Seed Zeng

I lead the team and own the technical direction for DoorDash's Storage org — the data infrastructure the whole company runs on.

• –Lead and grow a 40-engineer organization — mentoring and developing staff and senior engineers into the next layer of technical leaders.
• –Set vision and roadmap for the core initiatives redefining the storage layer, partnering across product and infra teams.
• –Own the online datastore platform every product team builds on — accountable for reliability, performance, and long-term architecture behind millions of orders a day.

Made DoorDash's core storage faster and cheaper as the business scaled globally.

• –Drove fleet-wide efficiency and performance gains across the Cassandra deployment (“Cassandra Unleashed”).
• –Mentored engineers and raised the technical bar across the team.
• –Scaled core storage infrastructure to keep pace with global growth.

Tech-led data-integrity systems for Meta's distributed infrastructure.

• –Built inconsistency-detection services for large distributed systems using novel techniques.
• –Scaled complex backend services to absorb major traffic spikes.
• –Mentored engineers and helped them grow.

Re-architected Klaviyo's data ingestion and scaled it ~300×.

• –Built Abacus 2.0 — a full overhaul of the ingestion model, read API, and schema — ~10× faster than its predecessor.
• –Scaled the pipeline from 500 to 150,000 events/sec (3M DB writes/sec), built to scale horizontally.
• –Wrote the migration service that moved production data onto the new schema.

Built the streaming foundations Klaviyo's data platform still runs on.

• –Built Abacus 1.0 on Apache Flink, replacing the legacy ingestion pipeline — 1.5B events on Cyber Monday alone.
• –Built Klaviyo’s first Kafka microservice, now handling billions of events a day.
• –Maintained core data stores (MySQL, Cassandra, Redis, Memcache) and refactored the legacy pipeline to clean OOP.

Backend engineer across survey infrastructure and AWS data systems.

• –Built survey-branching logic that adapts each next question to user input.
• –Improved AWS scalability and led a migration from Postgres to DynamoDB.