Kalpesh

Freelance Software Engineer & Interview Coach

Fiverr • Freiberufler

Jan 2022 - Present • 4 yrs 9 mos

- Delivered 80+ orders for clients across the US, UAE, Saudi Arabia and other countries, keeping a 4.9★ rating and reaching Fiverr Level 2. - Built, debugged and explained programming projects in C++, Java, Python and Go: data structures, algorithms, OOP and backend services, delivered with test cases and a code walkthrough. - Designed and optimised MySQL, PostgreSQL and MongoDB databases: ER diagrams, normalisation, indexing and query tuning. - Ran 1:1 FAANG-style coding and system design mock interviews, each followed by a written scorecard and a preparation roadmap.

Gift Card Management System

Flipkart • Vollzeit

Dec 2019 - Jan 2022 • 2 yrs 1 mo

- Architected and maintained the gift card platform — issuance, activation, redemption, balance, expiry, refunds and settlement — as a high-availability, fault-tolerant service processing multiple transactions per day. - Delivered high-level and low-level designs across multiple components, and built B2C retail, B2B corporate bulk and third-party partner gift card products on one shared core. - Sharded the datastore by availability and scale requirements and ran a master-slave topology, keeping reads fast as the card base grew to 10 million active cards. - Made redemption financially safe — idempotency keys, double-spend prevention and reconciliation that keeps the ledger balanced against downstream payment systems. - Contained third-party partner failures with Hystrix circuit breakers, health checks and graceful degradation, so a partner outage never took gift card checkout down. - Moved slow work off the request path with Kafka queues, and added caching, rate limiting, proxying, logging and on-call alerting.

Clinic Management System

Jio KiviHealth • Vollzeit

Nov 2017 - Dec 2019 • 2 yrs 1 mo

Built and shipped features across the full stack of a practice-management product used daily by 10k doctors and clinic staff — appointments, patient records, prescriptions, billing and pharmacy inventory. - Designed the scheduling module, including conflict rules and calendar views, reducing double-bookings and cutting booking time by 50%. - Built pharmacy inventory with batch and expiry tracking plus reorder alerts, reducing stock-outs and expired-stock write-offs for clinics. - Implemented role-scoped access so doctors, front-desk staff and pharmacy users each see only the health data their role permits. - Owned ongoing upgrades and optimization — query tuning, refactoring and caching that kept the product responsive as clinic data grew. - Worked directly with clinic users, turning workflow complaints into shipped features — the closest thing in my career to how freelance engagements actually run.