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Kartik S.

FullStack AI Developer | AI Agents, RAG & LLM Apps | Python, Next.js

Dehradun, India
$25 per hour
6 jobs
$600+ total earnings

Full Stack AI Developer – I build AI agents, RAG pipelines and LLM apps end to end, from the model layer to the dashboard your team uses. My RAG system at Aura Group (Sweden) is used daily by thousands of consultants. Your AI demo worked. Production failed. That's the gap I close. 6+ years | 40+ Full Stack & AI projects | CS Major | Only 5-star reviews ⭐⭐⭐⭐⭐ MY TWO BEST BUILDS: 1. Trust & Growth – Aura Group, Sweden An internal AI product used daily by thousands of the firm's consultants. A RAG system that reads financial filings, news, reviews and market data on publicly traded companies and scores them on trustworthiness and expected growth – every answer cited, so a consultant can verify it before acting. That's enterprise AI as it actually exists: not a demo, a tool people make decisions with. 2. Nesoi – AI-native learning platform (nesoi.ai) Founding engineer and first AI Developer on the team, zero to production. The platform turns documents, decks and video into interactive lessons with a real-time AI instructor that adapts pace, language and delivery per learner, across 130+ languages. Live adaptive AI is unforgiving – there is no retry queue when a learner is mid-lesson. Other systems I've shipped: – Orchy AI – agent orchestration platform, end to end: create agents, configure tools, memory and guardrails, chain them into multi-agent workflows, trigger from Telegram or on a schedule – AI voice agents calling inbound leads in under 60 seconds – qualification, objection handling, booked straight into Google Calendar – Speed-to-lead systems: form submission → AI call → WhatsApp → booked appointment, no human in the loop – 100K+ documents through OCR + RAG pipelines WHAT I BUILD Full Stack AI Development – React/Next dashboards, admin panels and internal tools, so one owner carries it from agent logic to the screen the user sees. AI Agent Developer – LangChain, LangGraph and custom orchestration: tool calling, memory, guardrails, multi-agent handoff, error handling, observability and evals. Anyone can call an API; few can keep an agent stable. MCP Developer – custom MCP servers connecting your APIs, databases and internal tools to Claude, Claude Code, ChatGPT and Cursor. Most teams are stuck here, and few developers have actually shipped one. RAG/LLM Developer – pgvector and Postgres retrieval: chunking strategy, hybrid search, reranking, grounded answers with citations. Retrieval that returns the right chunk rather than the nearest one is the line between an engineer and a prompt writer. Enterprise AI Integration – OpenAI, Claude and open models dropped into products that already have users, without breaking what already works. Built for teams where downtime has a cost. Python AI Developer – FastAPI, Django, PostgreSQL, Redis, Celery, background workers, RBAC, clean REST APIs. The backend the AI layer sits on, built by the same person. AI Voice Agent Developer – Vapi, Retell, ElevenLabs, SIP and phone integration, CRM-connected inbound and outbound calling. HOW I BUILD: Most AI projects fail in the same place: the demo works, production doesn't. Retrieval returns the wrong chunk. The agent loops. The model updates and outputs drift. Building for thousands of daily enterprise users teaches you that the real job is month six, not launch day – logging, evals, fallbacks, retries, human review where it matters, and regression tests that prove the system still works after the next model release. Agents: langchain, langgraph, mcp server, tool calling, function calling, multi-agent systems, agentic workflows, prompt engineering, rag pipeline, retrieval augmented generation, evals, observability. Stack: python, fastapi, django, typescript, nextjs, react, nodejs, postgres, pgvector, redis, docker, aws, gcp, cloudflare, stripe, playwright. Models & integrations: openai api, anthropic claude api, claude code, n8n, make, airtable, hubspot, gohighlevel, slack, whatsapp business api, telegram. HOW I WORK: - Free scoping call – you talk to the developer building it, not an account manager - Architecture and an honest cost before any code - You own the code – your repo, your infrastructure, no lock-in - Documented, logged and supported after launch; retainers welcome 🤝 Need a Full Stack AI Developer who has shipped at enterprise scale? Send a message or an invitation and I'll record you a personalised Loom showing exactly how I'd build your system. Full Stack AI Developer, AI Developer, AI Engineer, Python AI Developer, AI agent developer, LangChain developer, LangGraph, MCP developer, RAG developer, LLM developer, OpenAI developer, Claude API developer, FastAPI, Next.js, vector database, API integration

Neha S.

AI/ML Developer|AI Agents, LLM & RAG|Python|All CSPs

Mohali, India
$18 per hour
41 jobs
$80K+ total earnings

🚀 𝐀𝐈 & 𝐅𝐮𝐥𝐥-𝐒𝐭𝐚𝐜𝐤 𝐒𝐨𝐥𝐮𝐭𝐢𝐨𝐧𝐬 | 𝐇𝐚𝐧𝐝𝐬-𝐎𝐧 𝐀𝐈/𝐌𝐋 𝐄𝐧𝐠𝐢𝐧𝐞𝐞𝐫 | 𝐎𝐧-𝐓𝐢𝐦𝐞 𝐃𝐞𝐥𝐢𝐯𝐞𝐫𝐲 𝐨𝐫 𝐘𝐨𝐮𝐫 𝐌𝐨𝐧𝐞𝐲 𝐁𝐚𝐜𝐤! I'm an AI/ML specialist focused on delivering practical machine learning and data analysis solutions for businesses. With expertise in programming, data analysis, and AI development, I help clients transform their data into actionable insights and automated systems. I specialize in projects involving machine learning model development, data analysis, and AI implementation. Whether you need predictive analytics, intelligent automation, or custom AI solutions, I deliver work that aligns with your business goals. Let's discuss how I can help your project succeed. 👉 Let’s build your AI-powered future together. ✅ What I Build: • LLM Applications: RAG pipelines, chatbots and copilots, document AI, semantic search, structured data extraction • Model Customization: Fine-tuning (LoRA/QLoRA, RLHF/DPO), prompt optimization, evals and guardrails, open-weight model serving (vLLM) • Healthcare AI: Clinical trial automation, medical document generation, HIPAA-compliant systems • AI Agents: Multi-agent systems, MCP (Model Context Protocol) tool integrations, LangGraph orchestration, function/tool calling, agentic workflow automation • Full-Stack AI Products: Python/FastAPI backends, React frontends, Kubernetes, CI/CD across AWS, GCP, Azure 🔧 Technical Stack: AI/ML: GPT-5, Claude, Gemini, Llama, DeepSeek, Qwen; fine-tuning (LoRA/QLoRA, PEFT, RLHF/DPO); RAG and GraphRAG, hybrid search, rerankers, embeddings Agents: MCP, LangGraph, LangChain, LlamaIndex, CrewAI, OpenAI Agents SDK, structured outputs, tool calling Serving & MLOps: vLLM, Ollama, AWS (SageMaker, Lambda, ECS/EKS), GCP (Vertex AI), Azure AI Foundry, Kubernetes, Docker, MLflow, Weights & Biases Evals & Observability: LangSmith, Langfuse, RAGAS, guardrails, LLM cost optimization Databases: PostgreSQL/pgvector, Pinecone, Qdrant, Weaviate, ChromaDB, Elasticsearch, MongoDB, Redis Languages: Python, TypeScript/JavaScript, SQL, Java, Go Frameworks: PyTorch, Hugging Face, FastAPI, React, TensorFlow, Scikit-learn 💡 𝗜𝗻𝗱𝘂𝘀𝘁𝗿𝗶𝗲𝘀 𝗜’𝘃𝗲 𝗪𝗼𝗿𝗸𝗲𝗱 𝗪𝗶𝘁𝗵 Healthcare | Fintech | E-commerce | EdTech | Logistics | Manufacturing ⚡ 𝗪𝗵𝗮𝘁 𝗖𝗹𝗶𝗲𝗻𝘁𝘀 𝗚𝗲𝘁 𝗪𝗼𝗿𝗸𝗶𝗻𝗴 𝗪𝗶𝘁𝗵 𝗠𝗲 ✔ Production-ready AI systems (not prototypes) ✔ Clean, scalable, and maintainable architecture ✔ Fast communication and reliable delivery ✔ End-to-end ownership from design to deployment ✔ Strong focus on real business outcomes 🎯 𝗠𝘆 𝗔𝗽𝗽𝗿𝗼𝗮𝗰𝗵 I combine deep technical expertise with a product mindset. My goal is to build AI systems that are reliable, scalable, and actually useful in real-world operations not just experimental demos. If you’re looking to build AI agents, automate workflows, or create scalable AI-powered applications, I can help you turn that idea into a working production system. 𝐋𝐞𝐭’𝐬 𝐛𝐮𝐢𝐥𝐝 𝐬𝐨𝐦𝐞𝐭𝐡𝐢𝐧𝐠 𝐢𝐦𝐩𝐚𝐜𝐭𝐟𝐮𝐥. AI Chatbot Development | AI Agent Development | LLM (Large Language Models) | Python Developer | Full Stack Developer | React Developer | Django Developer | AWS Cloud | Machine Learning Engineer | RAG (Retrieval-Augmented Generation) | NLP Developer | API Integration | AI Automation | Cloud Deployment | Custom Web App Development | AI Automation | Deep Learning

Mohsin R.

AI Agent & LLM Developer | Agentic AI, LangChain, RAG, Chatbots, n8n

Lahore, Pakistan
$25 per hour
90 jobs
$90K+ total earnings

Top Rated Plus AI developer, $80K+ earned across 90 Upwork contracts. I build AI agents, LLM applications, and AI chatbots that run in production: agentic workflows, LangChain and RAG pipelines, and the full-stack product around them. 10+ years in Python, Node.js, React and Next.js means the agent, the API, the dashboard and the deployment all come from one developer. CURRENT WORK • Integration Engineer on a production AI operating system (DATAONE): AI and API integrations, backend services, automation workflows, and system-to-system data flows, built for reliability and observability. • Senior Tech Lead / Integration Engineer on a solo contract covering architecture through deployment. • AI-Native Product Engineer building AI features into a live product. DELIVERED ON UPWORK • Email-to-OpenAI service: inbound mail through AWS SES into Python Lambda functions, shipped with a Bitbucket deploy pipeline. • Xero API data engineering across two contracts: OAuth onboarding, paginated extraction, and handling source data that keeps changing. • Python website and API integration work connecting third-party services to client systems. • Data science and AI specialist contract. • WordPress plugin wired into the ChatGPT API. • Digital Human app for Shopify. • Python simulation models of real-world behavior. PLATFORM WORK • Stack AI: no-code AI workflow builder. I built the drag-and-drop agent builder UI, the backend RAG assistants on LangChain and Pinecone, and the workflow orchestration. • Chatful: chat and voice bots with a Django backend, React UI and WebRTC. • Quizy: GPT-powered quiz and tutoring chatbot on Django, Celery and WebSockets. • Kodezi: AI coding assistant backend in FastAPI. • MagicHour and Tavus: real-time AI video with LLM scripting, voice cloning, avatar streaming and video rendering APIs. • Neptune: ML experiment tracking platform in Python and Flask on Kubernetes. WHAT I BUILD FOR CLIENTS ◆ AI Agents & Agentic AI: agents that plan multi-step tasks, call your tools and APIs, and hand off to a human when they should. LangChain, OpenAI API, Claude API, n8n. ◆ RAG & Knowledge Assistants: document ingestion, embeddings and Pinecone vector search, so answers come from your data instead of the model's guesses. ◆ AI Chatbot Development: support, lead capture, tutoring and internal assistant chatbots with conversation memory and a clean admin side. ◆ LLM Integration: OpenAI and Claude added to existing products for structured extraction, summarization, classification and content generation, with prompt engineering tested on real inputs. ◆ AI Automation & Integrations: n8n workflows and custom services connecting LLMs to email, databases, CRMs and third-party APIs, with OAuth, retries and error handling that hold up in production. ◆ Full-Stack & Deployment: FastAPI, Django, Node.js, NestJS, React, Next.js, TypeScript, PostgreSQL, MongoDB, Redis, AWS (Lambda, S3, EC2), Docker, GitHub Actions. HOW I WORK ✓ Scope, milestones and acceptance criteria agreed before any code ✓ Claude Code and Cursor in my daily workflow, with every AI-assisted change reviewed before it ships ✓ Regular updates without you having to chase them ✓ An honest answer when an LLM is the wrong tool for the job Send me a short brief on the workflow you want automated or the AI feature you want built. I'll reply with an honest read on scope, approach and cost.

Rohit K.

AI/ML Expert, AI Agent, LLM, RAG, LangChain, n8n, Voice AI, React, Vue

Noida, India
$15 per hour
138 jobs
$400K+ total earnings

Senior AI Engineer with $400K+ earned on Upwork, 26,000+ hours, and 110+ successful projects building production software for startups and enterprises. I specialize in building AI Agents, Voice AI systems, MCP servers, RAG applications, and workflow automations that integrate with CRMs, APIs, and business platforms. I've built solutions including AI Sales & Customer Support Agents, Voice AI Receptionists, AI Research Assistants, RAG-powered knowledge bases, MCP servers, and intelligent workflow automations using OpenAI, Claude, LangGraph, n8n, and modern cloud infrastructure. From architecture and development to deployment, I build scalable AI solutions that help businesses automate operations, reduce costs, and launch AI products faster. 🚀 What I Do Whether you're launching an AI startup or adding AI to an existing product, I design and deliver production-ready AI solutions—from AI agents and Voice AI to RAG applications, workflow automation, and AI-powered web & mobile applications. 🤖 AI Agents & Automation ✅ AI Sales, Customer Support & Research Agents ✅ Multi-Agent Systems (LangGraph, LangChain, CrewAI, AutoGen) ✅ AI Assistants & Human-in-the-Loop Workflows 🎙 Voice AI ✅ AI Receptionists & Call Agents ✅ Inbound & Outbound Voice Automation ✅ CRM Integration, Transcription & Analytics Platforms: Vapi, Retell AI, ElevenLabs, Deepgram, Twilio 🔥 MCP, RAG & LLM Solutions ✅ Custom MCP Servers ✅ OpenAI, Claude & Gemini Integrations ✅ RAG Applications & Vector Databases ✅ Tool Calling & Enterprise AI Solutions 🔄 Workflow Automation ✅ n8n, Make, Zapier & Power Automate ✅ API Integrations & ETL Pipelines ✅ CRM, ERP & Business Process Automation 🔗 CRM & ERP Integration ✅ Salesforce, HubSpot, GoHighLevel, Zoho, Monday ✅ NetSuite, SAP, QuickBooks, Stripe & Custom APIs 💻 Full-Stack Development ✅ AI-Powered Web Applications (React, Next.js, Python, Node.js) ✅ Mobile Apps (React Native, Flutter) ✅ FastAPI, Django, PostgreSQL, MongoDB & Redis 💡 Why Work With Me ✔ Expert-Vetted (Top 1%) AI Engineer ✔ $400K+ Earned • 100% Job Success ✔ End-to-End AI, Web & Mobile Development ✔ Production-Ready, Scalable Solutions ✔ Clear Communication & Reliable Delivery Let's build something amazing together.

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LLM specialist hiring guide

Large Language Model (LLM) specialists help businesses implement AI tools for real tasks, from creating chatbots to managing content systems. LLM projects can range from lightweight prompt engineering to full-scale, production-grade systems that integrate with your data, tools, and workflows. 

What does an LLM specialist do?

An LLM specialist designs, develops, and fine-tunes large language models (LLMs) to perform specific tasks, such as automating customer support or generating marketing copy. They can help connect powerful AI technology with your practical business needs.

The work of an LLM specialist often involves several key responsibilities that can help customize AI for your business:

  • Model fine-tuning. Modifying pretrained models like GPT, Claude, or Llama with your company's specific data to improve relevance and accuracy for your use case.
  • Prompt engineering. Crafting precise instructions that help models generate accurate, useful responses for your specific needs.
  • Data preparation. Cleaning, structuring, and labeling datasets for training or fine-tuning models to ensure quality outputs.
  • API integration. Connecting LLMs to your existing software and applications so they work seamlessly within your current workflows.
  • Evaluation and safety. Testing models for performance, bias, and accuracy while implementing safeguards for responsible AI use.
  • Retrieval-augmented generation (RAG). Designing systems that let models reference your proprietary documents or databases in real time to improve factual accuracy and reduce hallucinations.
  • Tooling and orchestration. Building pipelines and agents that can call external tools, trigger workflows, or chain multiple model calls to accomplish complex tasks.
  • Monitoring and observing. Setting up telemetry, evaluation harnesses, and quality dashboards to track drift, latency, cost, and user satisfaction in production.
  • Compliance and privacy. Implementing data handling, access controls, and redaction strategies to protect sensitive information and meet regulatory requirements.

Adopting LLMs is no longer limited to early adopters; organizations across industries use them to streamline operations, reduce costs, and improve customer experiences. Think of an LLM specialist as someone who takes a powerful AI model and customizes it to solve your specific business challenges. For instance, a B2B SaaS startup could hire an LLM specialist to build a chatbot that can process and retrieve information from its product catalog or create a content generation system trained to replicate its brand voice.

How much does hiring an LLM specialist cost?

Hiring an LLM specialist typically costs similar to a machine learning engineer, at $50-$150 per hour. Rates vary based on experience, project scope, and engagement length. Explore Upwork hourly rates for related roles across the platform.

Review these typical costs for LLM projects commonly found on Upwork;

Project Type

Typical Cost Range

Experience Level

Example Deliverables / Scope

Prompt engineering

$500-$2,500/project

Entry-level to mid-level

• Basic prompt templates

• Initial chatbot setup

• Simple API integration

Model fine-tuning

$2,500-$10,000/project

Mid-level to senior-level

• Custom model training

• Dataset preparation

• Performance optimization

Custom LLM development

$10,000+/project

Senior-level or specialist

• End-to-end model deployment

• Multi-model integration

• Production-ready systems

Ongoing support

$3,000-$8,000/month

Mid-level to senior-level

• Model maintenance

• Regular updates

• Performance monitoring

Strategic consulting

$150-$300/hour

Expert-level

• AI roadmap development

• Team training

• Architecture planning

How to hire a freelance LLM specialist on Upwork

Finding the right LLM specialist starts with a clear plan and a detailed job description. Upwork provides tools that can help you navigate each step of the hiring process, from defining your project to starting work.

Step 1: Post a detailed job description

A detailed job post can help attract qualified specialists. A strong job post often includes:

  • Clear project goal. Describe the business problem you want to solve, such as "Develop an AI-powered content summarization tool for internal documents."
  • Specific tasks. List what the specialist will do, like "Fine-tune a Llama model using our technical documentation."
  • Required skills. Include technical requirements such as Python, PyTorch, or experience with specific LLM frameworks.
  • Project deliverables. Define expected outcomes, such as "A deployed API endpoint for the fine-tuned model with documentation."
  • Timeline and budget. Specify your project timeline and whether you prefer hourly or fixed-price arrangements.

For guidance on crafting effective posts, review Upwork's job description template and examples. To get started quickly, you can use Upwork's Job Post Generator, powered by Uma™, Upwork's Mindful AI, to draft an LLM specialist job description for your review.

Step 2: Review proposals and portfolios

Once you post a job, Upwork's AI can suggest candidates that may be a good fit. You can also use the platform's filters to refine your search for specialists. Here are a few ways you can evaluate candidates on Upwork:

  • Use skill filters. Search for specific technical skills like "LLM fine-tuning" or "prompt engineering."
  • Check success metrics. Look for freelancers with high Job Success Scores, which indicate consistent client satisfaction.
  • Review talent badges. Focus on Top Rated, Top Rated Plus, or Expert-Vetted professionals who have proven track records on Upwork.
  • Examine portfolios. Look for case studies similar to your needs, as detailed project descriptions can be more informative than code samples alone.
  • Read client feedback. Reviews on Upwork can help you understand a candidate's communication style, reliability, and work quality.

You can use Upwork’s instant video interviews to screen applicants for a best-fit shortlist, with Uma providing side-by-side candidate comparisons.

Step 3: Interview top candidates

Structured interviews can help you assess both technical expertise and communication skills. For interview strategies, explore common Upwork interview questions and answers.

Consider asking questions like:

  • "Can you walk me through an LLM project you're proud of?" This can reveal their problem-solving approach and technical depth.
  • "How would you approach fine-tuning a model for our specific industry?" Their answer can show strategic thinking and relevant experience.
  • "What steps do you take to prevent issues like hallucinations or biased outputs?" This can demonstrate their understanding of AI safety and quality control.

For quick assessments, you could book a paid consultation through Upwork to evaluate expertise before committing to a larger project. Upwork Messages allows you to schedule and conduct live video interviews on the platform, with call transcripts and summaries available after the calls.

Step 4: Define success metrics and begin work

Once you’ve found the right fit, you can send a contract directly through the Upwork marketplace. Contracts protect both parties and help collaborations be successful from beginning to end.

  • Align on measurable goals (e.g., accuracy targets, latency budgets, cost per request)
  • Define acceptable use, data retention, and escalation policies. 
  • Establish an evaluation plan with both offline tests and real-user feedback to guide iterative improvements.
  • Provide environment access, sample data, documentation, and a single point of contact. 
  • Agree on communication cadences, demo schedules, and delivery milestones. 
  • Clarify ownership of code, models, and datasets
  • Ensure that security requirements are documented early.

How much does hiring an LLM specialist cost?

Hiring an LLM specialist typically costs similar to a machine learning engineer, at $50-$150 per hour. Rates vary based on experience, project scope, and engagement length. Explore Upwork hourly rates for related roles across the platform.

Review these typical costs for LLM projects commonly found on Upwork;

Prompt engineering

$500-$2,500/project

Entry-level to mid-level
  • Basic prompt templates
  • Initial chatbot setup
  • Simple API integration

Model fine-tuning

$2,500-$10,000/project

Mid-level to senior-level
  • Custom model training
  • Dataset preparation
  • Performance optimization

Custom LLM development

$10,000+/project

Senior-level or specialist
  • End-to-end model deployment
  • Multi-model integration
  • Production-ready systems

Ongoing support

$3,000-$8,000/month

Mid-level to senior-level
  • Model maintenance
  • Regular updates
  • Performance monitoring

Strategic consulting

$150-$300/hour

Expert-level
  • AI roadmap development
  • Team training
  • Architecture planning

Frequently asked questions

Is hiring an LLM specialist worth it?

Yes, hiring a freelance LLM specialist can be worth it for businesses looking to gain a competitive edge with custom AI solutions. Specialists can help you build tools for customer service automation that can increase agent productivity by 15% or content generation systems that are tailored to your specific business needs.

What's the difference between an LLM specialist and an AI engineer?

An LLM specialist focuses exclusively on large language models, while an AI engineer often has a broader skill set that may include machine learning, computer vision, and data science.

What does LLM stand for?

LLM stands for large language model, a type of AI trained on massive datasets to process and generate human-like text.

How long does it take to implement an LLM solution?

The timeline to implement an LLM solution depends on the project's complexity. A simple API integration could take a few weeks, while developing a custom-trained model from scratch might take several months.

Do I need proprietary data to get value from an LLM?

You don't necessarily need proprietary data to get value from an LLM. Many teams start with prompt engineering on general-purpose models to validate value quickly. Proprietary data often enhances relevance and accuracy, especially for domain-specific tasks, but you can phase it in after a successful pilot.

How do I measure ROI for LLM projects?

To measure ROI for LLM efforts, tie outcomes to business KPIs such as reduced handle time, increased self-serve resolution, higher content throughput, fewer manual reviews, or improved lead conversion. Track both cost (infrastructure, usage, maintenance) and benefits (time saved, revenue lift, quality improvements).

Which tools and frameworks might an LLM specialist use?

LLM specialists may work with vector databases, orchestration libraries, model evaluation suites, and machine learning operations platforms. The exact stack depends on your requirements, security constraints, and existing infrastructure.

Can an LLM specialist work with my existing tech stack?

Yes, LLM specialists can often work with existing tech stacks. They commonly integrate with REST/GraphQL APIs, message queues, CRMs, CMSs, data warehouses, and cloud platforms. Sharing architectural diagrams and access constraints up front can help ensure a smooth integration plan.