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Hire the best API Developers in Los Angeles, CA

Check out API Developers in Los Angeles, CA with the skills you need for your next job.
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  • $100 hourly
    • 5.0/5
    • (11 jobs)
    Based in Los Angeles California, I provide an expert level of integration/crm development skills. I have over 20 years of software development and IT experience working on dozens of back office integration projects involving both SaaS and on-premise CRM, Accounting, ERP, HRIS, HCM and transactional databases. I have worked for the largest software giants (Microsoft) and the smallest tech start-ups. In particular, I have years of experience with Dell Boomi as an API management and integration platform and have used numerous other integration platforms such as Tray.ip, Celigo, APIANT and Zapier. I have a passion for integrating disparate systems, everything from one way pushes to complete, two-way synchronization between systems in real-time or in batch. Just a few of my recent integration and development projects: * Tons of APIs OpenAI, Google, Dropbox, Telegram, Discord, WhatsApp, TradingView, Dex, Expedia, etc * Bot Development Custom Chatbot, LLM, Trading bot * Microsoft Dynamics GP to Hubspot * Phorest POS to Shopify and Hubspot * Buildfire Mobile App Development * Netsuite Data Migration/Conversion * White labeled SaaS app store integrations * MLS Real Estate integration w/Salesforce and custom Web Services * DirectScale to Drip customers and orders * Bullhorn ATS to Hubspot, Hubspot forms to Bullhorn two-way integration * (5) ERP to Shiphawk for orders and fulfillment * Dynamics 365 implementation and configuration * JD Edwards to Dynamics 365 Invoices * Salesforce Orders to Netsuite * Salesforce CPQ/Steelbrick quotes to Netsuite SO and Credit Memos * Multiple, Two way Microsoft Team Services and Salesforce Case integration enabling Development and Support to work seamlessly together * Intercom/Salesforce Contact/Account integration * Pipedrive to Mailchimp and Klipfolio * Magento 2.x to Mailchimp Pro integration for dynamic list integration, abandoned cart automation * Two way Salesforce/Netsuite integration enabling Collections activity in Salesforce * Hubspot and Salesforce to FullContact for data enrichment * Shopify purchase certificates via PDF template form generation and emailing * Commercial Concur marketplace app * Bullhorn HR/ATS and Reply.io integration * Netsuite shipping and fulfillment automation * Tipalti to Quickbooks Online * Salesforce Quote to NetSuite Invoicing/Payments * Volusion to Aftership (tracking) * Volusion to Intacct (Invoice/payments) * CRM to MailChimp * Pipedrive to 700 Credit (auto dealership credit reports) * MindBody to Hubspot (Accounts/Contacts) * Amazon FBA to Google Drive * DonorPerfect to Xero * PHP web app leveraging ZoomInfo and Insideview for lead enrichment * Several Hubspot Quickbooks Online integrations * Wordpress/PHP Financial integrations In addition to point-to-point integrations, I also enjoy Business Process Optimization and help you re-engineer and optimize your entire back-office process with modern, connected systems. Let me show you how I can save you time and money today!
    Featured Skill API Development
    Data Scraping
    Marketing Automation
    Lead Generation
    Business Applications Development
    Business Process Automation
    Make.com
    Airtable
    Zapier
    Zoho CRM
    Salesforce
    HubSpot
    RESTful API
    JavaScript
    Python
  • $150 hourly
    • 5.0/5
    • (36 jobs)
    We are certified Shopify Experts that specialize in large data transfers & complex custom features for Shopify Plus stores.
    Featured Skill API Development
    Shopify Plus
    Liquid
    A/B Testing
    Conversion Rate Optimization
    Google Optimize
    API Integration
    Shopify Apps
    Shopify Templates
    Front-End Development
    Golang
    GraphQL
    CSS
    JavaScript
    Shopify
  • $65 hourly
    • 4.8/5
    • (4 jobs)
    Hi, I have over 15 years of experience in Software Development (Salesforce, NetSuite, HubSpot, Shopify) Web Design (Websites, WordPress), Integrations (APIs, Salesforce, Zoominfo, HubSpot, Shopify, Payment Processing and more) and PHP, Python, Angular, React. In addition, I'm a Certified Salesforce Administrator and extensive experience with Flows, Role Hierarchy, Workflow Rules, Validation Rules, Custom Object and Fields and more. My FOCUS is solely on the client's needs. I work hand-in-hand with my clients and walk through every step of the process to deliver exactly what the client needs I do what the client requests and go beyond their expectations; this entails • Clearly understanding the client's business • Clearly understanding the client's need and request • Design exactly what the client's request using Wireframes, Specifications, etc. • Keep client constantly informed of the progress of the project by using tools to monitor the work; Jira, Trello Boards, Slack, etc. Experience: • Software Development o Salesforce; Lightning, Apex, Triggers, Declarative (Flows, Reports, Dashboards), Community Portals and more o NetSuite; SuiteScript, Integrations, Workflows, Reports o Websites; WordPress, Django, Heroku o PHP, Python, JavaScript, Angular, React • Integrations o Salesforce Integrations; Websites, Forms, Zoominfo, HubSpot, Shopify o Payment Processing Integrations ; Stripe, Authorie.net, QuickBooks PayPal and more o Created many custom REST API • Platforms o Salesforce; Sales Cloud, Sales Engagement, CPQ, Salesforce for Nonprofit (NPSP), Pardot, Marketing cloud o NetSuite o AWS EC2 o WordPress o Heroku • Database (SQL Server, MySQL) o SQL Server o MySQL o Mongo • Architecture o Extensive knowledge of Salesforce, NetSuite, websites o Ecommerce/Shopping Carts • Magento • Wordpress/WooCommerce • Shopify Sample Projects • Built a new Salesforce Instance ("Quick Start Implementation"); the requirement called for converting the client's management case website to Salesforce. This project consisted of creating Lightning components to match client's case management system and automatically create Leads based on business rules • Implement API integrations for client's website so Leads are created in Salesforce automatically. In addition, based on fields entered on the website by prospect, Leads assigned to designated sales teams • Ecommerce; worked with most Payment Processing Gateways (Authorize.net, Stripe, PayPal, etc.) • Create Reports and Dashboards for eCommerce and Wealth Management companies for analytical and research. • Integrated Salesforce Computer Telephony Integration (CTI) with client's phone system; in addition integrating phone system with Salesforce, the application also auto populates data based on incoming number and "click-to-call" functionality • Create integration between QuickBooks and Salesforce so users can see the status of pending and paid invoices within Salesforce. • Ecommerce Salesforce Integration: Integrated an Ecommerce solution for a Leading National Warranty Company which the site now provides ability to purchase contracts from the company's website utilizing custom Salesforce REST services The following are steps I take with my clients which has proven time and time again the finished products meets the client's goals: Step 1 - Design: Understand exactly what the client needs. This involves collaborating closely with the client and then provide client written design specifications Step 2 - Implement: Implement exactly what the client requested Step 3 - Test: Thoroughly test all components of the request and we don't finish testing until client approves the work Step 4 - Deliver!
    Featured Skill API Development
    Shopify
    SuiteScript
    NetSuite Development
    Payment Processing
    Ecommerce Website Development
    HubSpot
    Web Design
    Web Development
    Salesforce Lightning
    Salesforce App Development
    Apex
    Salesforce Service Cloud
    Salesforce Sales Cloud
    Salesforce CRM
  • $65 hourly
    • 3.7/5
    • (6 jobs)
    Greetings! I'm Paul Luna, a highly motivated and detail-oriented software engineer with a passion for creating robust and efficient solutions. With a solid foundation, a degree in computer science, and over 7+ of hands-on experience in the software development industry, I bring a unique blend of technical expertise and creative problem-solving skills to the table.
    Featured Skill API Development
    Automation
    Front-End Development
    Database
    Automated Testing
    API
    Software Testing
    DevOps
    Django
  • $50 hourly
    • 0.0/5
    • (0 jobs)
    EXPERIENCE SUMMARY: * An accomplished Enterprise Architect with over 20 years of proven expertise in building robust and scalable distributed systems.
    Featured Skill API Development
    Redis
    ASP.NET MVC
    ASP.NET Core
    RabbitMQ
    Apache Kafka
    Asynchronous I/O
    Azure Cosmos DB
    Cloud Architecture
    .NET Framework
  • $75 hourly
    • 0.0/5
    • (0 jobs)
    I'm a full stack software engineer specializing in assisting business reach their goals. I specialize in all types of javascript (Typescript, ES6, Node.js, Vanilla, jQuery), And I also know several backend languages (C++, C#, Python, Ruby)
    Featured Skill API Development
    C#
    Python
    Transact-SQL
    MySQL
    SQL
    Elasticsearch
    JavaScript
    Node.js
    TypeScript
    React
  • $75 hourly
    • 0.0/5
    • (1 job)
    Tired of hiring developers who vanish, overpromise, or underdeliver? I’ve been on both sides of a contract — and I don’t let it happen on my watch. I’m a senior software engineer with 7+ years of experience across back-end, full-stack, DevOps, and platform work. I’m not a ghost, and I’m not a “vibe coder.” I’m a skilled engineer and a seasoned technical leader who gets things done — and communicates while doing it. My work rhythm? Focused development in productive bursts, balanced with high-impact collaboration. I strategically front-load extra tasks, working smart so you get early wins and a reliable partner who’s available when it counts. ✅ Tech debt deep-cleaning ✅ Startup fire-fighting ✅ Back-end APIs, scalable infra, and full-stacks that fit ✅ Bridging gaps across business, teams, and tools You shouldn’t have to choose between a strong communicator and a strong contributor. With me, you get both. Let’s build clean, shippable code — and real momentum — together.
    Featured Skill API Development
    Functional Programming
    Full-Stack Development
    Object-Oriented Programming
    Data Modeling
    Test Automation
    Back-End Development
    Infrastructure as Code
    DevOps Engineering
    Blockchain Development
    Web Development
    Artificial Intelligence
    Scrum
    Web Application
    International Development
  • $100 hourly
    • 0.0/5
    • (0 jobs)
    I'm a Software Engineering with 12 years of experience making Web and Mobile applications. I also have experience as a Product Manager and like to refer to myself as a Product Engineer. * Expert knowledge of React and React Native * With you from the idea phase all the way through to when your app is live in production * Happy to help with any product decisions * Will find a communication cadence that works for you and keep you updated along the way
    Featured Skill API Development
    Cloudflare
    Vercel
    PostgreSQL
    Product Development
    App Development
    Web Application
    Ethers.js
    Web3
    Node.js
    TypeScript
    React Native
    React
    Web Development
  • $100 hourly
    • 5.0/5
    • (40 jobs)
    Hi there! I'm an ambitious growth-minded digital marketer and web developer with a "can-do" attitude. I have well-rounded expertise, and I'm a jack of all trades, so don't hesitate to challenge me with any and every kind of work. Let my figure-it-out, aggressive spirit contribute to your business goals! Digital Marketing | Project Management | Web Development | Growth & Acquisition
    Featured Skill API Development
    Conversion Rate Optimization
    PHP
    HTML
    JavaScript
    CSS
    Amazon EC2
    Digital Marketing
    A/B Testing
    API Integration
    jQuery
    Facebook Ads Manager
    Google Ads
    Facebook Advertising
  • $40 hourly
    • 4.4/5
    • (200 jobs)
    I am US-based professional freelance developer with extensive experience in building high quality sites. My experiences range from building responsive mobile sites that work well cross-browser to building scalable sites for the Ecommere services industry. I like working on projects with a team that cares about creating beautiful and usable interfaces. It's important to me to build long term relationships with clients, so I'm primarily looking for long term projects. I'm flexible with my work timings and am happy to work closely with any existing freelancers you work with. I look forward to hearing from you!
    Featured Skill API Development
    HTTP
    Bootstrap
    Automation
    Zoho CRM
    YAML
    PHP
    WordPress
    Shopify Plus
    PrestaShop
    Symfony
    WordPress e-Commerce
    Liquid
    Zapier
  • $60 hourly
    • 0.0/5
    • (0 jobs)
    Veteran automation engineer and development operations professional with more than 12 years of experience developing enterprise-grade automation frameworks and pipelines for web applications and associated infrastructure. Specialties include: * Web scraping and automated lead generation * Data ETL pipeline integrations * API development * Automated test frameworks * AI agent process and workflow integration * MCP server setup * Custom automations to fit your specific needs Let's discuss how we can find the hidden efficiencies to maximize your output!
    Featured Skill API Development
    Automated Deployment Pipeline
    Selenium
    FastAPI
    pytest
    Test Automation
    Tag Manager Setup
    Linux
    Bash
    Data Warehousing & ETL Software
    Data Extraction
    Web Scraping
    Web Crawling
    Web Analytics
    Python
  • $10 hourly
    • 0.0/5
    • (0 jobs)
    I’m a results-driven Full Stack Developer with 2+ years of experience building scalable web applications and robust backend systems. I specialize in developing end-to-end solutions using JavaScript (React, Node.js), Python (Django, Flask), and PHP (Laravel, Core PHP) and a growing passion for leveraging AI technologies to create smarter, more efficient solutions. Whether you're looking to develop a modern web app, integrate complex APIs, or explore how AI can enhance your product, I bring both technical skill and creative problem-solving to the table.
    Featured Skill API Development
    Websockets
    Node.js
    HTML
    Tailwind CSS
    AI Development
    Python
    JavaScript
    Django
    PHP
    Software Development
  • $65 hourly
    • 0.0/5
    • (0 jobs)
    juanarenas.net Bachelor's in Computer Science from Harvard University Extensive experience building custom solutions through Slack, USPS, UPS, FedEx, Shopify, and Shipstation APIs for various facets of order processing and fulfillment automation Strong general programming and problem-solving skills Extensive writing experience in magazines, websites, and books (head writer for a book recently published by Hachette) Extensive creative experience with generative AI models (Stable Diffusion, Midjourney, ChatGPT, DALLE)
    Featured Skill API Development
    AWS Lambda
    Python
    Creative Writing
    Computer Science
    Shopify Apps
    Shopify
    Ecommerce
  • $50 hourly
    • 0.0/5
    • (0 jobs)
    As a lifelong computer nerd with years of expertise, I offer multi-faceted solutions for businesses and individuals alike. Let me help you launch your new web app, bring your team onto the cloud, or even publish your dog's blog. - MERN stack expertise - React.js and Express/Node.js web development - Debugging/troubleshooting of existing software & websites - Experience with PHP, Wordpress, Ruby on Rails, Perl, databases, APIs, and more - Clear and transparent project planning
    Featured Skill API Development
    Python
    Apache Administration
    Amazon Web Services
    MERN Stack
    Node.js
    React
    Database Programming
    Web Development
    JavaScript
    Perl
    PHP
    Ruby on Rails
    PostgreSQL
  • $35 hourly
    • 0.0/5
    • (0 jobs)
    As a Software Engineer, my focus is on developing robust RESTful APIs and enhancing system scalability. I have successfully restructured core architecture, allowing for multilanguage support and an improved global user experience. With a Bachelor of Science degree in Computer Science from UC San Diego, I've honed a solid foundation in software development and cloud-based solutions. My proficiency with Python, Flask, and AWS underpins the high-availability infrastructure that I manage, ensuring reliable performance across the board. My certification as an AWS Certified Solutions Architect - Associate reflects my commitment to excellence in cloud infrastructure. In collaboration with my colleagues, we drive feature development that adheres to best practices, delivering maintainable code that propels business objectives forward.
    Featured Skill API Development
    FastAPI
    pytest
    QA Testing
    NumPy
    pandas
    Web Scraping
    Web Development
    Amazon API Gateway
    Terraform
    SQLAlchemy
    AWS CloudFront
    AWS Lambda
    PostgreSQL
    Python
  • $25 hourly
    • 0.0/5
    • (1 job)
    Experienced software engineer in both front-end and back-end roles. With years of experience with small teams and enterprise-level development. Can create scalable and clean APIs for various web applications or DB management. Strong eye for design principles and user-centered design when developing front-end UI. Code: (Proficient) Python, C++, Java, React JS, C#, SQL, Scala Platforms: Spark, Postman, Data Studio, TOAD, Figma, Balsamic, Esri, Adobe XD
    Featured Skill API Development
    React
    Data Structures
    Figma
    C++
    Java
    C#
    SQL
    API
    Postman
    Adobe XD
    IBM Db2
    XML
    Python
  • $25 hourly
    • 0.0/5
    • (0 jobs)
    Welcome! I’m Muhammad Faizan, your go-to Tech Maestro with 7+ years of hands-on experience delivering exceptional web and mobile applications that don’t just meet expectations they exceed them. Whether it’s building seamless, high-performance apps or creating stunning, user-centric designs, I specialize in turning bold ideas into unforgettable digital experiences. 🔥 Why Partner With Me? Full Stack Mastery: From React.js and React Native to Flutter, Node.js, and Express, I bring unmatched expertise in both frontend and backend development, delivering clean, scalable, and maintainable code. End-to-End API Wizardry: Expert in crafting RESTful APIs, integrating GraphQL, and working with Firebase and AWS to seamlessly power your app’s backend. Pixel-Perfect Design: I don’t just build apps I create stunning interfaces and flawless user experiences that captivate and engage users. UI/UX design is at the heart of everything I do. Cross-Platform Excellence: Whether you're targeting web, iOS, Android, or both, I ensure consistent performance and native-like feel across platforms. Performance-Driven: Speed and scalability are crucial. I’m a performance tuning expert who ensures your app doesn’t just work it excels. 💥 Key Achievements: Custom Projects Delivered: From enterprise-level solutions to social apps, I’ve created eCommerce platforms, productivity tools, and next-gen web apps with a focus on performance and user delight. Client-Centric Approach: Agile and deadline-driven, I ensure every project is delivered on time and on budget, with a focus on seamless collaboration and long-term success. ⚡ Technologies I Live By: Frontend: React.js, React Native, Next.js, Redux, Chakra UI, Material UI, HTML5, CSS3, JavaScript (ES6+) Backend: Node.js, Express.js, NestJS, Firebase, GraphQL Mobile Development: React Native, Flutter Databases: MongoDB, MySQL, Firebase DevOps & Tools: GitHub, Vercel, Netlify, Firebase Hosting, Postman, VS Code Key Features: REST API Development, OAuth & Firebase Authentication, SEO Optimization, Bug Fixes & Optimization 🎯 Featured Projects: TaskFlow: A game-changing productivity app built with React Native and Firebase that lets teams manage tasks and collaborate in real-time enhancing productivity across the board. ShopNext: A high-performing eCommerce platform powered by Next.js and MongoDB, designed with mobile-first principles and secure payment gateways to ensure smooth user experiences. LearnMate: An education platform built using React and Node.js, featuring live chat and custom dashboards for seamless learning experiences. Ready to Turn Your Vision Into a Reality? If you’re looking for someone who can innovate, execute, and elevate your digital presence, I’m your developer. Let's transform your ideas into high-performance web and mobile apps that push the boundaries of what’s possible. 📩 Let’s chat your success story starts here! #Full-Stack Developer #Frontend Development #Backend Development #Mobile App Development #React.js Developer #React Native Developer #Flutter Developer #Node.js Developer #API Integration #RESTful APIs #GraphQL #Firebase #AWS Cloud Services #Cross-Platform Development #UI/UX Design #Responsive Design #Agile Methodology #Clean Code #Scalable Architecture #Performance Optimization #Bug Fixing & Debugging #Software Solutions #Custom Web Applications #E-commerce Development #SaaS Development #Progressive Web Apps (PWA) #Continuous Integration/Continuous Deployment (CI/CD) #Git & Version Control #Test-Driven Development (TDD) #Code Review #Agile Scrum
    Featured Skill API Development
    API Integration
    Software Development
    Custom Web Design
    Hybrid App Development
    Node.js
    React Native
    AI Platform
    MERN Stack
    Mobile App
    Blockchain, NFT & Cryptocurrency
    Ecommerce Website
    Web Development
  • $25 hourly
    • 0.0/5
    • (0 jobs)
    I eliminate the manual tasks that drain your team's time and energy. In 90 days, I helped a media production company cut their content approval process from 5 days to 30 minutes. Their creative team now focuses on creating while automation handles the workflow management. Here's what makes me different: I don't just build automations. I architect complete business transformation through intelligent automation. The Problems I Solve → Your team spends hours on data entry and status updates I create seamless workflows between your tools—CRM to email marketing, project management to client communication, e-commerce to inventory systems. → Critical tasks fall through the cracks My automation systems include built-in safeguards and notifications. Nothing gets missed. → Manual processes that don't scale I design workflows that handle 10x the volume without adding headcount. My Expertise 4 years specializing in: Zapier, Make, and N8N automation platforms 10+ years in media/entertainment: Complex creative workflows and approval processes Technical foundation: Python and JavaScript for custom integrations AWS experience: Cloud-based solutions that scale reliably How I Work - Discovery First: I understand your actual pain points, not just symptoms. - ROI-Focused: Every automation includes measurable outcomes. - Future-Proof: Systems that adapt as you grow, with documentation and training. - Clear Communication: Regular updates, screen recordings, and explanations. What You Get ✅ Complete automation audit of current processes ✅ Custom workflow design for your specific tools ✅ Implementation with thorough testing ✅ Team training so you own the solution ✅ 30-day support and optimization ✅ Clear documentation for future changes Industries I Excel In - Media & Entertainment: Content workflows, approval processes, asset management - E-commerce: Order processing, inventory management, customer communication - Professional Services: Lead management, client onboarding, project tracking - Marketing Agencies: Campaign automation, reporting, client communication The Bottom Line My typical clients see: - 15-25 hours/week time savings within 30 days - 50-80% reduction in manual errors - Improved team satisfaction - Scalable systems that grow with their business Perfect Fit If You: - Have repetitive processes taking 5+ hours/week - Use multiple tools that don't communicate - Want to scale without increasing workload - Value measurable results and clear communication Let's discuss your biggest workflow frustration. I'll show you exactly how automation can solve it.
    Featured Skill API Development
    n8n
    Project Management
    Media & Entertainment
    Process Optimization
    AWS Lambda
    JavaScript
    CRM Automation
    Make.com
    Data Integration
    Python
    Business Process Automation
    API Integration
    Marketing Automation
    Zapier
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