Devatraj Bhattacharjee

About me

Backend & AI engineer at Info Edge, working on Jeevansathi. Before that, an intern at 99acres and a computer science student at NIT Patna. Shipped changes across dozens of production microservices.

Experience

Software Engineer

Info Edge India Ltd · Jeevansathi.com

07/2025 – Present

Backend & AI engineer on India's matrimony platform: real-time GenAI matchmaking, LLM cost optimisation, and replacing paid vendors with in-house systems.

  • ~$45Ka year saved by replacing a paid astrology API with milanSathi
  • $70Ka year saved by replacing Firebase Remote Config, at 10M+ requests a day
  • 85%semantic-cache hit ratio on LLM calls, with 40% lower message latency
  • 500K+users connected by a Kafka-based matching engine
  • 35%more conversions from LLM-regenerated listing data
  • 99.9%uptime on a real-time GenAI matchmaking engine

Software Engineering Intern

Info Edge India Ltd · 99acres.com

01/2025 – 06/2025

Auth, API performance, event-driven refactors and a marketing landing page.

  • 33%higher CTA conversion from a marketing landing page I built
  • 5,000+daily logins on the OTP auth I rebuilt with Spring Security and JWT
  • 15%lower API latency through a Spring Boot API aggregator
  • 30%less duplicated code after moving approvals onto RabbitMQ

Education

B.Tech, Computer Science and Engineering

National Institute of Technology Patna

2021 – 2025

Computer science at an Institute of National Importance, with competitive programming, community leadership and an ML research project alongside.

  • 8.73CGPA out of 10
  • 1851peak LeetCode rating, Knight badge, top 5%
  • 1,200+problems solved across LeetCode and CodeChef (3-star)
  • 200+student developers in the Google Developer Student Club, as its President
  • 92%accuracy on a deep learning model for cancer-linked DNA methylation

From DSA to production

For students and engineers asking how I got here. Scroll and the path fills in.

  1. 2021Started B.Tech CSE at NIT Patna
  2. 2021 – 2025Solved 1,200+ problems. LeetCode Knight (top 5%), CodeChef 3-star
  3. At NIT PatnaPresident of the Google Developer Student Club (200+ members). Mentored Byteverse hackathon teams
  4. Jan 2025Joined 99acres as a software engineering intern
  5. Jul 2025Joined Jeevansathi as a software engineer
  6. 2026Built milanSathi, replacing a paid vendor and saving about $45,000 a year

How I work

The rules I hold myself to on every change.

Read before building
Understand the existing code and reuse its patterns before writing anything new.
Prove it, don't trust it
A replacement ships only after it's checked against the system it replaces, and against first principles where the old system is wrong.
Design before code
Agree on the approach first. Code is the cheap part once the design is right.
Add, don't rewrite
Leave working logic alone. New behaviour goes beside it, behind a flag, with a way back.

Skills

AI & LLMs
LLM orchestration (GPTGeminiQwen)LangChainLlamaIndexLangGraphRAGVector search (RedisVLChroma)MCPStructured outputsSemantic cachingEmbeddingsAgentic workflowsEvals
Backend
JavaSpring BootSpring SecurityPythonFastAPIFlaskDjango RESTNode.jsRESTMicroservices
Streaming
KafkaRabbitMQOpenfire (XMPP)Event-driven architecture
Databases
MySQLMongoDBRedisAerospikeSQLite
Infrastructure
GCPDockerKubernetesCI/CD (JenkinsGitHub ActionsGitLab CI)PrometheusGrafanaKibana
Frontend
ReactReduxJavaScript
Machine learning
PyTorchTensorFlowPandasNumPy