PumpkinDB vs RethinkDB: What are the differences?

Developers describe PumpkinDB as "An event sourcing database engine *". PumpkinDB is a compact event sourcing database engine, featuring fast on-disk storage, flexible approach to event structure and encoding, sophisticated event indexing and querying. On the other hand, *RethinkDB** is detailed as "JSON. Scales to multiple machines with very little effort. Open source". RethinkDB is built to store JSON documents, and scale to multiple machines with very little effort. It has a pleasant query language that supports really useful queries like table joins and group by, and is easy to setup and learn.

PumpkinDB and RethinkDB can be primarily classified as "Databases" tools.

Some of the features offered by PumpkinDB are:

• Fast file-based storage
• Library of building primitives: encoding, indexing, subscriptions, etc.
• Query language that compiles to PumpkinScript

On the other hand, RethinkDB provides the following key features:

• JSON data model and immediate consistency.
• Distributed joins, subqueries, aggregation, atomic updates.
• Secondary, compound, and arbitrarily computed indexes.

PumpkinDB and RethinkDB are both open source tools. RethinkDB with 22.4K GitHub stars and 1.74K forks on GitHub appears to be more popular than PumpkinDB with 1.11K GitHub stars and 48 GitHub forks.