / ARIProprietary API
WebRTCWebSocket transportmod_vertoBuilt-in (limited)Built-in
Memory SafetyGuaranteed (Rust)Manual (C)Manual (C)Unknown

Four Purpose-Built Crates

No forks, no wrappers, no FFI bindings. Every line is ours.

bitspath-sip~3,500

SIP parser, transactions, transports (UDP/TCP/TLS/WebSocket). RFC 3261 compliant message parsing with zero-copy headers.

bitspath-pbx~6,650

Registrar, routing engine, CDR, call forwarding, ring groups, IVR menus, voicemail, and conference bridge orchestration.

bitspath-media~3,000

RTP/RTCP/SRTP processing, G.711 and G.722 codecs, adaptive jitter buffer, conference mixing with N-1 audio streams.

bitspath-call~7,000

B2BUA call engine, call state machine, RTP relay with oRTP, NAT latching, reinvite handling, and oRTP-based oRTP relay.

Ready to replace your legacy PBX?

Deploy a modern, memory-safe PBX with a REST API, multi-tenant isolation, and a web UI — in minutes, not months.