Senior Software Engineer — Java Backend & Distributed Systems

Ankit Kumar
Srivastava

I build payment infrastructure and distributed systems that hold up under real traffic — in Java, at scale, under compliance.

4+ years shipping production systems at Zeta Tech, Netcore Cloud, and Zscaler — PCI-DSS payment pipelines, Kafka-driven microservices, and Kubernetes at scale. Currently exploring AI/LLM engineering with Spring AI, RAG, and MCP, and open to my next role.

01

About

A Java backend engineer building payment infrastructure and distributed systems — now branching into AI/LLM engineering.

I'm a Computer Science graduate from Galgotias College Of Engineering And Technology, Greater Noida, with 4+ years of professional experience building production systems on Spring Boot, Kafka, and Kubernetes inside PCI‑DSS regulated environments — from rebuilding core payment-transaction services to designing microservices architecture with product and platform teams.

I've led a cross-functional team of five, cut latency, cost, and reconciliation time by 20–40%, modernized CI/CD pipelines with Jenkins and GitHub Actions, and secured 20M+ cardholder records in compliance-regulated pipelines. I mentor engineers as a matter of habit — 500+ students and counting.

Right now I'm exploring AI/LLM engineering — Spring AI, LangChain, RAG, MCP — and looking for my next role building reliable systems that create real value at scale.

Years experience
0
Records secured
0
Teams led / mentored
0
Current focus
AI / RAG
02

Experience

  1. Mar 2025 — Jun 2026 Mumbai, India

    Zeta Tech (Directi)

    Software Development Engineer — Java Backend

    • Rebuilt core payment-transaction services in Java and Spring Boot, backed by JUnit/Mockito test suites, cutting critical API response times by 30%.
    • Co-designed the payments microservices architecture with product and platform teams, reducing operational overhead by 40%.
    • Built PCI-DSS compliant data pipelines in Java processing 20M+ cardholder records, cutting batch reconciliation time from 6 hours to 2 in coordination with the compliance team.
    • Introduced Kafka event streaming and Redis caching in the core transaction path, cutting latency by 20% and database load by 35%.
    • Deployed and monitored Spring Boot services on Kubernetes with ELK-based observability, reducing infrastructure costs by 20%.

    Java · Spring Boot · JUnit/Mockito · Kafka · Redis · Kubernetes · ELK Stack · PCI-DSS

  2. Feb 2023 — Mar 2025 Mumbai, India

    Netcore Cloud

    Software Engineer — Java Backend

    • Led a cross-functional team of five building Java and Spring Boot microservices, owning sprint planning, code reviews, and releases — cut downtime by 40%.
    • Tuned SQL queries and Hibernate/JPA mappings across core services, boosting application performance by 30%.
    • Set up Maven-based CI/CD pipelines with Jenkins and GitHub Actions, cutting deployment time by 50%.
    • Integrated OAuth 2.0 and JWT-based authentication into the Java backend, cutting average authentication time from 5s to 2s.

    Java · Spring Boot · Hibernate/JPA · Maven · Jenkins · GitHub Actions · OAuth 2.0 · JWT

  3. Jan 2022 — Aug 2022 Chandigarh, Mohali, India

    Zscaler

    Software Engineer Intern

    • Executed core components of a legacy-to-cloud migration, improving access speed by 40% for 100+ users with minimal downtime.
    • Designed encryption methods and 100+ test scenarios with the QA/security team, achieving a 99% success rate securing data for 200+ users.

    Python · Shell Scripting · Selenium · Pytest · AWS

  4. Jul 2021 — Jan 2022 Delhi, India

    Sunrise Mentors Pvt. Ltd.

    Teaching Assistant, EdTech Platform

    • Mentored 500+ students and led a 15-member TA team across 25 web development projects, standardizing code-review feedback.

    Python · Java · C++ · Web Development · Mentorship

03

Projects

Flagship work in data engineering, backend systems, and enterprise AI — the rest is one scroll further down.

FocusTodo collaborative todo app interface

FocusTodo Collab Todos

Full-stack todo app with shareable realtime rooms — REST for CRUD, STOMP/WebSocket for live sync.

  • Excalidraw-style share links so multiple browsers edit the same list live.
  • Optimistic locking via @Version (409 on conflict) so concurrent edits don't silently overwrite.
  • One-command local run with Docker Compose, plus Postman collection and Swagger UI.

Java 21 · Spring Boot 3 · React (Vite) · MongoDB · STOMP/SockJS · Docker Compose

View source ↗
Real-Time UPI Analytics Platform dashboard

Real-Time UPI Analytics Platform

Production-grade, end-to-end data engineering pipeline for real-time UPI transaction analytics.

  • Kafka ingestion with Flink for real-time validation and cleaning.
  • dbt transformation models plus Airflow DAGs for daily batch aggregations.
  • Grafana dashboards for real-time visualization, fully containerized with Docker Compose.

Kafka · Flink (Java) · Airflow · PostgreSQL · dbt · Grafana · Python · Docker

View source ↗
Enterprise RAG Intelligence Platform interface

Enterprise RAG Intelligence Platform

Plug-and-play enterprise AI assistant with config-driven RBAC, hybrid retrieval, and knowledge graph reasoning.

  • Hybrid retrieval — dense (BGE + Qdrant) and sparse (BM25 + Elasticsearch) — with cross-encoder reranking.
  • Retrieval-time role filtering and PII/secret blocking for unauthorized roles.
  • Knowledge-graph multi-hop reasoning with NetworkX; JWT auth, audit logs, RAGAS eval, Langfuse/Phoenix tracing.

FastAPI · Streamlit · Qdrant · Elasticsearch · BGE Embeddings · NetworkX · Docker

View source ↗
PII Masking API architecture diagram

PII Masking API Go

Stateless Go microservice masking PAN, Aadhaar, phone, email, and GSTIN before logs or downstream systems see raw data.

  • Single mask, bulk mask, validate-only, and auto-detect endpoints.
  • Format validation before masking — invalid input returns 400, not partial leaks.
  • Stateless, no database dependency — runs behind a gateway or as a sidecar.

Go · net/http · Docker · Regex validation

View source ↗
PDF Toolbox API screenshot

PDF Toolbox API Go

Production Go microservice for merge, split, compress, encrypt, and convert — outputs land on Cloudflare R2 with a public URL.

  • Multi-endpoint processing: merge, split, compress, encrypt/decrypt, doc-to-PDF.
  • Containerized with qpdf, ghostscript, poppler-utils, and LibreOffice.
  • Deployed on Railway with environment-aware config.

Go · pdfcpu · qpdf · LibreOffice · Docker · Cloudflare R2 · Railway

View source ↗

Also built

04

Skills

Languages

JavaGoPythonC/C++JavaScriptPHPC#

Frameworks

Spring BootHibernate/JPAGuiceGinFlaskDjangoExpress.jsNode.jsReact.jsAngularJS

Testing & Build

JUnitMockitoMavenGradlepytestJestGoogleTestnpm

Cloud & DevOps

AWSDockerKubernetesTerraformHelmArgoCDGit / CI-CDIstio

Data Engineering & Messaging

KafkaRabbitMQAmazon SQSApache AirflowApache FlinkApache SparkdbtSnowflake

Databases

PostgreSQLMySQLMongoDBRedisVertica

Observability & Security

ELK StackPrometheusGrafanaOpenTelemetryOAuth 2.0JWTRBACSnykSonarQube

Architecture & Design

Distributed SystemsMicroservicesEvent-Driven ArchitectureREST APIsHLD/LLDOOPDesign PatternsCamunda BPMNLinux

AI & LLM Engineering

Spring AILangChainOpenAI APIAnthropic Claude APIGemini APIRAGQdrantpgvectorMCPCursor
05

Achievements

Competitive programming credentials — because algorithmic muscle memory still matters at 2am during an incident.

Top 1%

94th of 10,000+ finishers — Credit Suisse Global Coding Challenge.

954th

Global rank — Google Code Jam, among worldwide competitive programmers.

1816

Codeforces max rating — 780th (Div. 2 Round 720) and 402nd (Div. 2 Round 728).

06

Education

Galgotias College Of Engineering And Technology

Greater Noida, India · B.Tech, Computer Science & Engineering · Aug 2018 — Jul 2022 · CGPA 8.76/10

Data Structures & Algorithms · Database Management Systems · Operating Systems · Machine Learning · Digital Image Processing

ISC Board

Senior High School · PCM (Science) · 89.25%

Physics · Chemistry · Mathematics

07

Contact

Open to backend and distributed systems roles — reach out directly.

Elsewhere: Medium GeeksforGeeks LeetCode Codeforces CodeChef HackerRank HackerEarth