V8 is Google’s open-source JavaScript engine that revolutionized JavaScript performance. Created by Lars Bak, it proved JavaScript could be fast enough for complex applications, enabling modern web development.
Origins
Google created V8 for Chrome browser, released in 2008. Lars Bak, who had worked on high-performance VMs for Java (HotSpot) and Self, led the project.
Key Innovations
V8 introduced techniques that made JavaScript fast:
- Just-in-time compilation: Compile JavaScript to machine code
- Hidden classes: Optimize property access
- Inline caching: Speed up repeated operations
- Generational garbage collection: Efficient memory management
Performance Revolution
Before V8, JavaScript was considered slow. V8 proved it could approach native speeds:
- Orders of magnitude faster than previous interpreters
- Enabled complex web applications
- Made server-side JavaScript (Node.js) viable
Beyond Browsers
V8 powers JavaScript beyond Chrome:
- Node.js: Server-side JavaScript
- Electron: Desktop applications
- Deno: Modern JavaScript runtime
- Edge: Microsoft’s browser (switched from Chakra)