Hire the Best Chatbot Developers in California

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Steven A.

Lawndale, California

$100/hr
5.0
127 jobs

I design and build production AI automation systems — from chatbots and voice agents to document workflows, CRM pipelines, and GPT-powered reporting — helping businesses reduce manual work, cut costs through automation, and drive measurable growth. With 10+ years in automation and 8+ years building AI systems, I deliver end-to-end solutions that streamline operations, enhance customer engagement, and scale real business outcomes. Whether you’re optimizing customer support, improving lead generation, or automating internal workflows, I create systems that go far beyond basic chatbots. About Me: 🔹 10+ years experience in digital automation. 🔹 8+ years of AI and chatbot experience. 🔹 Microsoft Certified Azure AI Engineer. 🔹 Delivered 50+ AI-powered automation systems with measurable results. 🔹 Experience building AI-assisted trading and analytics systems. 🔹 Recognized as Top 1% of Talent on Upwork, ensuring high-quality and reliable delivery. ➡️ Let’s discuss your project and build a tailored AI automation system for your business. 🌟 🌟 🌟 🌟 🌟 "Best Chatbot Engineer! Unbelievable working with Steven. He literally transformed our project. So excited for what he created!” 🌟 🌟 🌟 🌟 🌟 “Steven is amazing to work with. Incredibly helpful, sharing insights, ideas, and possibilities. Very cooperative, responsive, and creative in his problem-solving approach to work. He explains his processes in detail and is very patient along the way with all the questions you may have.” 🌟 🌟 🌟 🌟 🌟 "Steven was amazing to work with! He's so knowledgable and excellent at what he does. Will definitely hire him again for future projects. Thanks, Steven!” Industries I’ve Helped My AI automation systems have delivered measurable success in these industries: 🔹 Healthcare: Therapy Simulator Automation System. 🔹 Education: GPT lesson plan generator. 🔹 E-commerce: Sales and support chatbots. Certifications: 🔹 Microsoft Certified Azure AI Engineer Associate - Microsoft - 2022 🔹 Mobile App Design Certification - Coastline College, Fountain Valley, CA - 2018 Skills: 🔹 Automation: Workflow automation, API integrations, CRM pipelines, document AI, vector search (Azure Cognitive Search / embeddings) 🔹 Programming: JavaScript, Node.js, Kotlin, React 🔹 Chatbots: GPT, Dialogflow, Azure, Lex, Watson, Messenger, Twilio/SMS, Instabot, Tidio, ManyChat 🔹 Frontend: React, HTML, CSS, JavaScript 🔹 Databases: Google Cloud, Firebase, Azure, AWS 🔹 Backend: Node.js, Firebase Functions, Azure Cognitive Services, GPT 🔹 Cloud: GCloud, AWS, Azure Notable Projects: 🔹 AI Trading Automation System: Built GPT-assisted market analysis + pattern recognition pipelines using multi-year candle data, generating predictive signals with ~60% directional accuracy in live tests. 🔹 Voice Automation System for Surveys:
Conducted interviews and surveys over the phone (built with GCP and Azure) — Reduced survey time by 50%. 🔹 Therapy Simulator: Chatbot
GPT-powered voice chatbot allows students to train in psychology with mock patients. 🔹 K-12 Lesson Plan Generator: Generated 12–15 pages of lesson material for teachers — Saved 20+ hours per week of manual work. 🔹 University Content Automation System:
GPT API chatbot generated lectures and content for an online university — Streamlined operations, saving 20+ hours per week. 🔹 Customer Support and Lead Generation Chatbot:
Built using GPT, Dialogflow, and Twilio to handle customer support and lead generation via SMS — Saved $40,000 annually through automation. 🔹 Orchestration Chatbot
Combined Dialogflow, Lex, and Watson NLU recognition for seamless, multi-platform orchestration. 🔹 Persuasive Sales Agent Chatbot
Utilized reinforcement learning to tailor messages based on user likelihood to respond, boosting engagement. Tags: Marketing Automation, Emerging Tech, Full Stack Development, Back-End Development, AI Automation, GPT, AI-Powered automation, Dialogflow, Dialogflow CX, Azure, GCP, Google Cloud, Voice Chatbot, SMS, Twilio, Messenger, Automation, React, UX, LLM Chatbot

  • Chatbot Development
  • Chatbot Flow Design
  • Chatbot
  • JavaScript
  • Machine Learning
  • Natural Language Processing
  • Chatbot Integration
  • Firebase Cloud Firestore
  • Productivity Chatbot
  • ManyChat
  • Node.js
  • Dialogflow
  • Firebase
  • Marketing Automation
  • Artificial Intelligence
Sohail M.

Lake Forest, California

$30/hr
5.0
9 jobs

AI Agent Developer building Voice AI agents, AI chatbots, RAG pipelines, and AI automation using OpenAI API, Python, FastAPI, and n8n. I connect AI systems to CRMs, calling platforms, and knowledge bases to solve real business problems, not demos. Every project I've delivered carries a 5-star rating and a client endorsement. 📈 Selected projects ✅ AI fraud detection platform (Next.js, Stripe) cutting chargebacks by up to 98% using behavioral pattern recognition and machine learning instead of static rule engines, PCI DSS compliant ✅ Inbound and outbound Voice AI platform on Twilio, Retell AI, and ElevenLabs, cutting call handling time by 35% and improving customer satisfaction by 18% through live transcription and intelligent routing ✅ Multi-channel AI chatbot using OpenAI API, LangChain, and Pinecone, integrated with Bitrix24, Zoho, and Salesforce, lifting outreach efficiency by 60% through automated lead qualification and human handoff ✅ RAG-powered multilingual knowledge platform with vector database retrieval, cutting manual document search time and delivering low-hallucination answers across business knowledge bases ✅ n8n automation workflows connecting LLMs with CRMs, Zendesk, HubSpot, and internal systems, removing repetitive manual work from daily operations 🛠️ Built with: OpenAI API, RAG, Pinecone, n8n, Twilio, Retell AI, ElevenLabs, LangChain, FastAPI, Python, MongoDB, Next.js, React 💬 Tell me what you're building. I'll tell you honestly whether it needs a voice agent, a chat agent, or both.

  • Chatbot Development
  • Automatic Speech Recognition
  • Natural Language Processing
  • Python
  • AI Chatbot
  • Conversational AI
  • AI Agent Development
  • Retrieval Augmented Generation
  • Large Language Model
  • Vector Database
  • LangChain
  • ElevenLabs
  • n8n
  • Next.js
  • FastAPI
  • Twilio API
  • AI App Development
  • MongoDB
  • PostgreSQL
Gino D.

Riverside, California

$30/hr
5.0
1 jobs

Ai automation specialist creating custom botpress agent's to streamline client workflows & leads and Tech Generalist Expert in FlutterFlow Firebase & Ai tools Delivering fast quality results

  • Chatbot Development
  • AI Agent Development
  • AI App Development
  • ChatGPT
  • Smartphone
  • Web Development
  • Mobile App
wei cheng wilson K.

Pasadena, California

$39/hr
4.6
59 jobs

AI RAG LLM Chatbot DAPP Telemedicine Healthcare Fintech Developer Looking for Blockchain AI developer in the finance, healthcare and ecommerce vertical? Look no further: +10 years of Automation experience at Siemens and years of experience at Deloitte and Unilever in finance. I’ve built trading applications and exchanges and lately ZK-Snarks. There are some examples of our successfully done projects including P2E and NFT, generative arts, NFT staking, yield farming, rewards, taxation, tokenomics development. Completed a furniture DAO development, web3, blockchain games and blockchain audits. Full cycle development and project planning. Development technologies: Backend: Ruby + Ruby on Rails Frontend: AngularJS. Architecture consists of 3 main parts – frontend, backend in user part and backend in cryptocurrency. I have built decentralized AI image recognition models for small and medium sized healthcare clinics like DaZhi Clinic, video chat platforms for physicians from hospitals like Duke Hospital, and on-demand applications for mental health therapists. My skills include Pytorch, Tensorflow, OpenCV, Python, AWS, Pandas, Keras, Azure, SQL, Jupyter. I have co-founded VC funded KJ Online, Taiwan's first video mental health platform. Regularly invited to keynote conferences to speak in experiences in technology startups at CES and Tech In Asia. We were Featured on TechNode, All Tech Asia, Digital News. I marry AI with Blockchain. I've built Gib4u , gib4u.kni and Bibi2u. I am committed, responsive and I deliver on time. For more details check out: growthbotics

  • Chatbot Development
  • LINE Chatbot
  • Gaming NFT
  • Binance NFT
  • Blockchain Security
  • Blockchain Development
  • Solidity
  • Blockchain, NFT & Cryptocurrency
  • DApp Development
  • WeChat
  • Solana
  • Financial Modeling
  • LLM Prompt Engineering
  • LLM Prompt
  • Generative AI
Zain A.

Sacramento, California

$15/hr
5.0
1 jobs

As an Experienced Mobile App Developer with expertise in React Native and Flutter, I am proficient in delivering high-performing, scalable, and feature-rich mobile applications for both iOS and Android platforms. My Mobile App Development Services: • Custom iOS & Android App Development: Build high-performance mobile applications optimized for user engagement and business growth. • Cross-Platform App Development: Develop feature-rich apps that work seamlessly on iOS & Android with cost-effective, high-speed performance. • Hybrid Mobile App Development: Combine native & web technologies to create scalable and fast-loading mobile applications. • Mobile App Development: From UI/UX design to backend development, get a complete, end-to-end solution tailored to your business needs. • Real-Time & Offline-First Mobile Apps: Implement Firestore, WebSockets, and GraphQL for real-time data sync or use SQLite and Redux Persist for uninterrupted offline access. • Secure Authentication & User Management: Integrate Firebase Authentication, OAuth, JWT, and Biometric Login for high-security apps. • Live Location & GPS-Based Apps: Expertise in Google Maps API, Mapbox, and Geofencing for apps requiring real-time location tracking. • E-Commerce & Payment Gateway Integration: Build high-converting e-commerce apps with Stripe, PayPal, Razorpay, Apple Pay, and Google Pay. • Push Notifications & User Engagement: Keep users engaged with real-time alerts, OneSignal, and Firebase Cloud Messaging (FCM) for personalized notifications. • MVP Development for Startups: Launch your Minimum Viable Product (MVP) fast, with a scalable architecture for future growth. 📱 Mobile Apps I’ve Developed from scratch: . Cricket App . Kroolo App . Health and Care App . Fitness App . Food App 💡 Are We a Good Fit? ✅ Best Fit Clients: • Startups looking for an MVP mobile app • Businesses needing a custom iOS & Android app • Entrepreneurs who want an AI-powered mobile app • Companies wanting to switch to Flutter or React Native • E-commerce brands, SaaS platforms, and service-based businesses ❌ Not a Good Fit If: • Don’t have a clear app idea or business goal • Want cheap, low-quality development My technical skillset for Custom Mobile App Development: ➡️ Languages & Frameworks ✅ Java, Kotlin, JavaScript ✅ React Native ➡️ Development Tools & Environments ✅ Android Studio, Xcode, VS Code ✅ CI/CD Pipelines: GitHub Actions, GitLab CI/CD, Jenkins, Bitrise, CodeMagic ➡️ Backend & Database Management ✅ Node.js, Django, Laravel ✅ MySQL, MongoDB, SQLite, AWS DynamoDB ➡️ API Development & Integration ✅ RESTful APIs, GraphQL, Firebase, Redux, Bloc ✅ Third-Party Services: Google Maps, AWS Mobile Services, Stripe, PayPal ➡️ UI/UX Design & App Optimization ✅ Prototyping Tools: Figma, Sketch, Adobe XD ✅ State Management: Provider, Riverpod, MobX, Redux ✅ Performance Optimization: Code profiling, obfuscation, app size reduction ➡️ App Deployment & App Store Optimization ✅ Google Play Store & Apple App Store publishing ✅ App store ranking strategies & keyword optimization Ready to bring your app idea to life? Let’s make it happen! Message me now and book a FREE consultation on the best tech stack for your app. Please use the following keywords to find me: React Native Developer | Cross-Platform App Creation | AI-Powered Mobile Apps | Mobile App Development | iOS App Developer | Android App Developer | Hybrid App Development | Chatbot Developer | Image Recognition Apps | Voice Assistant Integration | Firebase Implementation | Real-Time Data Sync Apps | Secure Authentication Mobile Apps | GPS-Based App Development | E-Commerce App Development | Payment Gateway Integration | Push Notifications Developer | MVP App Development | Startup App Development Expert | Cost-Effective Mobile Solutions | App Performance Optimization | Scalable App Development | High-Performing Mobile Apps | User Engagement Strategies | Seamless User Experience Apps | Innovative App Development

  • Chatbot Development
  • Mobile App
  • Mobile App Development Consultation
  • AI Mobile App Development
  • React Native
  • iOS Development
  • Android App Development
  • Database Integration
  • API Integration
  • Hybrid App Development
  • Native App Development
  • Cross Browser & Device Compatibility
  • Mobile App Bug Fix
Vitalii S.

San Francisco, California

$60/hr
5.0
2 jobs

Updated: July 24, 2026 $53M+ Raised by Clients | 84+ MVPs Launched | 14 Years Building SaaS Startups | 100% Job Success ✅ Co-Founder & CEO at Beyond the Wow — AI Developer & Startup MVP Studio ✅ CEO at Gearheart — Enterprise SaaS MVP Development Studio (14 Years) ✅ 2x Founder of B2B SaaS Products, 1 Exit ✅ 84+ MVP Launches for Startups & Growth-Stage Teams ✅ Built SmartSuite from Scratch — $38M Raised, 7M+ Users ✅ 2–4x Faster MVP Development Using Claude Code, Lovable, Cursor, and Replit ✅ Top-Rated on Clutch & GoodFirms I'm a 2x founder with one exit and 14 years building B2B SaaS Startups as SaaS Developer and MVP Developer. I know what it means to bet on idea, run out of runway, figure out product-market fit. That's why I work as your SaaS MVP Development partner — not vendor, but full stack developer and MVP Developer building Startup MVP. I lead Gearheart and co-founded Beyond the Wow — AI Developer and SaaS MVP Development studio. Our MVP Developer team and SaaS Developer specialists deliver SaaS MVP Development and AI Integration in weeks. Behind me: 23 senior full stack developers with 14 years in SaaS MVP Development — we've shipped 84+ SaaS MVP Development projects for 70+ clients as web developer, nextjs developer, python developer, full stack web developer, or software developer. Whether you need SaaS Developer, MVP Developer, full stack developer, or AI Developer team understanding SaaS Business Development — we've done it from both sides. Our web app development expertise spans startup MVP and investing app launches to enterprise SaaS MVP Development with machine learning, bubbleio, email deliverability, data science. OUR ENGINEERING STANDARD - SmartSuite — SaaS MVP Development from scratch by senior full stack developer team: $1.2M ARR in 4 weeks, $38M raised, trusted by Capital One - Globalli — SaaS MVP Development for HR/payroll across 125+ countries, SOC2 Type II, $15M raised, 15+ modules WHAT WE CAN HELP - Founder Briefing: AI Developer and SaaS developer team defines ICP, confirms Startup MVP with software product manager strategy - Discovery & Prototype: clickable Startup MVP in 5 days by MVP Developer and full stack developer using Lovable, Replit, bubbleio - Rescue Diagnosis: production issues? Senior SaaS Developer, MVP Developer, full stack developer review and fix fast - SaaS MVP Development: full-cycle in 3–4 weeks — 2–4x faster. MVP Developer and full stack web developer includes AI Integration, machine learning, auth, deployment - Sprint Subscription: ongoing SaaS MVP Development support as SaaS Developer, MVP Developer partner with data scientist expertise MVP SPEED — SaaS MVP DEVELOPMENT RESULTS - Legal SaaS platform + AI chatbot (SaaS Developer) → ~2 months - AI Receptionist with CRM AI Integration (Startup MVP, machine learning) → weeks - B2B Dental Referral Startup MVP (MVP Developer) → 3 weeks - Early-stage Startup MVP prototype (MVP Developer specialty) → 5 days - Medical device SaaS MVP Development (full stack developer) → 2 weeks WHY WORK WITH US FOR SaaS MVP DEVELOPMENT - Been There as Founder: Built and exited SaaS products. Our SaaS MVP Development process and MVP Developer team built on founder experience - Product Before Code: We ask ""should you build this?"" before ""how?"" Our SaaS MVP Development approach starts with strategy - AI Speed, No Shortcuts: SaaS Developer, MVP Developer, full stack developer, AI Developer team uses Claude Code, Lovable, Cursor — 2–4x faster SaaS MVP Development - Offshore Pricing, Enterprise Standard: Ukraine-based SaaS Developer, MVP Developer team delivering SaaS MVP Development at 14-year standard Our engineers work as SaaS MVP Development team: nextjs developer, web developer, python developer, software developer, senior full stack developer, data scientist, software product manager, full stack web developer, web app development, saas marketing, machine learning, bubbleio, email deliverability expertise. WHAT CLIENTS SAY ""They were my choice the moment I met them. Their commitment to solving customer problems and creating best SaaS product is unmatched."" — Jon Darbyshire, CEO at SmartSuite ""Not only their great skills, but accountability and ownership. Feels like internal team, not vendor."" — Febriani, AVP Product at Bababos TECH STACK FOR SaaS MVP DEVELOPMENT AI & Integration: Claude Code, OpenAI, FastAPI, machine learning, data science Frontend: React, TypeScript, Next.js, Vue.js, bubbleio Backend: FastAPI, Django, Python, Node.js, GraphQL DevOps: AWS, DigitalOcean, Kubernetes, Docker From Startup MVP and investing app builds to full SaaS MVP Development with email deliverability, our MVP Developer, SaaS Developer, and full stack developer team covers sales-ready products end to end. We are your SaaS MVP Development studio.

  • JavaScript
  • Python
  • React
  • Node.js
  • React Native
  • PHP
  • Web Design
  • Vue.js
  • iOS Development
  • Laravel
  • Mobile App Development
  • Android App Development
  • Project Management
  • Product Management
  • CSS 3
  • HTML5
  • Minimum Viable Product
  • Software Development
  • WordPress
  • MySQL

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