Hire the Best Freeswitch Specialists

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Gaurav L.

Bhopal, India

$24/hr
4.7
215 jobs

I help businesses build reliable, scalable communication systems and web applications by combining deep expertise in VoIP (3CX & Yeastar) with full-stack development and API integrations. With 6+ years of experience in 3CX, hands-on expertise in Yeastar Cloud PBX, and 3+ years in full-stack development, I specialize in delivering end-to-end solutions — from telephony infrastructure to CRM integrations and custom dashboards. 🔥 What I Can Do For You ☎️ VoIP & PBX Solutions (3CX + Yeastar) 3CX setup, configuration & troubleshooting (V18/V20) Yeastar Cloud PBX deployment & management SIP Trunk integration (Twilio, Telnyx, Flowroute, etc.) IVR, Call Queues, Ring Groups, Call Routing Predictive / Progressive Dialer setup Call recording, reporting & analytics Multi-tenant PBX architecture DID management & call flow optimization 💻 Full Stack Development Backend: PHP, Node.js, Golang Frontend: JavaScript, HTML, CSS, Bootstrap, Tailwind Database: MySQL, PostgreSQL Build scalable CRM systems & dashboards WebRTC / SIP dialer development Real-time systems & automation workflows 🔗 API Development & Integrations (Swagger/OpenAPI) REST API design & development Swagger/OpenAPI documentation CRM integrations (Zoho, Salesforce, Monday, etc.) Webhooks, automation, and data sync systems 🌐 WordPress Development Custom theme & plugin development Website optimization & speed improvements API integrations with WordPress Business websites & landing pages 💡 Why Clients Choose Me ✔ 6+ years in VoIP & telephony systems ✔ Strong backend + infrastructure understanding ✔ Fast troubleshooting & problem-solving ✔ Clean, scalable, production-ready solutions ✔ Excellent communication & long-term support 📌 Recent Work Highlights Built multi-company 3CX dialer system with CRM integration Deployed Yeastar Cloud PBX for international clients Developed VoIP analytics dashboards & call tracking systems Integrated Twilio / Telnyx with custom applications Created API-driven automation workflows using webhooks 🎯 Let’s Work Together If you need help with: Setting up or fixing your 3CX / Yeastar PBX Building a custom dialer or VoIP system Integrating APIs or CRM systems Developing a scalable web application 👉 Send me a message — I’ll provide a clear solution quickly.

  • PHP
  • Python
  • JavaScript
  • Telecommunications
  • Full-Stack Development
  • VoIP PBX
  • Call Center Management
  • 3CX
  • System Administration
  • API Integration
  • HubSpot
  • API Development
  • API
  • Pipedrive
  • WordPress
Oleksii B.

Kiev, Ukraine

$75/hr
4.9
152 jobs

👋 Hi, I’m Oleksii - a Twilio expert with over 7 years of hands-on experience building scalable, real-time communication systems using the full Twilio stack: 📞 Programmable Voice / SMS, 🧠 TaskRouter & Flex, 🎛️ Studio, Functions, Conversations, Sync, Webhooks and more. I’ve successfully completed 120+ Twilio projects on Upwork, including: • Eliminating latency issues in phone calls 🔧 • Creating SMS marketing automation pipelines 📲 • Developing full-scale Flex dashboards with custom workflows 🧩 Clients describe me as: “Very skilled, excellent communicator, smart guy and a pleasure to deal with.” “Oleksii was very helpful and available :) We no longer have problems with latency during our phone calls.” 🛠 Whether you need help with: • Twilio Studio call flows • Complex webhook-based automation • TwiML, IVR, call forwarding setups • Integrating Twilio with CRMs or internal systems • Building voice/SMS logic in Node.js, Laravel, or Firebase environments …I’ve got you covered. Let’s bring your Twilio-powered solution to life 🚀 Feel free to invite me to your job or message me with questions.

  • Vue.js
  • Git
  • SMS Gateway
  • SMS
  • VoIP
  • Call Center Software
  • Laravel
  • Twilio
  • PHP
  • Twilio API
  • API Development
  • Telephone System
  • Chat & Messaging Software
Anil K.

Basti, India

$12/hr
4.9
181 jobs

I specialize in Twilio development, including Twilio Functions, Twilio Studio Flow, and TwiML. I have extensive experience building SMS, Voice, IVR systems, call automation, and API integrations using Twilio. With 8 years of experience in automation and API integrations, I develop custom solutions that help businesses automate communication and streamline their workflows using Twilio. Specializations: 💬 𝐓𝐰𝐢𝐥𝐢𝐨 𝐒𝐌𝐒 & 𝐌𝐌𝐒 𝐈𝐧𝐭𝐞𝐠𝐫𝐚𝐭𝐢𝐨𝐧 Sending transactional and bulk SMS/MMS using Twilio APIs with delivery tracking and automation. 💬 𝐓𝐰𝐢𝐥𝐢𝐨 𝐖𝐡𝐚𝐭𝐬𝐀𝐩𝐩 𝐁𝐮𝐬𝐢𝐧𝐞𝐬𝐬 𝐀𝐏𝐈 𝐈𝐧𝐭𝐞𝐠𝐫𝐚𝐭𝐢𝐨𝐧 WhatsApp messaging automation, template messaging, and CRM integrations using Twilio WhatsApp API. 📞 𝐓𝐰𝐢𝐥𝐢𝐨 𝐕𝐨𝐢𝐜𝐞 𝐀𝐏𝐈 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 Custom voice calling applications including inbound/outbound calls, call routing, and automation. 📲 𝐈𝐕𝐑 𝐂𝐚𝐥𝐥 𝐅𝐥𝐨𝐰 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 Advanced IVR systems with DTMF input, call routing, business hour logic, voicemail, and callback features. ☎️ 𝐓𝐰𝐢𝐥𝐢𝐨 𝐀𝐈 𝐀𝐠𝐞𝐧𝐭 & 𝐂𝐨𝐧𝐯𝐞𝐫𝐬𝐚𝐭𝐢𝐨𝐧𝐚𝐥 𝐀𝐈 𝐃𝐞𝐯𝐞𝐥𝐨𝐩𝐦𝐞𝐧𝐭 Building AI-powered voice and messaging agents using Twilio integrated with AI models to automate customer conversations, lead qualification, smart responses, and support across voice, SMS, and WhatsApp channels. ⚙️ 𝐓𝐰𝐢𝐥𝐢𝐨 𝐒𝐭𝐮𝐝𝐢𝐨 𝐖𝐨𝐫𝐤𝐟𝐥𝐨𝐰 𝐀𝐮𝐭𝐨𝐦𝐚𝐭𝐢𝐨𝐧 Designing and implementing automated communication workflows using Twilio Studio. ⚙️ 𝐓𝐰𝐢𝐥𝐢𝐨 𝐒𝐈𝐏 𝐓𝐫𝐮𝐧𝐤 𝐂𝐨𝐧𝐟𝐢𝐠𝐮𝐫𝐚𝐭𝐢𝐨𝐧 Setup and configuration of Twilio Elastic SIP Trunks for VoIP systems and PBX integrations. 𝐓𝐰𝐢𝐥𝐢𝐨 𝐒𝐈𝐏 𝐃𝐨𝐦𝐚𝐢𝐧 𝐒𝐞𝐭𝐮𝐩 Configuration of SIP domains for secure voice communication and softphone connectivity. 𝐓𝐰𝐢𝐥𝐢𝐨 𝐅𝐥𝐞𝐱 𝐂𝐨𝐧𝐭𝐚𝐜𝐭 𝐂𝐞𝐧𝐭𝐞𝐫 𝐈𝐦𝐩𝐥𝐞𝐦𝐞𝐧𝐭𝐚𝐭𝐢𝐨𝐧 Deployment and customization of Twilio Flex for cloud-based contact center solutions. 𝐂𝐨𝐧𝐟𝐞𝐫𝐞𝐧𝐜𝐞 𝐂𝐚𝐥𝐥𝐢𝐧𝐠 & 𝐂𝐚𝐥𝐥 𝐌𝐞𝐫𝐠𝐞 𝐒𝐲𝐬𝐭𝐞𝐦𝐬 Building conference call systems with participant management and call merge functionality. 🔔 𝐂𝐚𝐥𝐥 𝐑𝐞𝐜𝐨𝐫𝐝𝐢𝐧𝐠 & 𝐓𝐫𝐚𝐧𝐬𝐜𝐫𝐢𝐩𝐭𝐢𝐨𝐧 Call recording implementation with transcription and storage for compliance and analytics. 𝐓𝐰𝐢𝐥𝐢𝐨 𝐖𝐞𝐛𝐡𝐨𝐨𝐤𝐬 𝐮𝐬𝐢𝐧𝐠 𝐏𝐇𝐏 Developing webhook endpoints to handle Twilio events, calls, and messaging workflows. 𝐀𝟐𝐏 𝟏𝟎𝐃𝐋𝐂 𝐑𝐞𝐠𝐢𝐬𝐭𝐫𝐚𝐭𝐢𝐨𝐧 & 𝐂𝐚𝐦𝐩𝐚𝐢𝐠𝐧 𝐒𝐞𝐭𝐮𝐩 Complete setup of brand registration, campaign approval, and compliance for US messaging. 𝐂𝐑𝐌 & 𝐀𝐏𝐈 𝐈𝐧𝐭𝐞𝐠𝐫𝐚𝐭𝐢𝐨𝐧𝐬 Integration of Twilio with CRM platforms like HubSpot, Zoho, Pipedrive, and custom APIs. Why doing API integrations? By doing software integrations, you automate your business saving thousands of dollars on monthly expenses. My experience brings to your operation less total cost. Looking forward to connect. Thanks Anil

  • Twilio
  • Outbound Call
  • Twilio API
  • Plivo
  • WordPress
  • RESTful API
  • API Integration
  • PHP
  • API Development
  • SMS Gateway
  • JSON API
  • Payment Gateway Integration
  • Custom PHP
  • WooCommerce
  • IVR Software
  • SMS Module Setup
  • WhatsApp
  • Campaign Setup
  • SendGrid
  • RingCentral Glip
Thanh T.

Ho Chi Minh City, Vietnam

$40/hr
4.5
139 jobs

- UTILIZING AI TECHNOLOGIES FOR THE DEVELOPMENT, TESTING, OPTIMIZATION, AND INTEGRATION OF PRE-EXISTING VOIP SYSTEMS WITH EXTERNAL SERVICES AND PLATFORMS. - I have more than 16 years to work as system administrator, deploy server, maintenance system base on: asterisk, voip, avaya, freeswitch, kamailio, opensip..... - Developed many VOIP solutions, system for customer over the world as: voicemail system, conference systems, IVR systems, calling card system. - Django developer: Develop e-commercial sites, CMS sites, API systems and more - AngularJS developer, one page applications. - etc.

  • Node.js
  • HTML
  • JSON
  • Python
  • Perl
  • PHP
  • SQL
  • HTML5
  • NoSQL Database
  • SOAP
  • SQL Programming
  • phpBB
  • Linux System Administration
  • PostgreSQL Programming
  • MySQL Programming
Nimit P.

Ahmedabad, India

$20/hr
4.8
26 jobs

Hi Guest, First of all, thanks for visiting our profile. I am doing freelancing since 2010 and my expertise on complete VoIP solution including Freeswitch, Asterisk, PJSip, Opensips and Kamailio. I just recently launched a company which is not offering only VoIP solution but Zeus in Web Development(PHP, WordPress etc), Mobile App Development(Android & iOS). We are a team of members having extensive knowledge of all the services we are offering. We have successfully completed many projects delivered competent results with 100% accuracy with lifetime free support. To keep in mind 100% availability, Our dedicated manager is always online to make sure our client will face no more difficult to ask any query at any time. Let me mentioned the technologies which are our core strength listed below: - Development of Linphone Mobile VoIP Diallers - Development of PJSIP Mobile VoIP Diallers - Installation, development, customization, and maintenance of Asterisk,FreeSwitch Switch,Kamalio and OpenSIPs Servers - Android app development - iOS app development - Flutter Cross Platform App Development - Electron App Development - Web application development - ReactJS and ReactNative development for web and mobile applications - Testing and bug fixing for existing applications Consulting for ongoing projects Project consulting for Android, iOS, ReactJS, Asterisk, FreeSwitch, OpenSIPs, Kamailio, ASTPP, RTPengine, MediaProxy, RTPproxy, FreePBX, and A2Billing Expertise in developing Flutter WebRTC applications Expertise in developing ReactNative WebRTC applications Our price is very reasonable which allows us to work with us. Please share your requirement today only with us to check our capabilities to take your experience on the next level. To name a few tools & technologies that I have worked on: • High-level languages: C++, Objective C, Java, Python, PHP • IDEs: Xcode, Android Studio, Eclipse • Version Control & CI: SVN, Git, Perforce, Bitbucket, Jenkins • DBMS: MS SQL, MySQL, Oracle, PostgreSQL, MongoDB • Frameworks: Django, Zend, Magento, Django REST • Management tools: VersionOne, Jira, Trac, MS Project, MS Visio, XMind, Bugzilla, Balsamiq • Amazon Web Services (AWS) - EC2, S3, SQS, SNS, RDS, CloudTrail, Cloudfront

  • FreeSWITCH
  • PHP
  • WordPress
  • VoIP Administration
  • Asterisk
  • Session Initiation Protocol
  • VoIP
  • FreePBX
  • iOS Development
  • VoIP Software
  • Android App Development
  • iOS
  • WebRTC
  • VICIDIAL
  • Call Center Management
Omid Reza M.

Berlin, Germany

$70/hr
5.0
26 jobs

Senior VoIP Engineer with deep expertise in FreeSWITCH, Asterisk, Kamailio, OpenSER, Anynode SBC, and AudioCodes. Skilled in designing, implementing, and integrating Voice AI Agent solutions within telephony systems, leveraging platforms such as VAPI, LiveKit, and Pipetcat to enable intelligent, real-time voice interactions.

  • FreeSWITCH
  • Linux System Administration
  • Asterisk
  • PHP
  • A2Billing
  • Kamailio
  • VICIDIAL
  • FreePBX
  • Zabbix
  • VoIP

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At A Glance: FreeSWITCH

Communication is a vital part of the business world. The Internet has provided a wide and varied toolkit for communication through the development of various multimedia technologies, such as voice over Internet protocols, online chatting, and video chatting. These technologies can be combined with traditional telephony to create fully functional communication systems to fit the needs of any size of company. FreeSWITCH is open-source software designed to allow the interconnection of various communication protocols, providing a scalable, multi-platform communication solution for any communication needs. A FreeSWITCH specialist can help you optimize the FreeSWITCH software for your business or project.

A FreeSWITCH specialist is a communications professional with experience in a variety of telephone protocols, voice messaging services, text, and other media formats. A FreeSWITCH specialist can be leveraged as a consultant, helping you identify the needs of your business, developing suggestions and communication solutions, or being relied on to manage and optimize your communication network independently. FreeSWITCH specialists can also embed FreeSWITCH features into websites or webpages, as well as have the software operate as a standalone application. Working with a specialist is an effective way to manage and organize all the different communication components of your business, and since FreeSWITCH is open source, a skilled expert can collaborate with you to implement a highly customized solution for you or your business. Hiring a freelance specialist on Upwork reduces and simplifies the way you and your business communicate.