I am a VoIP and Telephony Engineer with extensive experience in 3CX, VICIdial, Asterisk, FreeSWITCH, Twilio, SIP Trunking, and DID number provisioning. I help businesses build, optimize, and maintain reliable communication systems for call centers, telemarketing operations, and enterprise telephony environments.
My expertise includes PBX installation and configuration, SIP trunk integration, number porting, IVR design, call routing, predictive dialer setup, inbound and outbound call center solutions, and VoIP troubleshooting. I am also experienced with Linux server administration, cloud deployments, and API integrations for voice and SMS applications.
Whether you need a complete call center deployment, 3CX configuration, VICIdial optimization, Twilio integration, SIP troubleshooting, or ongoing telephony support, I can deliver scalable and dependable solutions tailored to your business needs.
Core Skills:
• 3CX PBX Administration
• VICIdial Installation & Management
• Asterisk & FreeSWITCH Development
• Twilio Voice & SMS Solutions
• SIP Trunk Configuration
• DID Number Provisioning & Porting
• Predictive & Power Dialers
• IVR & Call Flow Design
• Linux Server Administration
• VoIP Troubleshooting & Optimization
• CRM & API Integrations
• Call Center Infrastructure Setup
I focus on delivering reliable communication systems that improve efficiency, call quality, and business performance.
3CX, VICIdial, Asterisk, FreeSWITCH, Twilio, VoIP, SIP, SIP Trunk, DID Numbers, PBX, IP PBX, Hosted PBX, Cloud PBX, Telephony, Telecom, Telecommunications, Call Center, Contact Center, Predictive Dialer, Power Dialer, Auto Dialer, Progressive Dialer, Call Routing, IVR, Interactive Voice Response, Call Queue, Ring Groups, Voicemail, Call Recording, Number Porting, SIP Carrier, Voice Gateway, Session Border Controller, SBC, WebRTC, SMS Gateway, Twilio Voice, Twilio SMS, Twilio API, Linux Administration, CentOS, Ubuntu, Debian, Rocky Linux, AlmaLinux, MySQL, MariaDB, PostgreSQL, Apache, Nginx, SSH, VPN, Firewall, Networking, TCP/IP, UDP, RTP, QoS, NAT Configuration, VoIP Troubleshooting, SIP Debugging, SIP Trace, Wireshark, CRM Integration, Salesforce Integration, HubSpot Integration, Zoho CRM, Pipedrive, API Integration, REST API, PHP, Python, Bash Scripting, AGI Scripts, Call Flow Design, Inbound Calling, Outbound Calling, Lead Management, Telemarketing, Cold Calling Systems, Voice Broadcasting, Bulk SMS, DID Provisioning, SIP Registration, Carrier Integration, Call Monitoring, Queue Management, Agent Management, Multi Tenant PBX, Failover Configuration, High Availability, Cloud Deployment, AWS, DigitalOcean, Vultr, Linode, Dedicated Servers, VPS Setup, Server Migration, System Optimization, VoIP Security, Fraud Prevention, FreePBX, Issabel PBX, FusionPBX, Elastix, Yeastar, Grandstream, Fanvil, Yealink, Polycom, Cisco VoIP, Sangoma, OpenSIPS, Kamailio, Voice API, Telecom Consulting, Call Center Setup, VoIP Engineer, Telephony Engineer, SIP Expert, 3CX Expert, VICIdial Expert, Twilio Expert, Asterisk Expert, FreeSWITCH Expert, Linux Server Administrator, Network Engineer, Technical Support, System Administration, Remote Support, Cloud Communications, Unified Communications, UCaaS, Business Phone System, Enterprise Telephony, Call Center Optimization, Dialer Configuration, Lead Campaign Management, Real Time Reporting, Call Analytics, Voice Solutions, Telecom Infrastructure, Contact Center Solutions, VoIP Deployment, PBX Installation, SIP Configuration, DID Management, Call Center Technology, Telecom Solutions
BPO Call Center
Telemarketing
Lead Generation
Sales Lead Lists
Asterisk
3CX
VoIP Software
VoIP Administration
VoIP PBX
VoIP
Twilio
Twilio API
FreePBX
VICIDIAL
Cold Calling
Onyinye A.
Abuja, Nigeria
$5/hr
5.0
2 jobs
If Your Customers Matter to You, Then Who Handles Them Matters Even More.
Most businesses lose clients not because their product is bad, but because their customer experience is inconsistent, slow, or poorly managed.
I’m a Customer Service & Client Experience Specialist with over 12 years of experience helping businesses improve response time, increase retention, recover dissatisfied customers, and turn inquiries into loyal, paying clients.
I don’t just “reply to messages.”
I build systems that improve customer satisfaction and drive revenue.
When you hire a Customer Service Representative, you need someone who will:
- Respond quickly and professionally
- Represent your brand with confidence
- Manage your CRM without supervision
-Track conversations and follow-ups properly
- De-escalate complaints without losing customers
- Support sales and convert warm leads
- Keep your pipeline organized
- Deliver measurable results
That’s exactly what I do. Here is how I will support Your business
Here’s how I approach every role:
✔ Customer Support & Retention
✔ Handle email, chat, and phone support with empathy and efficiency
✔ Resolve complaints before they escalate
✔ Follow structured follow-up systems to reduce churn
✔ Maintain detailed records of all interactions
✔ CRM & Pipeline Management
✔ Update and manage CRM systems daily
✔ Track leads and automate follow-ups
✔ Monitor KPIs and generate performance reports
✔ Improve customer journey workflows
✔ Sales & Lead Conversion Support
✔ Qualify inbound leads
✔ Nurture prospects through structured communication
✔ Cross-sell and upsell where appropriate
✔ Recover dormant or inactive accounts
✔ Team & Process Improvement
✔ Supervise and support junior agents (if required)
✔ Create SOPs for consistent service delivery
✔ Improve response templates and workflows
🛠 Tools & Platforms I’m Proficient In;
- CRM Systems (HubSpot, Zoho, Salesforce, and similar platforms)
- Zen-desk
- Freshdesk
- Intercom
- Slack
- Trello / Asana
- Google Workspace
- Microsoft Office Suite
- Email management systems
- Sales tracking dashboards
I adapt quickly to new systems and workflows.
Proven Results & Achievements
- Improved customer conversion rates through structured CRM follow-ups
- Successfully reactivated dormant client accounts
- Led sales and customer service teams to consistently meet weekly targets
- Increased customer satisfaction through proactive communication
- Managed high-value clients and reduced payment defaults through strategic follow-ups
I treat your customers like they are my own.
If you're looking for someone who can improve your customer experience, protect your brand reputation, and contribute to revenue growth, I’m ready to get started.
Customer Service
Phone Communication
Technical Support
Online Chat Support
Telemarketing
Ticketing System
Zoho CRM
Zendesk
Intercom
Slack
HubSpot
Jennifer A.
Lagos, Nigeria
$15/hr
4.6
7 jobs
I am a result-driven Customer Success and Business Operations Professional with over 6 years of experience managing customer/client relationships, cross-team communication, and providing excellent customer service. I enjoy finding creative solutions across products, customer service, and business development initiatives.
✨Customer Service
✨Escalation Management and Complaint Resolution
✨Business Account Onboarding
✨Virtual Assistance
Skilled in the following;
🔹Email Support
🔹Cold/warm calling
🔹Ticketing System/ Online Chat Support
🔹E-commerce - Shopify
Want a smart and prudent workflow process management?
I am highly skilled in managing projects from start to completion.
CERTIFICATIONS
🔹Google Project Management Professional
🔹Business Writing Skills & Email Etiquette
🔹Brand Management
I look forward to working with you.
Cheers!
Technical Support
Customer Service
Phone Communication
Lead Generation
Email Etiquette
Calendar Management
Agile Project Management
Cold Calling
Administrative Support
Salesforce CRM
CRM Automation
Process Improvement
Elvis I.
Asaba, Nigeria
$15/hr
5.0
2 jobs
⭐⭐⭐⭐⭐ "Elvis built us an AI Voice Agent that answers calls, qualifies leads, books appointments, and syncs everything directly into our CRM. The setup was smooth and immediately reduced workload for our team.
Whether you need AI Receptionist, AI Voice Agent, AI Phone Agent, Conversational AI System, CRM Automation, or a complete AI-Powered Business Workflow.
I help non-technical founders, agency owners, and operational businesses eliminate missed calls and automate scheduling with ultra-low-latency AI Voice Receptionists.
If your business relies on phone communication but struggles with dropped leads, manual booking friction, or high overhead costs, I build custom human-like voice agents that answer 24/7, qualify leads, and write data directly to your CRM.
Core Specializations & Architecture
I specialize in the technical setup and deployment of production-grade conversational AI systems using a cutting-edge voice tech stack:
Voice Orchestration: Retell AI & Vapi (Optimized for sub-500ms response latency)
Telephony & Infrastructure: Twilio API integration, custom SIP trunking, and phone number provisioning.
Backend & Automation: Advanced development for custom webhooks, complex multi-step workflows via Make and LLM orchestration.
Conversational Logic: Smart Chatbot Development featuring advanced prompt engineering, dynamic memory retrieval, and guardrails to prevent hallucinations.
Audio Quality & Realism: Pro-tier Audio Production, precise behavioral pacing, and custom voice character tuning to make interactions sound completely natural.
Solutions Built for Conversion
AI Voice Receptionist: Fully autonomous inbound call handling, intelligent customer routing, and live FAQ resolution.
Booking Assistant: Dynamic, calendar-aware agents that cross-reference availability via API and schedule appointments directly into your system in real time.
AI Voice Agent (Outbound): Instant speed-to-lead follow-ups, automated appointment reminders, and database reactivation campaigns.
The "Build-and-Teach" Framework
I don’t just drop code and disappear. Every system I deploy follows a strict delivery standard:
Discovery & Prompt Mapping: Aligning the agent's voice acting and conversational style with your brand persona.
Deep CRM Integration: Syncing call data, transcription analysis, and tags directly to your CRM (GoHighLevel, HubSpot, Airtable, etc.)
System Documentation: You receive complete backend technical documentation and a personalized video walkthrough so your team can easily manage the system.
Let’s turn your phone lines into an automated, revenue-generating asset.
Please ignore, for SEO purposes
AI Agent, AI Voice Agent, AI Phone Agent, AI Receptionist, Voice AI, Conversational AI, Agentic AI, Generative AI, LLM, Artificial Intelligence, AI Chatbot, AI Bot, Virtual Agent, Voice Bot, AI Automation, AI Engineer, Automation Specialist, Prompt Engineering, Conversational Design, Conversation Flows, System Prompt, Prompt Optimization, LLM Orchestration, Retrieval-Augmented Generation, RAG, Knowledge Base, Real-Time Voice AI, Low Latency, Human-Like AI, Natural Conversation, Turn-Taking ,Interruption Handling, Bilingual AI Agent, Scalable AI, Multi-Tenant SaaS, SaaS Development, Inbound Calls, Outbound Calls, Cold Calling, Cold Outreach, Outbound Sales, Telemarketing, Lead Generation, Lead Qualification, Appointment Setting, Appointment Booking, Customer Service, Customer Support, Call Routing, Warm Transfer, CRM Automation, CRM Integration, Pipeline Management, Workflow Automation, Business Process Automation, Review Automation, Customer Acquisition, Prospect List Building, Data Scraping, Data Mining, Market Intelligence, Lead Enrichment, Call Transcription, AI Generated Summaries, Compliance Verification, Voice Cloning, Voice Acting, Voice Over, Audio Production, Speech-to-Text, STT, Text-to-Speech, TTS, AI Voice Testing, Quality Assurance, Software Testing, Integration Testing, Deployment Automation, Latency Optimization, API Integration, REST API, Webhook Setup, Full Stack Development, Backend Development, Dashboard Development, Database Management, Technical Audit, Vapi, Vapi AI, Retell AI, Bland AI, ElevenLabs, Synthflow, OpenAI API, GPT-4, GPT-4o, ChatGPT, Claude API, Claude Sonnet, Claude Haiku, Anthropic API, Gemini Flash, Gemini Voices, Deepgram, Deepgram Nova-3, Whisper, LiveKit, Twilio, Twilio Voice, Twilio SIP, VoIP, SIP Trunk, SIP Integration, Asterisk, VICIdial, Dialpad AI Agents, n8n, Make, Zapier, Pabbly, Supabase, Supabase pgvector, PostgreSQL, Pinecone, Redis, Firebase, Firestore, Airtable, Google Sheets, Google Docs, Lead Qualification Automation, Appointment Reminder Automation, Customer Engagement, Client Support, Online Chat Support, Reporting Analytics, Workflow Architecture, Webhook Configuration, SaaS Automation, AI Calling, Call Center Automation, Phone Support, AI Customer Support, AI Lead Generation, AI Appointment Setter.
AI Agent Development
Artificial Intelligence
Chatbot Development
English
Voice Acting
AI Development
Conversational AI
Phone Communication
AI Bot
AI Chatbot
API Integration
Audio Production
Cold Calling
Scheduling
Make.com
Sales
Outbound Sales
CRM Automation
Twilio API
Python
Gold A.
Ondo, Nigeria
$15/hr
5.0
10 jobs
𝐑𝐢𝐧𝐠𝐂𝐞𝐧𝐭𝐫𝐚𝐥 & 𝐓𝐰𝐢𝐥𝐢𝐨 𝐄𝐱𝐩𝐞𝐫𝐭 | 𝐕𝐨𝐈𝐏, 𝐈𝐕𝐑, 𝐒𝐌𝐒 & 𝐀𝟐𝐏 𝟏𝟎𝐃𝐋𝐂
Twilio Developer | RingCentral & Telnyx Integration | AI Voice Receptionist Specialist
I'm a Twilio developer specializing in building reliable, automated phone and messaging systems for businesses that can't afford missed calls or slow response times. Twilio is my core platform I build Twilio Voice, Twilio Studio, Twilio Flex, and Twilio SMS solutions daily, alongside RingCentral and Telnyx integrations for businesses that need alternative or multi-carrier setups.
Twilio & Telephony Development:
🔹 Twilio Voice, Twilio Studio & Twilio Flex builds IVR, call routing, call flows
🔹 Twilio SMS & WhatsApp API integration
🔹 RingCentral API integration & workflow automation
🔹 Telnyx voice & SIP trunking for cost-efficient infrastructure
🔹 A2P 10DLC registration twilio and Telnyx campaign/brand approval so SMS actually delivers
AI Voice Receptionist Development:
🔹 AI-powered receptionists built on Twilio's voice infrastructure answer, qualify, and route calls 24/7
🔹 Conversational AI agents that sound natural, not robotic
🔹 CRM-connected systems (GoHighLevel, HubSpot, Salesforce) so every call and lead is logged automatically
Why clients choose me:
Twilio is where I spend most of my time I know its quirks, its APIs, and how to get campaigns approved without carrier filtering issues. RingCentral and Telnyx round out my stack when clients need flexibility outside Twilio's ecosystem.
Tell me what your phone system is missing let's fix it with Twilio.
The Problem:
Most businesses lose leads not because they don't have enough traffic — but because they can't answer the phone fast enough. Calls go to voicemail. SMS gets filtered by carriers because A2P 10DLC wasn't registered correctly. After-hours calls just... disappear. Every missed call is a customer calling your competitor next.
The Solution:
I build always-on phone systems using Twilio, RingCentral, and Telnyx backed by AI voice receptionists that answer instantly, qualify the caller, and route them correctly, 24/7. No more missed calls. No more SMS getting blocked by carriers. No more leads slipping through after hours
.
Here's what that looks like in practice:
ProblemSolutionCalls go unanswered after hoursAI receptionist answers 24/7, captures lead infoSMS messages get filtered/blockedA2P 10DLC registration done correctly the first timeStaff overwhelmed during peak call timesTwilio/RingCentral call routing & overflow automationLeads go cold waiting for a callbackInstant missed-call text-back + auto-bookingDisconnected systems (CRM, calendar, phone)Everything connected Twilio + GoHighLevel/HubSpot/Salesforce
Twilio, RingCentral, Telnyx, Vonage, Plivo, Bandwidth, SignalWire, 8x8, Nextiva, Zoom Phone, Aircall, Dialpad, Five9, Genesys, Amazon Connect Twilio Studio, Twilio Flex, Twilio Functions, Twilio Voice, Twilio SMS, Twilio WhatsApp API, Twilio Conversations API, Twilio Lookup, Twilio Verify, Twilio Proxy, Twilio Sync, Twilio TaskRouter, Twilio Programmable Voice, Twilio SendGrid RingCentral API, RingCentral MVP, RingCentral Embeddable, RingCentral Webhooks, RingCentral Engage, RingCentral Contact Center, RingCentral Video AI Voice Agent, AI Receptionist, AI Phone Agent, Conversational AI, Voice AI, Voicebot, Chatbot Development, NLP, Natural Language Understanding, Speech to Text, Text to Speech, OpenAI API, ChatGPT API, GPT-4 Integration, Whisper API, ElevenLabs, Deepgram, Vapi AI, Bland AI, Retell AI, LLM Integration, Prompt Engineering, AI Call Routing, AI Appointment Setter, AI Lead Qualification, Voice Cloning, Real-Time Voice Agent SIP Trunking, VoIP Development, IVR Development, Interactive Voice Response, Call Routing, Call Forwarding, Click-to-Call, Call Recording, Call Tracking, Call Analytics, Predictive Dialer, Auto Dialer, PBX Setup, Cloud PBX, WebRTC, Number Porting, DID Numbers, Toll-Free Number Setup, Inbound Call Automation, Outbound Calling Automation, Call Center Automation, Contact Center Solutions, Omnichannel Communication A2P 10DLC, A2P 10DLC Registration, Carrier Registration, SMS Campaign Approval, Toll-Free Verification, SMS Marketing Compliance, TCPA Compliance, CTIA Compliance, Brand Registration, Campaign Use Case Approval, SMS Throughput, Short Code Registration, 10DLC Brand Vetting, Carrier Filtering CRM Integration | Zapier | Make com | n8n | GoHighLevel | HubSpot | Salesforce | Missed Call Text Back | 24/7 Phone Answering | Virtual Receptionist | AI Front Desk | Appointment Scheduling Automation | Lead Response Automation | Voicemail Transcription | Real Estate Call Automation | Medical/Dental Office AI Receptionist | Law Firm Call Intake | Home Services & HVAC Call Automation | Node.js/Python Twilio Integration | REST API Development | Phone System Consulting | Legacy Phone System Migration
Call Center Software
Call Center Management
RingCentral Glip
VoIP Administration
Twilio
Twilio API
SMS Module Optimization
IVR Software
API Integration
Marketing API Integration
Technical Support
End User Technical Support
SMS Module Setup
HighLevel
VoIP
VoIP PBX
VoIP Software
SMS
AI Chatbot
Automated Workflow
Akinbode G.
Akure, Nigeria
$30/hr
4.8
83 jobs
I help businesses across real estate, healthcare, e-commerce, and agencies get Twilio A2P 10DLC approved, connect their CRM and communication tools into one working system, and keep SMS, voice, and lead follow up running without gaps. $8K+ earned on Upwork. Messages fixed, campaigns approved, systems running.
Most businesses run two or three tools that were never built to talk to each other, a CRM, a phone system, a booking tool, and messages or leads get lost in the gap between them. I build the webhook and API layer that keeps those systems synced in real time, whether that is Follow Up Boss and GoHighLevel for a real estate team, HubSpot and Twilio for a healthcare clinic, or a custom CRM and SMS platform for an e-commerce brand. The result is the same either way: nothing sits waiting in a system nobody is watching.
WHAT I SET UP AND FIX FOR YOU:
• A2P 10DLC registration, TCR campaign approval, and SMS compliance under TCPA and carrier rules
• GoHighLevel workflow automation, pipeline management, and AI conversation setup
• CRM to CRM and CRM to communication tool integrations, including Follow Up Boss, Lofty, HubSpot, Pipedrive, and Zoho
• Twilio API integration, IVR flows, call routing, and webhook based SMS automation
• Voice AI and conversational AI setup using VAPI, Lofty, GoHighLevel AI, and custom prompt engineering
• CRM automation and marketing automation using n8n, Zapier, and Make
• Lead routing and speed to lead systems for sales teams running multiple lead sources
• RingCentral and VoIP administration, including SIP setup and call flow design
• WhatsApp Business API and multi channel messaging systems
• REST API, webhook, Node.js, and JavaScript integrations for custom builds standard tools cannot handle
I work across real estate, healthcare, e-commerce, and agency clients, building whatever SMS, voice, or CRM connection your business actually needs.
If your A2P registration is stuck, your systems aren't talking to each other, or your Twilio setup needs fixing: send me a message or invite me to your job. Let's get it working the right way.
GoHighLevel, Twilio API, A2P 10DLC, Follow Up Boss, CRM Automation, Workflow Automation, Webhook Integration, Voice AI, SMS Automation, Lead Routing, Twilio Voice, RingCentral, IVR Setup, Zapier, Real Estate, Lofty.
Twilio
Twilio API
HighLevel
VoIP Software
CRM Automation
Marketing Automation
SMS
API Integration
Lead Generation
AI Agent Development
Automation
n8n
Real Estate
Administrative Support
Node.js
Zapier
WhatsApp
RingCentral Glip
Campaign Setup
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