Hi there 👋

I’m Andrés, a database developer with over a decade of hands-on experience building query planners and runtime engines. My work revolves around Neo4j and Vitess, and you’ll find most of my contributions right here on GitHub.

What I’m Focusing On:

• Building Neki. https://planetscale.com/blog/announcing-neki

Blogs and Papers:

• I share my thoughts on my blog
• I’ve also contributed to academic papers—check them out here.

Key Projects:

• Grouping & Aggregation Across Shards in Vitess: Brought in the Local Aggregation algorithm (inspired by this paper) to optimize shard-level aggregations across joins. Learn more
• New Query Optimizer for Vitess: Leading the charge on a new optimizer based on the GOO paper, adapted for Vitess’s sharded architecture.
• MySQL Compatibility for Vitess: Helped enhance Vitess so it behaves more like MySQL, which involved overhauls to both the planner and runtime.
• Neo4j’s Cypher Query Planner: Designed and wrote most of the inaugural Cypher planner, applying relational optimization concepts to graph queries.
• Creation of Cypher: Oversaw the specification and standardization of Neo4j’s query language, now the go-to for countless developers. Cypher Spec
• Morsel Runtime in Neo4j: Worked on the early version of Morsel, boosting query performance in Neo4j.
• Compiled Runtime for Neo4j: Part of the original development team, helping Cypher queries run faster by compiling them to bytecode.
• PlanetScale’s Boost Caching System: Designed the planner for a caching approach that transforms the plan tree into a plan DAG, allowing operators to be reused multiple times.

Achievements

• #3 contributor to Vitess and #5 contributor to Neo4j—both major open-source database systems
• My contributions have helped these projects scale to thousands of users daily, improving performance and reliability in mission-critical deployments.
• Author of influential blog posts and academic papers