intermediate

Refactoring Techniques in Scala

This course path teaches developers to enhance challenging codebases with safe, incremental changes. It covers dependency breaking, refactoring, and characterization testing to modernize existing systems while maintaining functionality.

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Verified skills you'll gain

INTERMEDIATE

Computer Systems and Architecture

ADVANCED

Software Development Practices

Tools you'll use

Mockito

Scala

ScalaTest

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Course 2

Breaking Dependencies to Improve Code

4 lessons

20 practices

Breaking dependencies is crucial in existing systems to make them more testable, maintainable, and extensible. By reducing coupling and isolating functionality, developers can introduce changes incrementally while minimizing risks. In this course we focus on removing coupling with traits and dependency injection techniques for testability.

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Course 3

Using Seams to Enable Testability and Expand Capabilities

4 lessons

18 practices

Seams are strategic points in code where behavior can be modified without altering the existing implementation. They are crucial for introducing changes safely, enabling testing, and incrementally refactoring legacy systems. This course explores functional and object seams and their role in improving code maintainability in Scala.

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Course 4

Using Sprout and Wrap Techniques

6 lessons

27 practices

Sprout and wrap techniques help safely add or modify functionality in existing code by introducing new methods, classes, or wrappers. These approaches minimize risk, preserve legacy behavior, and improve testability. This course covers both techniques for refactoring and expanding Scala code.

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From our community

Hear what our customers have to say about CodeSignal Learn

I'm impressed by the quality and can't stop recommending it. It's also a lot of fun!

Francisco Aguilar Meléndez

Data Scientist

+11

I love that it's personalized. When I'm stuck, I don't have to hope my Google searches come out successful. The AI mentor Cosmo knows exactly what I need.

Faith Yim

Software Engineer

+14

It's an amazing product and exceeded my expectations, helping me prepare for my job interviews. Hands-on learning requires you to actually know what you are doing.

Alex Bush

Full Stack Engineer

I'm really impressed by the AI tutor Cosmo's feedback about my code. It's honestly kind of insane to me that it's so targeted and specific.

Abbey Helterbran

Tech consultant

I tried Leetcode but it was too disorganized. CodeSignal covers all the topics I'm interested in and is way more structured.

Jonathan Miller

Senior Machine Learning Engineer

+12

I'm impressed by the quality and can't stop recommending it. It's also a lot of fun!

Francisco Aguilar Meléndez

Data Scientist

+11