Hire the Best System Programmers in California

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Bill A.

Los Angeles, California

$70/hr
5.0
4 jobs

Senior Business Analyst, Developer, Database Designer, and Software Architect with a proven record of delivering effective results for complex business problems. Master of business/IT collaboration, object-oriented software development, and problem solving. Conference speaker, author and data dog.

  • Microsoft SQL Server
  • Database Design
  • Visual FoxPro
  • FoxPro Programming
  • Software Architecture
  • Data Modeling
  • Business Analysis
  • Object-Oriented Design
Sanjay S.

Cupertino, California

$95/hr
4.9
285 jobs

I have experience in building custom software solutions tailor-made to your requirements. My skill-set spans multiple domains like financial, healthcare, eCommerce, advertising, education, life sciences, hotel/hospitality, media and entertainment, retail, real estate, sports and fitness, mobile and wireless, technology, non-profit and more industries. I use structured programming incorporating leading & tested frameworks, best programming practices, coding guidelines and standards. As the technology advances gradually and the programming landscape changes globally, inorder to accommodate the world's growing technological needs, I constantly evaluate the latest trends in the development community and try to constantly improve and upgrade my skills to provide my clients the best possible development solutions.

  • .NET Framework
  • PHP
  • Database
  • Python
  • React
  • Angular
  • AJAX
  • ChatGPT
  • Google Cloud Platform
  • Facebook Development
  • Google Map Maker
  • Linux System Administration
  • Moodle
  • OAuth
  • Open Source
Mike K.

Yorba Linda, California

$56/hr
5.0
21 jobs

Hey there, I'm Mike! I specialize in turning business ideas into production-ready web applications fast! Whether you need a high-converting landing page, a full e-commerce platform, or backend automation to eliminate manual workflows, I deliver enterprise-grade solutions at startup-friendly prices. My focus is fixed-price projects with clear scopes and timelines, so you know exactly what you're getting and what you'll pay before we start. With 20+ years of software engineering experience across advertising, gaming, financial services, and e-commerce, I've built systems that process millions of transactions and serve millions of users. Currently, I'm a Sr. Manager of Engineering at a major e-commerce brand, leading teams that ship production code daily. I bring that same level of quality and reliability to every freelance project without the agency overhead or enterprise price tag. When you hire me, you get me! I don't outsource my work; I do it all myself. My sweet spot is helping businesses launch MVPs, automate repetitive tasks, and build scalable web platforms in days, not months. I use modern, proven technologies (NextJS, Supabase, n8n) that give you speed to market, easy maintenance, and room to grow. Most projects deliver in 1-2 weeks with source code in GitHub, documentation, and deployment included. What I Deliver: ✅ NextJS websites – Landing pages, e-commerce sites, web apps with server-side rendering ✅ n8n automation workflows – Email sequences, Slack notifications, CRM integrations, data pipelines ✅ Supabase backend – PostgreSQL databases, user authentication, REST APIs, real-time features ✅ Mobile-responsive design – TailwindCSS, pixel-perfect on all devices ✅ Clerk OAuth – Customers can login with Google, Apple, and Social credentials ✅ Stripe payment integration – One-time payments, subscriptions, checkout flows ✅ Fast delivery – 1-2 week turnaround on most projects, with clear milestones Tech Stack: NextJS, React, TypeScript, Supabase, Clerk, Drizzle ORM, TailwindCSS, Stripe, n8n, PostgreSQL My Approach: Fixed-price projects mean no surprises. You get a detailed scope, timeline, and price upfront. I build, you review, we launch. Source code is yours, deployments are documented, and you're never locked into proprietary systems. Let’s make some magic together!

  • Web Application
  • Web Development
  • App Development
  • Next.js
  • React
  • Supabase
  • JavaScript
  • WordPress
  • Shopify
  • Netlify
  • Vercel
  • PHP
  • HTML
  • CSS
  • Tailwind CSS
Umair A.

Fremont, California

$55/hr
4.8
54 jobs

I build production-ready AI agents that automate customer support, operations, CRM workflows, document processing, and internal business processes using OpenAI, Claude, LangGraph, n8n, MCP, and Python. With 10+ years of experience delivering production-ready software solutions, I help startups, agencies, and growing businesses connect AI, automation, data, and business processes into systems that create measurable impact. Whether you're launching a SaaS product, automating operations, implementing AI-powered workflows, or building internal business tools, I focus on delivering scalable, maintainable solutions that teams actually use. AI Automation & Workflow Systems I design and implement intelligent automation solutions that reduce manual effort, streamline operations, and improve decision making. • AI Agents & Conversational AI • OpenAI, Claude, Gemini & LLM Integrations • Agentic Workflows & Multi-Agent Systems • RAG & Knowledge-Based Systems • AI-Powered Business Workflows • AI Outreach & Follow-Up Automation • Workflow Orchestration with n8n, GoHighLevel (GHL), Zapier & Make • Human-in-the-Loop Automation Systems • AI Decision & Recommendation Engines • Internal AI Tools & Productivity Systems • MCP (Model Context Protocol) Integrations CRM & Revenue Operations Automation I build CRM ecosystems and revenue operations infrastructure that help businesses manage leads, automate sales processes, and improve visibility across their customer journey. • HubSpot & GoHighLevel (GHL) CRM Automation • Sales Pipeline Automation • Lead Scoring & Segmentation • RevOps & GTM Systems • Outreach Infrastructure & Follow-Up Automation • CRM Integrations & Data Synchronization • Operational Dashboards & Reporting • Email Automation & Deliverability Systems • Google Workspace Automation & Apps Script • API Integrations Across Business Platforms SaaS MVP & Product Development I help founders transform ideas into scalable products without unnecessary complexity. • SaaS Product Development • Multi-Tenant SaaS Platforms • Marketplace & Booking Platforms • AI-Powered SaaS Applications • Mobile Apps with React Native & Flutter • Internal Business Tools • Admin Dashboards & Portals • Messaging & Notification Systems • Payment & Subscription Integrations • User Management & Authentication • MVP Architecture & Product Scaling Full Stack Engineering • Python, FastAPI, Django, Flask • Node.js, Express.js • React.js, Next.js, TypeScript • PostgreSQL, MySQL, MongoDB, Redis • Supabase & Backend Services • AWS, Docker, CI/CD • REST APIs & Third-Party Integrations • System Architecture & Performance Optimization Business-Focused Results I focus on building systems that: • Reduce manual work and operational bottlenecks • Improve sales, customer, and business workflows • Centralize business data and reporting • Automate repetitive processes at scale • Increase team productivity and efficiency • Support long-term growth and scalability • Deliver measurable operational impact If you need AI-powered workflows, CRM automation, GoHighLevel implementation, AI agents, SaaS development, operational dashboards, custom integrations, or internal business tools, I can help design and build solutions tailored to your business goals. 𝐋𝐞𝐭’𝐬 𝐛𝐮𝐢𝐥𝐝 𝐬𝐲𝐬𝐭𝐞𝐦𝐬 𝐭𝐡𝐚𝐭 𝐬𝐚𝐯𝐞 𝐭𝐢𝐦𝐞, 𝐢𝐦𝐩𝐫𝐨𝐯𝐞 𝐨𝐩𝐞𝐫𝐚𝐭𝐢𝐨𝐧𝐬, 𝐚𝐧𝐝 𝐡𝐞𝐥𝐩 𝐲𝐨𝐮𝐫 𝐛𝐮𝐬𝐢𝐧𝐞𝐬𝐬 𝐬𝐜𝐚𝐥𝐞.

  • Python
  • AI App Development
  • AI Agent Development
  • n8n
  • FastAPI
  • OpenAI API
  • Automation
  • Machine Learning
  • Generative AI
  • AI Chatbot
  • OpenAPI
Gayithri P.

San Jose, California

$60/hr
5.0
2 jobs

𝗥𝗲𝗹𝗶𝗮𝗯𝗹𝗲 𝗔𝗜 𝗱𝗼𝗲𝘀𝗻'𝘁 𝗰𝗼𝗺𝗲 𝗷𝘂𝘀𝘁 𝗳𝗿𝗼𝗺 𝗯𝗲𝘁𝘁𝗲𝗿 𝗽𝗿𝗼𝗺𝗽𝘁𝘀. 𝗜𝘁 𝗰𝗼𝗺𝗲𝘀 𝗳𝗿𝗼𝗺 𝗯𝗲𝘁𝘁𝗲𝗿 𝗲𝗻𝗴𝗶𝗻𝗲𝗲𝗿𝗶𝗻𝗴. 𝗜 𝗯𝘂𝗶𝗹𝗱 𝗔𝗜 𝘁𝗵𝗮𝘁 𝗲𝗮𝗿𝗻𝘀 𝗶𝘁𝘀 𝘄𝗮𝘆 𝗶𝗻𝘁𝗼 𝗽𝗿𝗼𝗱𝘂𝗰𝘁𝗶𝗼𝗻. First call is free — no pitch, just a conversation about what you need. I spent 5 years as a backend engineer at Walmart, Oracle, and VMware, building systems where reliability wasn't optional. Now I apply that same engineering discipline to AI — because the gap between a promising demo and a product your customers can depend on is almost always engineering work, not model work. Datalumina-certified AI Engineer, focused on production-ready RAG, LLM orchestration, and evaluation. I write about RAG, LLM evaluation, and production AI engineering — happy to share case studies and technical posts on our first call. ✦ 𝗪𝗵𝗮𝘁 𝗜 𝗯𝘂𝗶𝗹𝗱 • RAG assistants that cite their sources and gracefully say "I don't know" • Support chatbots grounded in your docs and ticket history — ones that actually resolve • Internal AI tools wired into your CRM, database, or Notion — the kind your team keeps using after week one • Python-based workflow automation that quietly runs the work no one wants to do manually ✦ 𝗛𝗼𝘄 𝗜 𝘁𝗵𝗶𝗻𝗸 𝗮𝗯𝗼𝘂𝘁 𝗔𝗜 𝘄𝗼𝗿𝗸 • Retrieval and cost-optimization first, model second. • I evaluate before I promise — if I can't measure it, I won't claim it won't break • Guardrails from day one — not bolted on after the first embarrassing output • I match the tool to the problem — sometimes a scheduled script beats an AI agent, and I'll tell you when that's true ✦ 𝗧𝗼𝗼𝗹𝘀 𝗜 𝘄𝗼𝗿𝗸 𝘄𝗶𝘁𝗵 𝗟𝗮𝗻𝗴𝘂𝗮𝗴𝗲𝘀 • Python • SQL 𝗕𝗮𝗰𝗸𝗲𝗻𝗱 • FastAPI • PostgreSQL • Redis queues 𝗔𝗜 / 𝗠𝗟 • OpenAI • Claude • Gemini • PydanticAI • LangChain 𝗥𝗲𝘁𝗿𝗶𝗲𝘃𝗮𝗹 • PostgreSQL with pgvector and TimescaleDB • Semantic search, Hybrid search 𝗔𝘂𝘁𝗼𝗺𝗮𝘁𝗶𝗼𝗻 • Python • Scheduled jobs 𝗜𝗻𝗳𝗿𝗮𝘀𝘁𝗿𝘂𝗰𝘁𝘂𝗿𝗲 • Hetzner Cloud • AWS • Docker • Git ✦ 𝗛𝗼𝘄 𝘄𝗲'𝗹𝗹 𝘄𝗼𝗿𝗸 𝘁𝗼𝗴𝗲𝘁𝗵𝗲𝗿 • Our first call is free — we figure out what "done" looks like before I quote • I write down scope, tests, and acceptance criteria, so you always know where we stand • You'll get readable code, short docs, and a working demo — never a black box • I don't disappear at handoff — I'll help you through deployment and the first round of real-world fixes Tell me what you're trying to solve. I'll ask the right questions before quoting anything.

  • Artificial Intelligence
  • Python
  • Retrieval Augmented Generation
  • LangChain
  • Vector Database
  • LLM Prompt
  • Docker
  • Git
  • Java
  • REST API
  • Spring Boot
Numan U.

Sacramento, California

$40/hr
4.8
69 jobs

𝗧𝗼𝗽 𝗥𝗮𝘁𝗲𝗱 𝗣𝗹𝘂𝘀 | 𝟭𝟬𝟬% 𝗝𝗼𝗯 𝗦𝘂𝗰𝗰𝗲𝘀𝘀 | 𝟭𝟯+ 𝗬𝗲𝗮𝗿𝘀 | 𝟴,𝟬𝟬𝟬+ 𝗨𝗽𝘄𝗼𝗿𝗸 𝗛𝗼𝘂𝗿𝘀 | $𝟮𝟬𝟬𝗞+ 𝗘𝗮𝗿𝗻𝗲𝗱 | I'm a senior .NET / C# developer and Azure cloud architect who builds and scales production systems for companies that can't afford downtime or rework — healthcare platforms, fintech products, e-commerce systems, and real estate/property-management software. If your project needs more than someone who writes code to spec — if you need someone who can architect the solution, own the delivery, and still be there for support six months later — that's the role I take on. WHAT I BUILD ──────────────────────── ✦ SaaS Platforms — multi-tenant, subscription-based .NET Core / Azure applications built to scale from a handful of users to enterprise volume ✦ Healthcare Systems — HIPAA-aware EHR/EMR platforms, HL7/FHIR integrations, and clinical workflow tools built to compliance standards ✦ Fintech & Payments — secure transaction processing, Stripe/PayPal integrations, reporting and reconciliation systems, PCI-conscious architecture ✦ E-Commerce Platforms — custom storefronts, order/inventory management, and integrations with payment gateways, CRMs, and ERPs ✦ Real Estate & Property Management Systems — listing platforms, tenant/lease management tools, and workflow automation for property teams ✦ AI-Powered Features — OpenAI/LLM integrations, intelligent document processing, and AI-assisted workflows added to existing .NET applications ✦ Legacy Modernization — turning outdated ASP.NET/VB.NET systems into maintainable, cloud-ready .NET 8 platforms without breaking what already works TECH STACK ──────────────────────── + Backend: C# · .NET 8 / .NET Core · ASP.NET Core · ASP.NET MVC · Web API · Entity Framework Core · LINQ · Blazor · SignalR · Microservices · REST & SOAP APIs + Frontend: Angular · React · TypeScript · JavaScript · HTML5 · CSS3 · Blazor UI + Cloud & DevOps: Microsoft Azure (App Services, Functions, AKS, Service Bus, Key Vault, Azure SQL) · AWS (EC2, Lambda, RDS, S3) · Azure DevOps · GitHub Actions · CI/CD · Docker · Kubernetes · Infrastructure as Code + Databases: SQL Server · PostgreSQL · Cosmos DB · MongoDB · Stored Procedures & Query Optimization for high-volume systems + Integrations: Stripe · PayPal · Twilio · SendGrid · OAuth 2.0 · HL7 · FHIR · CRM/ERP integrations HOW I WORK ──────────────────────── I stay involved from architecture through deployment — writing clean, documented, production-ready code, and communicating progress clearly at every step. I manage scope, timelines, and stakeholder expectations as carefully as I manage the codebase itself. Depending on what your project needs, I can work as a hands-on senior engineer, a solution architect, or a long-term technical lead. I'll tell you honestly, early, if I'm the right fit for what you're building. Send me your project scope and I'll respond within a few hours.

  • C#
  • Microsoft Azure
  • Azure DevOps Server
  • ASP.NET
  • ASP.NET MVC
  • ASP.NET Core
  • .NET Framework
  • AWS Development
  • Azure DevOps
  • DevOps
  • ADO.NET
  • Microsoft SQL Server
  • Web Form
  • ASP.NET Web API
  • .NET Core
  • VB.NET
  • .NET Stack
  • Azure App Service
  • Angular
  • DevOps Engineering

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