# Networking & VPN > Selected Engineer ApS work demonstrating Networking & VPN — the achievements that prove it. - [Designed, implemented, and administered 6 ETL/ELT pipelines, utilizing Google BigQuery, MSSQL, PostgreSQL, Shell scripting, PL/pgSQL, and Transact‑SQL, integrating data for efficient Python API processing.](https://software.engineer.company/portfolio/designed-implemented-and-administered-6-etl-elt-pipelines-8/) - [Built fail‑closed abuse controls — 22 Redis‑backed rate limiters, Cloudflare Turnstile, request idempotency and an origin lock — so the platform sheds bots and floods instead of trusting its callers.](https://software.engineer.company/portfolio/built-fail-closed-abuse-controls-and-rate-limiting-100/)