Zorawar Sachdev

Investigated distributed systems end-to-end; identified major debt and proposed refactors: Lagom, Akka → Pekko; functional stack (Cats Effect, FS2) and Kafka → AWS Kinesis. Addressed issues including weak idempotency, inconsistent strong consistency, multi-tenant fragmentation, rising costs from over-provisioning and heavy Akka usage. Proposed architectural redesign, multi-tenancy, Dead Letter Queues, batching, and reusable domain components; highlighted security gaps such as unauthenticated endpoints and unvalidated webhooks.

Orchestrated Airflow-based workflows to increase fault tolerance, handling external failures due to 3rd-party downtimes by automating retries; authored extensive unit, integration and regression tests; supported tracing and monitoring on dashboards; evolved data pipelines for real-time streaming and automated monthly finance reports; assisted a critical database migration (MariaDB→ Cassandra) and the migration of services from on-prem to GCP.

Spearheaded backend initiatives for 300M+ daily active users; built an in-house payments solution to reduce app-store fees and boost ARPU; designed microservices for payments and subscription lifecycle; implemented an event-driven architecture with high-throughput messaging and multiple gateways. Led data processing pipelines, database migrations (MariaDB → Cassandra) and cloud migration to GCP; performed code refactors (Java→Scala, DropWizard→Play, Scala 2→3, HTTP→gRPC) and moved toward a more functional style.