Hire the Best Twilio API Developers in California

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Christian G.

Glendale, California

$50/hr
4.9
74 jobs

I help U.S. businesses navigate SMS approval, deliverability, and compliance requirements - reducing the risk of carrier rejections, blocked traffic, and regulatory issues. I specialize in A2P SMS compliance and deliverability, including 10DLC registration, Toll-Free Verification (TFN), and TCPA/CTIA consent audits, as well as diagnosing carrier-level delivery problems. My work focuses on aligning SMS programs with current carrier and regulatory expectations so they can operate and scale responsibly in the U.S. market. If your messages are being rejected, filtered, or delayed - or you’re unsure whether your consent flow and use case will withstand carrier or legal review—I can help assess and correct the underlying issues. What I Do • 10DLC brand & campaign registration (new submissions, rejections, reclassifications) • Toll-Free Verification (TFN) setup and resubmissions • TCPA / CTIA compliance audits (opt-in flows, disclosures, opt-out handling) • SMS deliverability diagnostics (carrier filtering, content flags, throughput limits) • Platform-specific guidance (Infobip, Twilio, GoHighLevel, ClickSend, SimpleTexting) • Compliance-aware SMS automation (webhooks, triggers, rate-limiting, quiet hours)

  • Twilio
  • SMS
  • Lead Generation
  • Mobile Marketing
  • Compliance Consultation
  • Regulatory Compliance
  • Mobile Marketing Automation
Brent R.

Alameda, California

$99/hr
4.5
84 jobs

Expert Twilio & AI Conversational Solutions Developer | Top 1% Expert-Vetted Talent AI Communication Solutions Architect specializing in Twilio integrations and conversational AI tools that transform customer interactions. As an Expert-Vetted Talent (top 1% on Upwork), I help businesses implement intelligent communication systems that deliver measurable results. I combine deep technical expertise with strategic consulting to create solutions that solve real business problems. My Expertise: Twilio Development & Integration Specialist - Full-stack Twilio platform development with 7+ years of experience - Custom SMS, voice, and messaging workflows that scale with your business - Integration of Twilio services with existing business systems and CRMs AI Conversational Tool Development - Custom chatbots, SMS bots, and voice assistants powered by ChatGPT and other LLMs - Multi-channel AI solutions (phone, SMS, WhatsApp, Facebook Messenger, live chat) - Intelligent IVR systems that improve customer experience and operational efficiency Strategic Communication Consultant - Process analysis to identify automation opportunities - ROI-focused solutions that deliver measurable business impact - Clear roadmaps for implementing AI communication strategies Results I've Delivered: - Developed a custom missed call Slack app that reduced agent response time from 30+ minutes to under 3 minutes, improving customer satisfaction and sales conversion - Created custom screen pop tools for Five9 that decreased call handling time by 6 seconds per call and reduced agent training by 4 hours per client - Built React components and plugins for custom call-center dashboards that streamlined agent workflows - Implemented multi-channel messaging flows with AI integration that provide 24/7 customer support Technology Stack: Twilio, ChatGPT (OpenAI API), Claude API, Ruby, JavaScript, React, Node.js, Bootstrap, WhatsApp Business API, Facebook Messenger API, Slack API, Airtable API, Monday.com API, Pipedrive API, Make.com API, Zapier API, Hubspot API, and more. I bring both technical expertise and business acumen to every project. Whether you need implementation support or strategic consulting on your communication systems, I'm here to help you leverage AI and cloud communication platforms to achieve your business goals. Let's discuss how we can transform your customer interactions.

  • Twilio API
  • Twilio
  • JavaScript
  • API Integration
  • React
  • IVR Software
  • Chat & Messaging Software
  • Chatbot
  • Product Strategy
  • Product Launch
  • Product Management
  • Product Roadmap
  • ChatGPT
  • Azure OpenAI Service
  • OpenAI Codex
Andres M.

San Diego, California

$150/hr
5.0
24 jobs

Hi, my name is Andres. I am a full stack developer with over 15 years of experience building web applications from the ground up. I specialize in data driven AngularJS and Angular applications with NodeJS backends. If you are passionate about your vision, let's talk, I will be happy to help make it a reality.

  • Twilio API
  • MySQL
  • Angular
  • AngularJS
  • Web Application
  • Bootstrap
  • CSS
  • JavaScript
  • API Integration
  • SCSS
  • Stripe
  • Database Architecture
  • Database Design
  • Azure App Service
  • SendGrid
Ahsan H.

Sacramento, California

$65/hr
5.0
2 jobs

✨ Senior API Integration & AI Automation Specialist | LLM & OpenAI Expert | Voice AI | Twilio | VoIP | RingCentral ✨ Core Expertise: API Integrations • GHL Automation • AI Agents • LLM Applications • OpenAI API • CPaaS system • Vapi • Twilio • RingCentral • VoIP • Payment Gateways • ERP Systems • Chatbots • Microservices • Marketing Tools • Healthcare Systems • Financial Platforms • Middleware • CRM • Social Media APIs • Databases • E-commerce • Workflow Automation • HubSpot • Salesforce • QuickBooks API • NetSuite Integration • Odoo ERP Development • Zoho Books API I help businesses connect platforms, automate workflows, and build scalable AI-powered systems using APIs, LLMs, and modern backend technologies. My expertise includes API integrations, AI agents, OpenAI-powered applications, payment gateway systems, CRM/ERP synchronization, workflow automation, and custom middleware development. I focus on building reliable integrations that improve operational efficiency, reduce manual work, and scale smoothly with business growth. Core Expertise: ✔ API Integrations ✔ AI Agents & LLM Applications ✔ OpenAI API & Automation ✔ Payment Gateway Integrations ✔ QuickBooks & Xero Integrations ✔ CRM & ERP Systems ✔ Twilio, WhatsApp & Messaging APIs ✔ Webhooks & Microservices ✔ Healthcare & Financial Systems ✔ E-commerce Integrations ✔ Custom Backend Development Tech Stack: Node.js • NestJS • Python • FastAPI • Express.js • PostgreSQL • MongoDB • Redis • REST APIs • GraphQL • Docker • AWS • Firebase I’ve worked on integrations involving payment platforms, accounting systems, AI chatbots, communication APIs, SaaS products, and enterprise workflow automation systems. Why clients work with me: ✅ Clean and scalable architecture ✅ Fast communication and reliable delivery ✅ Business-focused solutions ✅ Long-term maintainable systems ✅ Strong debugging and problem-solving skills If you need an experienced developer to build secure integrations or AI-powered automation systems, feel free to invite me to your project or schedule a quick chat. Full Stack Developer | MERN Stack Developer | Base44 Developer| React.js Developer | Next.js Developer | Node.js Developer | JavaScript Developer | Web Application Development | Custom Web Applications | SaaS Development | MVP Development | Startup Developer | Scalable Web Applications | Backend Developer | Frontend Developer | API Integration | REST API Development | GraphQL API | API Developer | Third-Party Integrations | Payment Gateway Integration | Stripe | PayPal | CRM Integration | HubSpot | Zoho| Salesforce | Dashboard Development | Admin Panel Development | Automation Developer | Workflow Automation | Zapier | Make | Integromat | n8n | Database Design | MongoDB | PostgreSQL | MySQL | Firebase | Supabase | Redis | Real-Time Applications | Web Performance Optimization | Responsive Web Design | Tailwind CSS | Modern UI/UX | Cloud Deployment | AWS | Vercel | Docker | CI/CD Pipelines | GitHub Actions | Serverless Architecture | Microservices Architecture | Secure Authentication | JWT | OAuth) | Role-Based Access Control | RBAC | SaaS Platforms | Marketplace Development | Booking Systems | ERP Systems | CRM Systems | Scalable Backend Systems | Twilio API | WhatsApp API | SMS API | Messaging API | VOIP Systems | Cloud Telephony | Call Automation | Auto Dialer Systems | IVR Systems | Call Routing | WebRTC | SIP Integration | Call Recording & Analytics | CRM Calling Integration | QuickBooks Online Integration | QBO Automation | Accounting Workflow Automation | Financial Data Sync | Invoicing & Payments Sync | Expense & Transaction Automation | Bookkeeping Integrations | POS to QuickBooks Sync | Payroll & Reporting Automation | NetSuite Integration | Odoo ERP Development | Zoho Books API Integration | ERP & Accounting Software Integrations | CPaaS | Communications Platform as a Service.

  • Twilio
  • React
  • Django
  • Vue.js
  • Node.js
  • Xero
  • Shopify
  • QuickBooks Online
  • Supabase
  • Data Visualization
  • Python
  • Automation
  • SMS Gateway
  • OpenAI API
  • Payment Gateway Integration
  • AI Agent Development
  • Make.com
  • Telephone System
  • VoIP Software
Byron W.

San Francisco, California

$80/hr
5.0
1 jobs

Hi there! I’m a seasoned Full-Stack Software Developer with over 20 years of experience in the tech industry. I specialize in creating robust, scalable, and efficient web applications using modern technologies like React and Amazon Web Services (AWS). My extensive background in both front-end and back-end development allows me to deliver comprehensive solutions that meet my clients' unique needs. What I Offer: Fullstack Development: Expertise in building end-to-end web applications, from designing intuitive frontends to developing powerful backend services. Frontend Excellence: Proficient in React, HTML, CSS, and JavaScript to create responsive and user-friendly interfaces. Backend Mastery: Strong skills in Node.js, Java, and other backend technologies to build scalable and secure server-side applications. Cloud Services: Deep knowledge of AWS services, including EC2, S3, Lambda, RDS, and more, to design and deploy cloud-based solutions. Agile Development: Experience in agile methodologies to ensure efficient project management and timely delivery. Collaboration: Excellent communication skills and a collaborative approach to working closely with clients, designers, and other stakeholders. Key Projects: Oncue: Directed the engineering team to implement Twilio Flex and Dropbox Sign solutions, enhancing customer interaction and streamlining workflows. Healthline Media: Led the development of a new web platform using Node.js and React.js on AWS, improving performance and scalability. Constant Contact: Guided the iOS development team, implemented CI/CD pipelines, and ensured seamless deployment of mobile applications. Skills: Frontend: React, HTML, CSS, JavaScript, TypeScript Backend: Node.js, Java, Spring, SQL, NoSQL Cloud Services: AWS (EC2, S3, Lambda, RDS), GraphQL, Next.js Tools: Git, Docker, Jenkins, Jira, Twilio Methodologies: Agile, Scrum, Continuous Integration/Continuous Deployment (CI/CD) Why Choose Me: I bring a unique blend of technical expertise, project management skills, and a deep commitment to delivering high-quality software solutions. I aim to help you achieve your business objectives by providing reliable, scalable, and user-friendly applications. I am passionate about technology and strive to stay updated with the latest trends and best practices in software development. Let’s work together to bring your ideas to life and drive your projects to success!

  • Twilio
  • Amazon Web Services
  • SQL
  • TypeScript
  • Front-End Development
  • Node.js
  • Relational Database
  • React
  • Stripe API
  • CSS
  • HTML
  • JavaScript
  • Google Ad Manager
Paul M.

Cupertino, California

$75/hr
4.7
491 jobs

Software developer with 20+ years experience. Many of these years in large telecommunication companies. Developed and project managed complex products. I am focused in a few areas. This focus and experience enables quicker turnaround for you. Expert in Twilio. Tier 1 partner of Twilio and recognized by Twilio itself. Expert in complex asterisk PBX setup for multi-extensions, multi-trunks, queues, hunt group, IVR. Complex IVRs, customizations and scripts for asterisk. Large PBX setup using Kamailio as proxy. Expert in developing large distributed systems using Amazon AWS. Expert in Roku. Developed several popular Roku Channels including that of Fortune 100 companies (Details provided on request)

  • Twilio API
  • Twilio
  • PHP
  • Nexmo
  • Asterisk
  • Amazon Web Services
  • FreePBX
  • Plivo
  • Apple TV Application
  • Roku Development
  • Stripe
  • Zoho CRM

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