Rails 8 brings a bundle of enhancements across performance, developer experience, infrastructure, and modern web app capabilities. Below are the top features you should know about.

1. Modern Asset Pipeline: Propshaft

Rails 8 replaces the long-standing Sprockets asset pipeline with Propshaft, offering a streamlined, modern approach to managing JS, CSS and images. BlueBash portfolio+3Mintbit+3AppSignal Blog+3

Why it matters:

1. Faster asset compilation and simpler configuration.
2. Better compatibility with modern frontend tooling (ESBuild, import maps).
3. Reduced complexity when upgrading or maintaining Rails apps.

2. Reduced Infrastructure Dependencies: The “Solid” Adapters

One of Rails 8’s most talked-about improvements is the introduction of built-in adapters for caching, job queues and WebSocket pub/sub — namely Solid Cache, Solid Queue and Solid Cable. DEV Community+2AppSignal Blog+2

Why it matters:

1. You can now reduce or eliminate the need for external services like Redis or Memcached for many apps.
2. Simplifies deployment, especially for smaller or mid-scale apps.
3. Improves maintainability and lowers cost for infrastructure.

3. Built-in Authentication Generator

Rails 8 introduces a native authentication generator that scaffolds user models, controllers, and sessions without the need to pull in heavy third-party gems like Devise for basic use-cases. Mintbit+1

Why it matters:

1. Faster set-up for apps that need standard email/password login flows.
2. Less “glue” code required; faster to get up and running.
3. Still extensible if you need advanced auth later.

4. Improved Performance & Asynchronous Capabilities

Rails 8 enhances how ActiveRecord and the framework handle large datasets, async queries and multi-threaded environments. Nikita Sinenko+1

Why it matters:

1. Better handling of heavy workloads or real-time features.
2. Async query methods, more efficient job handling and optimized memory usage.
3. Feels more responsive for end-users and more scalable as your usage grows.

5. Enhanced Support for Progressive Web Apps (PWA) & Hotwire Integration

Rails 8 deepens its support for real-time/web-app features, including improved integration with the Hotwire stack (Turbo, Stimulus) and better default support for PWAs. Mintbit+1

Why it matters:

1. Build nearly full-featured web/mobile experiences with fewer dependencies.
2. Improved offline/offline-first capabilities, notifications, real-time UI.
3. Great for startups or new apps that want modern behavior out-of-the-box.

6. Simplified Deployment Experience: Kamal + Zero-Downtime Integration

Rails 8 includes the ability to deploy in simpler ways, with built-in support for production setups and zero-downtime deployment workflows. AppSignal Blog+1

Why it matters:

1. Less infrastructure-overhead for getting a Rails app into production.
2. Helps teams move faster from development → staging → production.
3. Good for startups or small teams wanting Rails speed without massive ops overhead.

Should You Upgrade to Rails 8?

Short answer: Yes — if you’re working on a new app, or you have an existing Rails app and want to take advantage of modern best practices, simplicity and performance improvements.

Things to consider:

1. Check compatibility of your gems/plugins with Rails 8.
2. For older apps with complex migration paths, factor in some upgrade effort.
3. Use the newer features when they make sense (you don’t have to switch everything at once).
4. Prioritize the features you’ll benefit from most (e.g., if you rely on external services heavily, the “Solid” adapters may shift how you think about infrastructure).

Final Thoughts

Rails 8 is more than just incremental — it represents a renewal of the Rails philosophy: keep things simple, elegant, and developer-friendly, while adapting to modern web app demands. Whether you’re building a startup MVP or maintaining an enterprise system, these new features offer real value worth exploring.