SDE Backend · Apr 2023 – Jul 2025
JAR
Gold-tech fintech. Microservices from scratch, payouts, referrals, KYC for 30 million users, and the Premier League leaderboard that moved GMV.
Payout save
₹18M / yr
KYC
30M users
Problem
Consumer gold at scale: partners, payouts, acquisition cost, and festival-scale contests. The backend had to be boringly reliable.
What I built
- Three microservices from scratch: FY transactions, B2B partners, internal CRM
- Payout-partner migration that saved ₹18 million a year
- Referrals → gamification, cutting monthly acquisition cost by ₹5 million
- JAR Premier League leaderboard on Redis, +3% monthly GMV
- KYC with hybrid encryption for 30 million users
- Gold sell / withdrawal revamp; 50+ A/B tests; 15+ features from scratch
Architecture
Java services on AWS, Redis for hot paths (leaderboard, sessions), Postgres/Mongo for source of truth, Unleash for experiments.
JavaSpring BootRedisAWSPostgresMongoDB