-
InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
Depends what you want to learn. If web development, The Odin Project is what everyone recommends and I can recommend it as well.
The Rust Book is a great free resource which I recently used to learn Rust
NOTE:
The number of mentions on this list indicates mentions on common posts plus user suggested alternatives.
Hence, a higher number means a more popular project.