Yogeshwaran R

I work in a product organization and build freelance applications like Lendbook on the side — backend, front end, automation and AI systems.

Python · FastAPI · gRPC · Postgres · LangGraph · React · Angular · TypeScript

What I build

• Document & data pipelines

  Ingestion, OCR, extraction, validation. Getting structured, trustworthy records out of whatever format they arrive in.

• AI features that hold up

  Agents, retrieval and LLM integrations built to be repeatable and affordable, with the cost and failure modes understood before launch.

• Backend & API systems

  Python and FastAPI services, REST and gRPC, Postgres schema design, background jobs, queues and real-time streams.

• Full-stack delivery

  React and Angular front ends on top of it all — dashboards, review workflows, admin surfaces and live status.

Projects

1. Lendbook

   Freelance / Lending Platform

   A clean lending operations product for tracking borrowers, loans, repayments and follow-ups in one place.

   React · TypeScript · Tailwind · Python · FastAPI · Postgres

2. Invoice Processing System

   Accounts Payable / Receivable

   An end-to-end AP/AR platform — invoices in, reconciled and audited records out.

   Python · FastAPI · gRPC · Postgres · SQLAlchemy · React · TypeScript

3. Document Intelligence Pipeline

   Extraction & Classification

   Turning PDFs, scans and photographs into structured, verified data at scale.

   Python · Gemini · LangChain · Pydantic · gRPC · Postgres · Neo4j

4. Timesheet Processing & Billing Audit

   Workforce & Payroll

   Timesheets arrive as spreadsheets, PDFs, photographs and email bodies. All of it becomes billable hours.

   FastAPI · LangGraph · Postgres · Redis · React · TypeScript · AWS

5. Multi-tenant Auth & Access

   Identity & Authorisation

   Single sign-on, tenant isolation, and permissions that admins configure instead of developers hard-coding.

   Python · FastAPI · Keycloak · OAuth2 · gRPC · Postgres · Angular

6. Agentic Chat & Retrieval

   AI Assistant / RAG

   Ask a question in plain language. The right agent answers it from your own documents and data.

   LangGraph · LangChain · pgvector · Neo4j · Postgres · gRPC · Python

7. Accounting Integrations

   Connectors & Sync

   Two-way sync with the accounting systems businesses already run on.

   Python · FastAPI · Pub/Sub · Postgres · REST · Cloud Scheduler

Experience

• 2025 — Present

  Full-stack & AI Engineer

  Product company (B2B SaaS)

  Currently working in an organization while also building freelance applications. My day-to-day work covers document intelligence, finance automation, backend services and the interfaces on top of them.

• Freelance

  Lendbook & independent builds

  Remote — worldwide

  Building Lendbook as my freelance application and taking on practical full-stack work where I can own the product from idea to shipped workflow.

Contact

• yogesh19012004@gmail.com
• github.com/yogesh1901
• linkedin.com/in/yogeshwaran-rajasekar

Lendbook is my freelance application. Other projects reflect the kind of systems I build in my current organization.