Services

An open-source contact center with no license fees

We build your contact center from open-source software – Asterisk, FreeSWITCH, and PostgreSQL – and then run and support it ourselves. There are no licenses to buy for this software: you pay only for our engineers' time. We can also install it in your own server room when call recordings must stay inside the company. If your process needs something the system doesn't do, we build it.

Get a quote Pricing

CONTACT.WORKSetupdemo data

System stack

TelephonyAsteriskFreeSWITCH, Kamailio

DataPostgreSQLRedis for events

Calls and videoWebRTCin browser

MonitoringGrafana, Zabbixalerts

CONTACT.WORKMonitoringdemo data

Monitoring

Telephony servernormal41% load

Database servernormal35% load

Recordings disk83%filling up soon

Notificationsentto support engineer

CONTACT.WORKVideo calldemo data

Video call with customer

Participantsagent and customerin browser

Videoonfor both

TechnologyWebRTCno install

Callin progress6 minutes

$0license fees for componentsTelephony, databases, monitoring

Asteriskpowers the platform's telephonyFreeSWITCH and Kamailio for heavy loads

LinuxRocky Linux on serversOr another distribution if you prefer

Cloudor your own server roomSame set of components either way

Stack

What we use

Each part of the contact center runs on a dedicated product.

AsteriskThe core of the telephony: puts calls in the queue, runs the IVR (phone menu), and records calls.

FreeSWITCHWe place it in front of Asterisk when call volume is high, for example during large outbound campaigns.

KamailioDistributes SIP traffic across phone servers when call volume is high and you run several PBXs.

PostgreSQLStores customer records, inquiry history, system settings, and reporting data.

RedisPasses events between parts of the platform quickly, so an agent sees a new call right away.

Grafana and ZabbixTrack server load and call quality, and alert engineers when something fails.

WebRTCVoice and video calls run in the browser – no separate app to install.

Language modelsOpen-source models for AI agents run on your own GPU, with no per-minute fees.

Examples

What open-source software solves

How it works in practice.

Recordings stay inside your network

Your security team won't allow call recordings to be stored outside the company. We install the PBX, database, and monitoring on-site, and AI agents run on an open-source model on your GPU. Your data stays inside your network.

Your servers
Recordings in-house
Model on your side

CONTACT.WORKDatademo data

All in-house

Call recordingsin your server roomnever leave

PBX and databaseAsterisk, PostgreSQLyour servers

MonitoringZabbixyour server

AI agentsopen modelyour GPU

Task 1 of 4

Thousands of calls a day without overload

The company needs to call thousands of customers a day. FreeSWITCH, placed in front of Asterisk, takes the main load, and monitoring shows line usage and warns you before the system overloads.

FreeSWITCH up front
Line usage
Alerts

CONTACT.WORKLoaddemo data

Mass dialing

Calls today8 400no overload

FreeSWITCHat entry pointmain flow

Line load72%normal

Notificationat 90%to engineers

Task 2 of 4

The customer shows the problem on video

It's easier for a customer to show a problem than to describe it. A WebRTC video call opens in the browser on both sides: the agent sees what's wrong right away, and more issues get resolved in a single call.

In the browser
No software
Voice and video

CONTACT.WORKVideodemo data

WebRTC video call

Customerin browserno install

Agentin browserno install

Connectivityvoice and videoover WebRTC

Summaryissue resolvedin one call

Task 3 of 4

Custom queue logic, no waiting

Calls from VIP customers need to skip the general queue and go straight to their account manager. Asterisk is open source, so we change the call flow ourselves, and VIP customers no longer wait in the general queue.

Custom call flow
No waiting
Support plan hours

CONTACT.WORKLogicdemo data

Custom flow

VIP customer callbypass main queuenew rule

Route toaccount managerfrom record

Queue waitnonefor VIP customers

Customizationonin your system

Task 4 of 4

We choose the components and servers based on your tasks and call volume, and list them in our proposal.

Results

What your company gets

Costs

License costs don't grow as you grow

The software stays free whether you have five agents or five hundred. A new seat or feature needs no license: as you grow you may need more servers and engineering hours, but you won't pay software vendors.

$0 for components
No per-seat fees
Hours for custom work

CONTACT.WORKCostsdemo data

Project costs

Component licenses$0not needed

New workstation$0no license

Engineering workin hoursfrom plan

New featureno licenseyou pay only for work

Control

No dependence on someone else's cloud

You can run the entire system yourself and connect its monitoring to your IT team's tools. Your contact center doesn't depend on whether someone else's cloud service is up today.

Your servers
Your monitoring
Your hosting

CONTACT.WORKControldemo data

What runs where

Platformyour serversin server room

Call recordingson your serversnot someone else's cloud

Monitoringyour IT teamconnected

Architectureopenfor audit

Reliability

Proven software

This software has been widely used in telephony and IT for years. We install versions we've already tested in our own test environment, and we patch known vulnerabilities right away.

Years in production
Large communities
Tested versions

CONTACT.WORKReliabilitydemo data

Component versions

Asterisktested by usbefore install

PostgreSQLtested by usbefore install

Security patchinstalledright away

New versionon test serveron hold for now

No licensesThe phone system, database, and monitoring are free software. You pay only for the work: installation, setup for your needs, and ongoing support.

Familiar to your IT teamMany engineers know Asterisk, PostgreSQL, and Zabbix. Your team can see how the system works and audit it against your own policies.

Recordings stay with youWe can install the system in your server room. Call recordings and customer data then stay in-house, as your security team requires.

Custom features from our teamWe know this software well and add the features your process is missing ourselves. No waiting for a vendor's next release.

Process

How we work

01RequirementsWe learn your call volume, channels, and security requirements.
02DesignWe choose the components, number of servers, and hosting option.
03InstallationWe deploy the components in our US and UK data centers or at your site.
04TestingBefore launch, we test calls, recording, and performance under load.
05MonitoringWe turn on server and call-quality monitoring with failure alerts.
06UpdatesWe install new versions on a schedule agreed with you.

Terms

Components: Asterisk, FreeSWITCH, Kamailio, PostgreSQL, Redis, WebRTC, and more
Servers: Rocky Linux 9; another OS on request
Deployment: CONTACT.WORK cloud, on-premises, or hybrid deployment
Licenses: Not required
Pricing: Support plan hours, plus hosting in the cloud

Planning

What to decide before installation

Where will it run?In the cloud, on your servers, or split between the two – this determines the scope of work and the number of servers.

How many calls at peak?Peak volume tells us whether you need FreeSWITCH in front of Asterisk and how many phone servers.

Do you need video?If so, we'll turn on WebRTC video and check that your network has enough bandwidth for it.

Do you need an on-site model?Then one of your servers will need a GPU for the open-source language model.

Who looks after the servers?Decide who maintains the servers: your team, our engineers, or both together.

Q&A

Frequently asked questions

Is the platform itself open source?

No. CONTACT.WORK is our own software, and its code is closed. The components are open source – the PBX, data storage, event bus, and monitoring. There are no licenses for the platform, and you don't pay the makers of these components either.

How is the platform different from a free Asterisk PBX?

A PBX handles only calls. The platform adds messaging and email, a customer record, reports, and AI agents – every customer interaction appears in a single customer timeline.

How much do Asterisk and PostgreSQL cost?

The software itself is free – it's open source. You pay only for our installation, setup, and support work, billed in support plan hours.

Why not install Asterisk ourselves?

You can, but you'll need your own Linux, telephony, and database specialists: the system has to be configured, secured, updated, and fixed when it fails. Without them, what you save on licenses goes to downtime. With us, our engineers handle all of this.

Who helps when something breaks if the software is open source?

Our engineers, under your support plan, within the response time set in your contract. No hunting for answers on community forums.

What operating system do the servers need?

Usually Rocky Linux. If your admins prefer another system, we'll install that.

Can we talk to customers on video?

WebRTC carries both voice and video, so video calls run right in the browser, with no separate software.

We already have Asterisk – can we use it?

The platform runs on top of Asterisk, so we connect your PBX along with your numbers and lines, without rebuilding anything.

Do you integrate with open-source CRMs?

We integrate with Odoo, SuiteCRM, and vTiger: call and message history appears in the customer's record in these systems.

Odoo →SuiteCRM →vTiger →

Can we order open-source software setup separately from the platform?

We set up and support Asterisk, FreeSWITCH, Zabbix, and the other software on this list, even without the CONTACT.WORK platform.

What happens if a component's maker leaves the market?

The system keeps working: open-source software is released under free licenses that can't be revoked or switched off. A community of developers keeps building it.

Is open-source software secure?

Open code alone doesn't make a system more secure – timely updates and proper configuration do. When we install the system on your servers, we protect SIP from password guessing and toll fraud: we restrict access, set up a firewall, and encrypt traffic.

How do you update components?

We track new releases, test each new version on a test server first, and only then install it for you, at an agreed time. Security fixes go in right away, without waiting for a scheduled update.

What tools do you use for development?

We keep code and change history in GitLab and track tasks and deadlines in OpenProject. Both are open source and run on our own servers.

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Glossary

Terms on this page

Cloud deployment (cloud): The platform runs on the vendor's servers, and agents connect over the internet. Learn more →
IP PBX: A company phone system that runs over the internet and your local network. Learn more →
WebRTC: Calls right from the browser, with nothing to install. Learn more →
Call recording: Calls are saved so they can be replayed and disputes settled. Learn more →
Hosting: You rent a server from a provider instead of buying one. Learn more →
IVR (interactive voice response): A phone menu: the caller hears a greeting and picks the right department. Learn more →
SIP (Session Initiation Protocol): The protocol that sets up calls in IP telephony. Learn more →
Customer record: The screen of customer data an agent sees during a conversation. Learn more →
Large language model (LLM): A neural network that understands questions asked in everyday words and answers the same way. Learn more →
On-premises deployment: The system runs on the company's own servers, not in the vendor's cloud. Learn more →
Data center: A building with servers, backup power, cooling, and network links. Learn more →
Hybrid deployment: Part of the system runs on the company's servers, part in the vendor's cloud. Learn more →
CRM – customer relationship management: Where a company keeps its customers, deals, and full communication history. Learn more →

Blog

Fresh from the blog

All articles →

Services · 7 min read Custom development of your contact center platform for your processes When contact center settings are not enough: integrations, modules, AI workflows. How to tell development from configuration and estimate the payback. Read the article → Management · 9 min read How many agents does your contact center need? Erlang C in plain English Calculate contact center staffing with Erlang C: workload, service level, shrinkage, and headcount by shift – all in one worked example. Read the article → Integrations · 7 min read CRM and phone system integration: what it does and how it works How to connect your phone system to your CRM: calls and recordings in the record, screen pop, click-to-call. What to decide first and how to check it works. Read the article →

Updated: November 10, 2026