ArcticDB

It is an embeddable columnar database written in Go. It features semi-structured schemas (could also be described as typed wide-columns), and uses Apache Parquet for storage, and Apache Arrow at query time. It provides a query builder and various optimizers (it reminds of DataFrame-like APIs).

ArcticDB is a tool in the Databases category of a tech stack.

ArcticDB is an open source tool with GitHub stars and GitHub forks. Here’s a link to ArcticDB's open source repository on GitHub