Hi, I am Karthik Kulkarni

ENGINEERING
SYSTEMS OF
HIGH DENSITY_

2 yrs 8 mos building high-volume payment systems at HCLTech[Citi]. Spring Boot, Kafka, event-driven microservices. Currently architecting a 10-repository banking platform with a transactional outbox.

You design. I build the backend.

↓ Jump to work See the work →Get in touch

Role: Senior Software Engineer @ HCLTech[Citi]
Focus: Distributed Payment Systems
Location: Bengaluru, IN
Status: Open_To_Opportunities

Java 17
Spring Boot
Spring Cloud
Spring Security
Apache Kafka
MongoDB
MySQL
Docker
Keycloak
Redis
REST
JUnit

// Signal.log

What 2 yrs 8 mos at HCLTech [Citi]
actually moved.

Numbers reflect owned scope on the APAC Payment Acceptance System — real SLAs, real reconciliation, real deploys.

01 · HCLTech · Citi

2y 8m

Production experience

02 · Cross-border payments

APAC

Region

03 · PAS pipeline

Per-txn SLA held

04 · Payer ID service

85%

Faster onboarding

05 · Multi-country validation

80%

Less reconciliation

06 · 4 quarterly releases

Prod defects

Selected_Modules.log

All work →

[ 01 ]

Arya Banking

Event-driven banking platform — 14 repositories, 6 Spring Boot services with Kafka-based async communication, a multi-module shared library (core, mongo, kafka, feign, oauth2), a BOM for centralized dependency management, a transactional outbox starter library, Avro schemas on Confluent Schema Registry, Keycloak IAM, Vault secrets, MongoDB persistence, and Spring AOP for cross-cutting concerns. Includes a 100+ page documentation site.

Spring BootKafkaOutbox PatternAvroKeycloakVaultMongoDBDockerMicroservicesSpring AOP

Spring Boot Microservices Banking

Microservices banking platform with Eureka service registry, Spring Cloud Gateway, Keycloak auth, and Feign Client communication. Database-per-service pattern with 5 dedicated MySQL instances.

Spring BootMicroservicesEurekaKeycloakMySQL

MODULE_SB_MICROSERVICES↗

Stars

Forks

/Now

Updated Q3 2026

01
Architecting a 10-repository event-driven banking platform — Kafka, transactional outbox, Avro schemas, Spring AOP, and a live 100+ page docs site.
02
Sharpening system design fundamentals — CAP, backpressure, idempotent consumers.
03
Writing long-form on Kafka, Spring Batch, and microservice communication.
04
Open to senior backend roles — remote or Bengaluru.

// Field_Notes.txt

Owns problems end-to-end. Ships production-grade Kafka pipelines without hand-holding.
— Tech Lead · Citi / APAC Payments

Turns vague compliance requirements into clean service boundaries. Rare skill.
— Product Manager · Payments