How We Built Tools That Scale to Millions of Lines of Code

Explore a conference talk that delves into the development of tools capable of handling millions of lines of code in Scala. Learn about innovative solutions like Taystee, Scala Meta, Semantic DB, and Metabeam, designed to tackle large-scale code analysis and manipulation. Discover how these tools contribute to improved code understanding, documentation, and refactoring capabilities. Gain insights into the evolution of Scala development tools, including Metals, ScalaFix, and experimental IntelliJ plugins. Understand the challenges and solutions involved in creating a companywide semantic index for efficient code navigation and analysis across massive codebases.

Introduction
The Problem
The Solution
Overview
Taystee
Scala Meta
Semantic DB
Text Document
Semantic DB Example
Metabeam
Symbols
Currencies
Scala Sphere in Crime
Examples
MetaDoc
MethodDoc
Metals
Metal
Code Actions
ScalaFix
Companywide Semantic Index
Experimental IntelliJ Plugin
Fabricator
Evolution
Summary
Questions