Scala Logging Libraries
Scala logging libraries leverage the fusion of functional programming and JVM ecosystem. scala-logging, Scribe, Log4s, and others provide type safety, pure functional approaches, and JVM library interoperability.
Key Features
- Multiple Output Levels
- Structured Logging
- High Performance
- Multiple Output Destinations
- Rich Ecosystem
Representative Libraries
- Pino: Ultra-fast JSON logging library
- Winston: Most versatile logging library
- Bunyan: Structured JSON-focused logging library
- Morgan: Express.js HTTP logging middleware
GitHub Star Comparison
| No | Name | GitHub Stars | Description | Trend | License | Type | Official Site |
|---|---|---|---|---|---|---|---|
| 1 | Scala-Logging | - | Convenient and performant Scala logging library wrapping SLF4J. Maintained by Lightbend Labs with idiomatic API design leveraging Scala characteristics. Built on top of SLF4J and other logging libraries, most widely used Scala logging solution. | Established position as most popular choice in Scala ecosystem for 2025. Standard adoption in enterprise-level Scala projects due to Lightbend's continuous support and excellent compatibility with existing JVM logging infrastructure. | Apache-2.0 | Idiomatic Logger | Official |
| 2 | Scribe | - | Logging framework claiming to be fastest on JVM. Built from scratch in Scala with programmatic configuration capabilities. Not wrapper around traditional Java logging frameworks, achieves compile-time optimization through macros. Supports real-time configuration changes. | Adoption expanding in Scala applications where performance is paramount in 2025. Achieves performance surpassing traditional Java-based solutions through pure Scala implementation and macro-based optimization. Selection examples increasing in high-load systems. | MIT | High-performance Logger | Official |
| 3 | Log4s | - | High-performance Scala wrapper for SLF4J. Leverages Scala's macros and value classes to provide idiomatic Scala facade without imposing runtime overhead. Frequently outperforms common usage patterns of JVM APIs. | Adoption continues in projects seeking both performance and Scala-like characteristics in 2025. Provides Scala convenience without compromising runtime performance through compile-time optimization. Has track record in medium to large-scale projects. | Apache-2.0 | Macro-optimized Logger | Official |
| 4 | SLF4J + Logback | - | Traditional combination popular in Scala applications. SLF4J solves logging abstraction problem over different JVM frameworks, while Logback and Log4j 2 provide flexibility and powerful features. High track record and reliability in Scala community. | Adoption continues in conservative Scala projects and existing systems in 2025. This proven combination selected particularly in enterprise environments where integration with Java ecosystem is important. Trend toward prioritizing Scala-specific solutions in new projects. | MIT | Java Ecosystem | Official |
| 5 | ScalaLogging (Alternative) | - | Alternative implementation of Scala logging library built on top of SLF4J. Focuses on basic functionality with emphasis on lightweight nature. Provides simpler API and minimal dependencies through different approach from scala-logging. | Selection examples seen in Scala projects prioritizing lightweight nature in 2025. Adoption in scenarios requiring only basic logging functionality without complex features. However, tends to be inferior to scala-logging in community support and maintenance frequency. | Apache-2.0 | Minimal Logger | Official |
| 6 | println() (Built-in) | - | Scala's standard output function. Suitable for rapid log output in learning stages and quick debugging as simplest debugging means. Immediately available without configuration, but has feature limitations in full-scale application development. | Usage continues in early stages of Scala learning and experimental code verification in REPL in 2025. However, migration to structured logging libraries strongly recommended for full-scale Scala application development. Println remnants in production code recognized as quality issue. | Apache-2.0 | Native Function | Official |