Hey! I'm Leo.

Designed a Java service for DynamoDB replication-lag computation, cutting partition-metadata reads by 90%. Streamed gzip-compressed snapshots directly to S3, reducing peak memory per upload from 480MB to ~5MB. Conducted benchmarking runs that projected a 5x latency improvement in steady-state lineage-construction.

Built a custom Go policy engine for Stripe’s tier-0 Kubernetes authorization service, cutting p99 latency by 84%. Wrote a shadow-test framework to validate authorization rules against live production traffic before deployment. Drove a canary rollout across all regions and shards with automated rollback, achieving zero post-cutover errors.

Implemented Python feature toggles with observability tooling to enable dark launches, cutting QA hours by 35%. Built end-to-end Python and Celery workflows to batch-process transfer refunds, eliminating the need for manual reconciliation.

Built a Shopify driver with Angular using a backend translation layer for integration with internal systems. Used RxJS to debounce and cache GraphQL queries, reducing network calls by 55%, and applied Angular incremental hydration to cut Cumulative Layout Shift by 30%.

Wrote Python and shell scripts to improve the internal ticketing system, reducing client response time by ~40%. Optimized cash value projections with a custom function, saving ~65 engineer hours annually.

Built and maintained data migration scripts with Prisma ORM and PostgreSQL to ensure accurate transfers. Created TypeScript interfaces and service layers for consistent backend-database communication.