Vert.x

Reactive applications on the JVM

★ 4.3

Reactive toolkit for building distributed systems on the JVM. Event-driven, non-blocking with polyglot support for Java, Kotlin, Scala, Groovy, and JavaScript.

14K

GitHub Stars

none

TypeScript

steep

Learning Curve

4.0

DX Score

Visit Website → Documentation GitHub

Pricing

Model

free

Free Tier

Apache 2.0 / Eclipse licensed, open source

Paid

N/A

Features

✓ Event-driven
✓ Non-blocking IO
✓ Polyglot support
✓ Event bus
✓ High concurrency
✓ Clustering
✓ Service discovery
✓ Circuit breaker

Pros

+ Exceptional performance
+ Multi-language support
+ Low resource usage
+ Distributed by design
+ Flexible toolkit

Cons

- Reactive learning curve
- Callback complexity
- Less structured
- Fewer tutorials

Best For

enterprise startup

Alternatives

Quarkus

reactive event-driven high-performance polyglot