_   _    _    ____  ____  _   _    _   
| | | |  / \  |  _ \/ ___|| | | |  / \  
| |_| | / _ \ | |_) \___ \| |_| | / _ \ 
|  _  |/ ___ \|  _ < ___) |  _  |/ ___ \
|_| |_/_/   \_\_| \_\____/|_| |_/_/   \_\

Embedded  •  Robotics Safety  •  Distributed Backend  •  AI/RAG

harsha.sh — portfolio v1.0
$ whoami
HARSHA VARDHAN GUNTREDDI
B.Tech CSE @ Amrita Vishwa Vidyapeetham (AEEE AIR 369)
 
$ cat headline.txt
 
$ cat stack.txt
ESP32 / FreeRTOS → Spring Boot 3 → Kafka → Kubernetes → FastAPI + RAG
20K+
embedded / firmware LOC on real boards
<70ms
p95 assign/delivery in dispatch logic
24/7
self-healing NAT / CPS telemetry

About me

Systems engineer who can sit next to hardware with a multimeter at 2AM and write the backend service + CI/CD + monitoring that ships that hardware into the real world. Safety, reliability, clean handoff from prototype → production.

What I Build

Backend & Distributed Systems: Spring Boot microservices, Kafka/Flink streaming, real-time delivery/dispatch, PCI-aware tokenization vaults, rate-limited public APIs.

Cyber-Physical Systems & Robotics: autonomous landmine detection UGV with pulse-induction sensing, safety-radius navigation, confirm-dwell logic, MATLAB/Simulink controller design.

Embedded / Edge IoT: ESP32 NAT Wi-Fi repeater (AP+STA, hairpin NAT, OTA), Sony Spresense/STM32 data nodes for polyhouse/solar dryer control with MQTT/FTP fallback, watchdog recovery, brownout safety.

AI / RAG Automation: FastAPI + vector search (Qdrant/OpenSearch), doc extraction (Donut/LayoutLMv3), multilingual assistants, observability and guardrails.

Looking For

Roles where I own real systems end to end. I ship. I debug. I don't ghost when it breaks.

Embedded / CPS Backend / Platform Infra / DevSecOps AI for Operations

Fast Facts

  • Coimbatore, India — open to BLR / HYD / CHN
  • B.Tech CSE, Amrita Vishwa Vidyapeetham (2022–2026)
  • AEEE AIR: 369
  • AWS Academy: Cloud Foundations & Data Engineering
  • IIT Madras workshops: AI/ML, IoT on Raspberry Pi

Core Skills

Drop me in and I start delivering.

Embedded / CPS / Edge

ESP32 (ESP-IDF 5.x) Sony Spresense STM32 FreeRTOS UART / I2C / SPI OTA / Watchdog / Brownout MQTT / GSM / FTP MATLAB / Simulink

Backend / Distributed

Java 17 Spring Boot 3 Kafka Flink REST / gRPC / OpenAPI PostgreSQL / MongoDB / DynamoDB Redis CQRS / Saga / Idempotency OAuth2 / OIDC / mTLS

Infra / DevSecOps

Docker / Kubernetes GitHub Actions / Jenkins Prometheus / Grafana OpenTelemetry SonarQube / Fortify / Black Duck Nginx / TLS / NAT / VPN IDS/IPS (Zeek / Suricata) WAF (Nginx+ModSecurity)

AI / RAG / Doc Intel

Python / FastAPI LLM Agents (tool use) Hybrid Retrieval BM25+Vec Qdrant / OpenSearch Donut / LayoutLMv3 OCR Pydantic validation RAG Eval (RAGAS/TruLens) Multilingual Indic+English

Projects

Real builds, not class toy code.

Cyber-Physical Systems, Embedded, Edge & Security

Autonomous Landmine Detection UGV

[demo ↗]

Ground robot scanning for buried mines with pulse-induction sensing, KNN classification, safety-radius enforcement — never drives onto a suspected mine. Confirm-dwell logic, safe coverage path planning, MATLAB/Simulink controller design.

C / C++ Python MATLAB / Simulink KNN UGV control

ESP32 NAT Router & Secure Wi-Fi Repeater

[github ↗]

Custom ESP-IDF 5.x firmware: dual-mode AP+STA repeater with hairpin NAT, DHCP server, DNS proxy, mDNS reflector, MAC ACLs, rate limits, watchdog recovery, OTA with rollback, MQTT telemetry for remote health monitoring.

ESP-IDF / FreeRTOS lwIP NAT MQTT OTA / WDT

Smart Polyhouse / Solar Dryer CPS (Sony-SSUP)

Edge-native control on Sony Spresense / STM32 for agricultural drying and climate control. FreeRTOS-safe queues, hybrid connectivity (ESP32 Wi-Fi + GSM), MQTT/FTP uplink, watchdog-driven recovery for field reliability.

Sony Spresense STM32 FreeRTOS MQTT / GSM / FTP

IoT Telemetry & Device Ops Console

Spring Boot ingest API + React dashboard watching remote ESP32 / Spresense units. JWT auth, rate limiting, PostgreSQL heartbeat/last-seen models, alerting for offline nodes. Hardened Linux/Nginx deploy with TLS.

Spring Boot PostgreSQL React / TypeScript Nginx / TLS

Zero-Trust Remote Access & Threat Visibility Lab

pfSense/OPNsense HA (CARP+pfsync) across Untrust/Trust/DMZ/VPN zones; WireGuard + FreeRADIUS + TOTP; Zeek + Suricata into ELK; Nginx+ModSecurity (OWASP CRS); failover drills near-zero packet loss. Automated via Ansible + Docker.

pfSense / OPNsense WireGuard / IPsec IDS/IPS WAF / OWASP CRS Ansible

Deep Learning for Adaptive Encryption at the Edge

Lightweight ASCON & GIFT ciphers defended using RNN-based adaptive security policies on Raspberry Pi. Keeps comms hardened in hostile environments while staying real-time and power aware.

ASCON / GIFT Raspberry Pi RNN policy Edge security

Backend Platforms, Distributed Systems & Production Infra

Payments & Risk Microservices

Real-Time Payment Authorization (Spring Boot, Kafka, Oracle): idempotent auth/capture/void, Saga orchestration, OAuth2/mTLS, p95 < 50ms.
Card Tokenization & Vault: format-preserving tokenization with Vault Transit / SoftHSM, PCI-aware audit.
3DS 2.2 Emulator & SDK: ACS-like emulator, signed JWT, Redis state.
Streaming Fraud Pipeline: Kafka → Flink → scoring + Redis, exactly-once, Grafana SLOs.

Spring Boot 3 Kafka / Flink Redis OAuth2 / mTLS / PCI

Real-Time Dispatch • Search • Dynamic Pricing

Order & Delivery Assignment: Spring Boot + Kafka + Redis + DynamoDB, rider assignment at >50k events/min, p95 < 70ms.
Instant Search & Recommendation: Go microservice, gRPC, Elasticsearch+Redis, +18% CTR in A/B sims.
Dynamic Pricing & Surge Forecasting: AWS Lambda + Redis surge cache, DynamoDB rule store.

Java / Go Kafka / SQS Redis / DynamoDB Elasticsearch

Order Orchestration Platform

Domain-driven microservices (Java 17, Spring Boot 3, WebFlux) with CQRS+Saga for order lifecycle, Kafka/RabbitMQ events, Redis caching, API Gateway/BFF, and full DevSecOps pipeline (Jenkins, SonarQube, Fortify, Black Duck, blue/green deploys).

Spring Boot 3 / WebFlux Kafka / Redis CQRS / Saga Kubernetes / AWS

Industrial Telemetry & Historian

OPC UA + MQTT ingest into PostgreSQL/TimescaleDB with retention + rollups. FastAPI exposes /tags, /events, /trend with downsampling and pagination. Prometheus exporters + Grafana dashboards for ingest QPS and health.

FastAPI OPC UA / MQTT TimescaleDB Grafana

Alarm & Events Microservice

C#/.NET 8 service modeling limits, deadbands, hysteresis, shelving; CQRS + outbox to Kafka. REST/gRPC with idempotency keys, xUnit tests, container image signing, SBOM, secure supply chain.

.NET 8 CQRS / Kafka PostgreSQL gRPC / REST

minisqlpp-compiler

Compact SQL-subset compiler with LL(1) parser, AST, symbol table, semantic checks, and IR that can eval on CSV or emit vendor SQL (Oracle/SQLite). Includes optimizer (projection/selection pushdown, constant folding) and EXPLAIN-style pretty printer.

C++ / Parsing / AST LL(1) / Semantic Checks Query Optimization

AI / RAG / Intelligent Automation

Agentic Document QA & Automation

End-to-end RAG pipeline: semantic+layout chunking, hybrid retrieval (BM25 in OpenSearch + dense in Qdrant), bge reranker, tool-using agent (table extraction, OCR fallback), FastAPI+vLLM serving. RAGAS/TruLens eval, OpenTelemetry tracing, Grafana dashboards.

FastAPI Qdrant / OpenSearch LLM Agents RAGAS / TruLens

Contract / Invoice Extraction

Fine-tuned Donut & LayoutLMv3 for scanned contracts/invoices. Post-processing with regex + Pydantic validators and an LLM repair step for edge cases, exported as clean structured JSON/CSV.

Donut LayoutLMv3 Pydantic OCR / PDF parsing

RAG Observability & Safety Toolkit

Reusable eval harness with RAGAS, golden-set sampling, toxicity/PII guardrails, schema validation, drift monitoring, and OpenTelemetry traces into Grafana dashboards.

OpenTelemetry Prometheus / Grafana Safety / Guardrails

Multilingual KB Assistant (Indic + English)

Retrieval-augmented assistant for English + Indic FAQs using IndicTrans2 normalization and multilingual embeddings. FastAPI with Qdrant + Redis cache and BM25 fallback for when embeddings miss.

FastAPI Qdrant / Redis IndicTrans2 Sentence Transformers

Experience

Real teams. Real deployments. Real users.

Project Intern — Sony SSUP
India
Dec 2024 – Sep 2025

» Built Spresense/ESP32 edge CPS node for smart polyhouse drying: FreeRTOS pipeline, MQTT/FTP uplink, watchdog recovery.
» Wrote Java Spring Boot ingest API with JWT auth, rate limiting, PostgreSQL, Docker/K8s deploy, CI/CD, SonarQube gates.
» Shipped observability (Prometheus, OpenTelemetry, Grafana) so field deployments are debuggable instead of guesswork.
» Worked cross-team (hardware, data, platform), sprint-based delivery.

Freelance Infra / Full-Stack
2025

» Delivered production site + lead capture backend for a real industrial client.
» Set up Linux hosting (Nginx, SSL/TLS), DNS, uptime tuning, and simple admin portal.

B.Tech CSE
Amrita Vishwa Vidyapeetham, Coimbatore
Sep 2022 – Jun 2026

» Coursework: Distributed Systems, Networks, OS, DBMS, Algorithms, Embedded Systems, AI/ML.
» Workshops: IIT Madras (AI/ML, IoT on Raspberry Pi).
» AWS Academy Graduate: Cloud Foundations & Data Engineering.
» AEEE AIR: 369.

GitHub

HarshaGuntreddi
@HarshaGuntreddi ↗
public commits • firmware • backend • infra • AI/RAG
GitHub streak stats
// consistent activity matters more than buzzwords

Contact

Open for Embedded / Robotics Safety (CPS), Backend/Platform, Infra/DevSecOps, and Applied AI/RAG. Have something serious and want it shipped? Reach out.

Direct

Phone / WhatsApp
+91 7386117763
Location
India — BLR / HYD / CHN onsite available

Send a Message