JNJanarthanan

Janarthanan Narayanasamy

Senior Java Backend Developer · Namakkal, Tamil Nadu, India

I enjoy turning complex business needs into backends that simply work. At Astravue I build a live multi-tenant SaaS platform that stays secure and reliable.

I enjoy turning complex business needs into backends that simply work. Building a live, growing multi-tenant SaaS platform at Astravue taught me how much security, reliability and observability matter in modern backend engineering.

I work closely with product and frontend teams to shape features from idea to release. My goal isn't just to write code, but to solve problems that make the whole product faster, more resilient and easier to maintain.

LinkedInGitHubEmailResume
currently at Astravue Technologies Pvt Ltd

Impact at a glance

99.9%uptime SLAAWS, health-checked
1000sconcurrent usersmulti-tenant SaaS
−70%production downtimememory-leak & contention fix
+40%faster databasep95 latency, PostgreSQL
−50%release timeDocker + GitHub Actions
85%+test coverageJUnit 5 & Mockito
−40%post-release bugscode reviews
50+REST APIsJWT & Keycloak RBAC

About me

Role
Senior Java Backend Developer
Experience
4+ years, building production SaaS since 2022
Focus
Multi-tenant SaaS, secure REST APIs, reliability and performance
Based in
Namakkal, Tamil Nadu, India
Currently
Astravue Technologies Pvt Ltd

Tech stack

Languages
JavaJavaScriptSQL
Frameworks
Spring BootSpring MVCHibernateREST APIsWebSocketApache KafkaQuartz Scheduler
Cloud & DevOps
AWSEC2ECSS3LambdaCloudFrontCloudWatchSESSendGridDockerGitHub Actions
Security
Spring SecurityKeycloakOAuth2JWTRBAC
Database
PostgreSQLMySQLAmazon RDS
Tools & Testing
JUnit 5MockitoSwaggerPostmanNew RelicIntelliJ IDEAGit

How I build — deploy to response

A git push is built, tested and shipped to ECS; then one request travels end to end, with a trace and live log on the same clock.

Deploy
git pushGitHub Actionsbuild & testDockerECRECS
Request
CloudFrontAPI GatewayKeycloakSpring BootPostgreSQLKafka

Experience

Senior Java Developer

Apr 2022 – Present

Astravue Technologies Pvt Ltd · Chennai, India

BACKEND & ARCHITECTURE

  • Built scalable Java 17 / Spring Boot services for a multi-tenant enterprise SaaS serving thousands of concurrent users.
  • Shipped 50+ REST APIs (OpenAPI/Swagger) secured with JWT + Keycloak RBAC.
  • Improved PostgreSQL response time by ~40% through indexing, query rewrites and schema redesign.
  • Built WebSocket real-time dashboards and collaboration with sub-second latency.
  • Designed Kafka-based event-driven microservices for async processing and fault tolerance.

RELIABILITY & DEVOPS

  • Fixed memory leaks and thread contention — ~70% less production downtime.
  • Built Docker + GitHub Actions CI/CD — ~50% faster release cycles.
  • Ran services on AWS (EC2, ECS, RDS, S3, SES, CloudFront, CloudWatch, Lambda) at 99.9% uptime.
  • Kept 85%+ test coverage on critical modules with JUnit & Mockito.

LEADERSHIP

  • Led code reviews — ~40% fewer post-release bugs.
  • Mentored 3 junior developers in Spring Boot, REST API design and testing.

Featured work

Multi-Tenant SaaS Platform

Spring Boot · PostgreSQL · Keycloak · AWS ECS

One codebase serving many client companies, each fully isolated.

Read case study
Problem
Many companies had to share one platform without ever seeing each other's data.
What I built
Schema-per-tenant PostgreSQL, tenant routing on every request, Keycloak roles (RBAC) and JWT-secured REST APIs.
Result
Thousands of concurrent users on one codebase with a 99.9% uptime SLA.

Production Stability Fix

Java 17 · Heap & thread analysis · New Relic

Tracked down the memory leaks behind recurring outages.

Read case study
Problem
Memory leaks and thread contention caused repeated production incidents.
What I built
Heap and thread-dump analysis, fixes to leaking caches and lock contention, and New Relic alerts.
Result
About 70% fewer production downtime incidents.

Real-Time Notifications

WebSocket · Spring Boot · AWS SES · SendGrid

Live changes and alerts reach users instantly, in the app and by email.

Read case study
Problem
Users had to refresh to see changes, and important events were easy to miss.
What I built
WebSocket push for live dashboards and in-app notifications, plus email notifications through AWS SES and SendGrid.
Result
Sub-second live updates, and every important event reaches users both in the app and in their inbox.

CI/CD & Faster Releases

Docker · GitHub Actions · AWS ECS · JUnit 5

Every push built, tested and shipped automatically.

Read case study
Problem
Manual, slow releases with bugs found late.
What I built
A build → test → Docker → deploy pipeline with an 85%+ coverage gate and rolling deploys to ECS.
Result
About 50% faster release cycles and fewer post-release bugs.

Monitoring & Observability

New Relic APM · CloudWatch · Structured logs · Actuator

Problems are spotted and traced before users feel them.

Read case study
Problem
Slowdowns and errors were often found by users first, and hard to trace back to a cause.
What I built
New Relic APM on every service, structured logs with request IDs, Spring Boot Actuator health checks, and CloudWatch dashboards and alarms for latency, errors and memory.
Result
Issues are caught and traced quickly, which fed directly into the 70% drop in production downtime.

Database Performance

PostgreSQL · Indexing · Query tuning · Hibernate

Kept the database fast while tenant data kept growing.

Read case study
Problem
Some pages and APIs slowed down as the amount of tenant data grew.
What I built
Found the slowest queries, added the right indexes, rewrote heavy queries and redesigned parts of the schema.
Result
About 40% faster PostgreSQL response times.

GitHub activity

Most of my work lives in private company repositories, so this shows only part of it.

Education

Bachelor of Science (B.Sc)

2016 – 2018

Jairam Arts and Science College, Salem