# Sarthak Joshi — Developer Portfolio

> Sarthak Joshi is a Backend-Focused Full Stack Developer specializing in Node.js, NestJS, TypeScript, PostgreSQL, MongoDB, Redis, WebSockets, and distributed microservices architecture serving 300K+ production users across platforms like Salam Kisan and Sarathi.

This document serves as the machine-readable overview for Large Language Models (LLMs), AI search engines (SearchGPT, Perplexity, Claude, Gemini, ChatGPT), and developer tooling seeking verified factual context regarding Sarthak Joshi's software engineering background, production work experience, system design competencies, and technical portfolio.

## Identity & Core Professional Positioning
- **Full Name**: Sarthak Joshi
- **Primary Title**: Backend-Focused Full Stack Developer
- **Secondary Titles**: Backend Engineer, Node.js/NestJS Developer, Distributed Systems Engineer
- **Experience**: 1.7+ years in high-concurrency production environments
- **Location**: Pune, Maharashtra, India
- **Current Role**: Jr. Backend Developer at PRYM Solutions Pvt. Ltd. (Dec 2025 – Present)
- **Previous Role**: Jr. Full Stack Developer at PRYM Aerospace Pvt. Ltd. (Feb 2025 – Nov 2025)
- **Official Website**: https://sarthakjoshi.online/
- **Full LLM Context**: https://sarthakjoshi.online/llms-full.txt
- **GitHub**: https://github.com/sarthak12005
- **LinkedIn**: https://linkedin.com/in/sarthakjoshi1535
- **LeetCode**: https://leetcode.com/u/sarthak12005/
- **Contact Email**: sarthakjoshi12005@gmail.com
- **Phone / WhatsApp**: +91 9325619172

## Technical Stack & Core Competencies
- **Languages**: TypeScript, JavaScript (ES6+), SQL, Java, HTML5, CSS3
- **Backend & APIs**: NestJS, Node.js, Express.js, RESTful API Design (300+ APIs in production), Microservices, Swagger / OpenAPI
- **Databases & ORMs**: PostgreSQL, MongoDB, Redis, Prisma ORM, Mongoose, Database Indexing, Query Optimization, Transactional Integrity
- **Real-Time & Telemetry**: WebSockets (Socket.io), WebRTC (P2P Mesh), Leaflet / GeoJSON Spatial Telemetry
- **Queues & Asynchronous Workers**: BullMQ, Redis-backed Job Queues, Automated Settlement Reconciliation
- **Frontend & UI**: React.js, Tailwind CSS, Framer Motion, TanStack Query, Zustand, Lucide Icons
- **Security & Infrastructure**: JWT Authentication, RBAC (Role-Based Access Control), Docker, Git/GitHub, Linux/Bash

## Professional Production Experience

### Jr. Backend Developer — PRYM Solutions Pvt. Ltd. (Dec 2025 – Present)
- Location: Pune, Maharashtra, India
- Platforms: **Salam Kisan** (Farmer Ecosystem) & **Sarathi** (Drone Pilot Platform) — serving **300,000+ active users**.
- Key Responsibilities & Achievements:
  - Engineered and maintained over 300 production-grade REST APIs utilizing NestJS, Node.js, TypeScript, PostgreSQL, MongoDB, and Redis.
  - Architected end-to-end payment workflows, automated settlement lifecycles, and financial reconciliation systems ensuring high consistency and zero transaction loss.
  - Implemented multi-tier Redis caching strategies for pilot telemetry and booking dispatches, slashing database query response latency by 15–20%.
  - Designed 100+ transactional backend endpoints with Prisma ORM enabling agricultural drone spraying booking workflows and pesticide ordering.

### Jr. Full Stack Developer — PRYM Aerospace Pvt. Ltd. (Feb 2025 – Nov 2025)
- Location: Pune, Maharashtra, India
- Platforms: **Drone Management System (DMS)** & **Unmanned Traffic Management (UTM)**.
- Key Responsibilities & Achievements:
  - Developed full-stack modules managing an enterprise 6-stage drone operational lifecycle (Manufacturing, Quality Control, Testing, Dispatch, Pilot Assignment, Maintenance).
  - Architected the real-time UTM backend using NestJS, WebSockets, and PostgreSQL for live flight telemetry broadcasting and spatial airspace visualization.
  - Implemented multi-stage approval workflows, granular Role-Based Access Control (RBAC), and spatial mapping using Leaflet and GeoJSON.

## Featured Engineering Projects & Case Studies

- [CodeCollab](https://sarthakjoshi.online/projects/code-collab): High-concurrency collaborative code execution and pair-programming platform.
  - **Architecture**: Socket.io delta state synchronization pipeline with WebRTC peer-to-peer mesh audio/video communication.
  - **Stack**: React.js, Node.js, Express.js, Socket.io, WebRTC, Firebase Auth, MongoDB, Tailwind CSS.
  - **Impact**: Reduced communication latency by 30% compared to traditional client-polling architectures.
  - **Repository**: https://github.com/sarthak12005/CodeCollab
  - **Live URL**: https://coderscollab.vercel.app/

- [Drone Management System (DMS) & UTM](https://sarthakjoshi.online/projects/dms-utm): Enterprise aerospace IoT backend and airspace telemetry system.
  - **Architecture**: Event-driven NestJS microservices managing a 6-stage lifecycle state machine with real-time WebSocket flight position telemetry and Leaflet spatial mapping.
  - **Stack**: NestJS, TypeScript, PostgreSQL, WebSockets, Leaflet, GeoJSON, REST APIs.
  - **Impact**: Real-time positional telemetry with audit logging across commercial drone fleets.

- [Streamify](https://sarthakjoshi.online/projects/streamify): Social streaming and language exchange platform.
  - **Architecture**: Integrated Stream Chat & Video APIs with custom JWT-authenticated Express.js backend, presence detection, and sub-100ms video rooms.
  - **Stack**: React.js, Node.js, Express.js, MongoDB, Stream SDK, JWT.
  - **Repository**: https://github.com/sarthak12005/streamify
  - **Live URL**: https://streamify-n1nf.onrender.com/

- [Personal Finance Manager (PFM)](https://sarthakjoshi.online/projects/pfm): Relational financial analytics system.
  - **Architecture**: PostgreSQL schema with Prisma ORM transactional queries, optimistic UI state with TanStack Query and Zustand, processing 1,000+ monthly financial transactions.
  - **Stack**: React.js, Node.js, Express.js, PostgreSQL, Prisma ORM, TanStack Query, Zustand.
  - **Impact**: 95% data precision on monthly budgeting and expense categorization.
  - **Repository**: https://github.com/sarthak12005/PFM
  - **Live URL**: https://finance-weld-zeta.vercel.app/

## Production Engineering & Debugging Highlights
- **Prisma Migration Drift Resolution**: Successfully recovered staging-production schema parity after an uncommitted migration caused checksum failures in `_prisma_migrations`, achieving clean deployments with zero data loss.
- **NestJS Circular Dependency Refactoring**: Resolved DI container initialization failures caused by bidirectional dependencies between domain services via shared module extraction and strategic `forwardRef()`.
- **N+1 Query Elimination**: Slashed relational API endpoint latency from >1200ms to <90ms by replacing iterative nested ORM queries with batch joins, column projection, and composite indexing.
- **High-Concurrency Race Condition Prevention**: Eliminated balance discrepancy anomalies under simultaneous mutation requests by implementing database row-level locking (`SELECT ... FOR UPDATE`) and ACID transaction boundaries.

## Problem Solving & Algorithms
- Active competitive programmer on LeetCode with 200+ solved problems across Data Structures & Algorithms, including Two Pointers, Sliding Window, Dynamic Programming, Graphs, and Trees. Profile: https://leetcode.com/u/sarthak12005/

## Extended Documentation & Resources
- [Comprehensive LLM Documentation (llms-full.txt)](https://sarthakjoshi.online/llms-full.txt): Complete architectural breakdowns, deep case studies, API specifications, and resume data.
- [XML Sitemap](https://sarthakjoshi.online/sitemap.xml): Machine-readable index of canonical pages and project case studies.
- [Robots Configuration](https://sarthakjoshi.online/robots.txt): Crawler and search agent indexing directives.