
Subhajit Mandal
AI Engineer | Agentic AISystems | LLMApplications | Voice AI | RAG Pipelines | AI Business Automation
Salary / Daily rate
Freelance, open to permanent contract
Skills
About me
Intro
AI Engineer with 4+ years of experience architecting production-grade AI systems, LLM powered applications, and autonomous AI agents. Specialized in building RAG pipelines, Voice AI integrations (Vapi, OpenAI Whisper), and scalable async backends using FastAPI, OpenAI/Anthropic APIs, and vector databases (FAISS, Pinecone, ChromaDB). Experienced in end to end AI business automation using OpenClaw to orchestrate marketing, lead generation, personalised email outreach, content creation, multi-platform social posting, and e-commerce operations. One of few engineers globally with hands on MCP (Model Context Protocol) production experience. Proven ability to design and deploy GenAI powered microservices, implement prompt engineering and model evaluation frameworks, and eliminate manual workflows entirely through intelligent agent-to-API orchestration – reducing human intervention by 100% in deployed systems.
Work experience
AI Engineer
Virtual Employee Pvt Ltd
Sep 2024 - Present
2 years 2 months
Remote
– Architected and deployed an end to end Voice AI Agent integrating Vapi with Dentally CRM using FastAPI, Webhooks, and MCP (Model Context Protocol), enabling fully automated 24/7 appointment booking with zero manual intervention. – Designed 8+ REST API endpoints enabling real-time backend workflows: appointment search, slot booking, patient data updates, and dentist schedule validation all triggered autonomously by the Vapi voice agent. – Implemented production-grade security with HMAC webhook verification, raw body logging, and asynchronous request processing, ensuring reliable and secure communication between voice AI and backend services. – Built a conversation to action mapping engine that translates natural language voice interactions into structured API calls, reducing booking errors and eliminating 100% of manual scheduling overhead. – Deployed containerized FastAPI application to AWS EC2 with Nginx reverse proxy + Uvicorn workers, HTTPS, static IP exposure, and automated environment handling achieving 99.9% uptime. – Designed agent based workflows integrating LLM reasoning with backend APIs to automate real world business operations across the entire patient lifecycle. – Integrated OpenAI Whisper for real time speech to text transcription in voice agent pipelines, enabling accurate natural language understanding across diverse accents and noisy environments. – Leveraged OpenClaw to automate entire business processes including marketing, lead generation, content creation, and multi platform social posting (LinkedIn, Instagram), dramatically reducing manual effort across client campaigns. – Connected OpenClaw with email systems to send personalized outreach emails to leads based on their business profile, increasing engagement rates and streamlining the sales funnel. – Applied OpenClaw across diverse e commerce use cases automating product listing, inventory updates, customer communication, and order lifecycle management to run end to end e-commerce operations with minimal human intervention.
Associate Software Engineer / Python Developer
Mphasis (Client: Banking & Financial Services)
Feb 2022 - Jun 2024
2 years 5 months
– Developed and deployed Python-based backend services and REST APIs using Flask to support intelligent automation, data processing, and AI ready workflows in the BFSI domain. – Built and maintained RESTful APIs handling secure authentication, backend data exchange, and seamless integration with analytical dashboards, serving 1,000+ daily internal requests. – Designed optimised SQL queries and data models for relational and semi-structured data, supporting feature generation, data validation, and dynamic API responses with 40% faster query execution. – Created data-driven processing pipelines using Python enabling efficient data transformation, enrichment, and preparation for downstream ML and AI-based analytics systems. – Integrated backend services with enterprise tools (JIRA, Git, Confluence), improving traceability, version control, and delivery workflow efficiency. Built AI-ready data pipelines for BFSI datasets, including financial data preprocessing, validation, and analytics aligned with banking compliance requirements.
Associate
Amazon
Aug 2020 - Mar 2021
8 months
– Performed data analysis on customer complaints and product performance data to identify root causes, trends, and recurring patterns, informing product quality improvements. – Delivered actionable insights to stakeholders through data driven reports, contributing to measurable reductions in complaint resolution time.
Education
Narula Institute of Technology
B.Tech, Electrical Engineering
2016 - 2020
4 years 1 month
Licenses & certifications
Appium
Issued: –
Java 8
Issued: –
AI Engineer
Issued: –
Big Data Engineering
Issued: –