Łukasz Jancewicz presented Google Cloud’s enormous Angular application, encompassing 15 million lines of code, alongside its distinctive MicroFrontend setup. A newly published RFC on Incremental Hydration grants finer-grained authority over hydration processes within server-side rendered applications. Starting with Angular 19, the default for `standalone: true` will apply unless devs deliberately override it with `false`, and there’s tooling to handle the migration automatically.
Largest Angular App
Łukasz Jancewicz appeared as a guest on the Angular Masters Podcast, hosted by Dariusz Kalbarczyk. As an employee at Google Cloud, Łukasz works on an Angular application of massive proportions—its codebase totals 15 million lines. That platform is currently maintained by 2,000 engineers.
During the conversation, Łukasz highlighted the scalability hurdles they encounter, with a particular focus on rolling out features that cut across the platform's horizontal layers.
Their complete codebase lives within Google's mono repository, yet they rely on a MicroFrontend design. This setup is entirely proprietary and depends on two iFrames: one that hosts the App Shell, and another dedicated to the MicroFrontend itself.
Their architecture includes a clever mechanism where they modify the MicroFrontend iFrame so calls to DOM manipulation methods get executed within the App Shell's designated placeholder for the MicroFrontend, which keeps everything coordinated and consistent.
Łukasz also delved into their testing practices. For a system with this much complexity, testing is a major priority, as you would expect.
Additionally, the team undertook a migration from AngularJS to Angular. Automation handled a significant portion of that transition, but the full transformation still demanded five years to complete.
Incremental Hydration
The feature previously referred to as Progressive Hydration has been rebranded as Incremental Hydration, with the corresponding RFC now live.
In Server-Side Rendering (SSR), the client gets the static markup right away, then Angular loads afterwards. This sequence is called Hydration.
With Incremental Hydration, existing defer blocks and their associated dependencies can skip the initial hydration pass. You can set triggers like "on interactive" or "on timeout" to postpone hydration, so the deferred view’s content is visible right away but stays inert until that trigger fires. In the past, defer functioned like a lazy-loaded component; now Incremental Hydration takes it far beyond that.
What’s more, there’s also the capability to bypass hydration for a deferred view entirely if you so choose.
The RFC is now open for comments and input, inviting the community to share their perspectives.
https://github.com/angular/angular/discussions/57664
The Future is Standalone
Alex Rickabaugh, the Angular framework lead, authored the piece "The Future is Standalone," laying out promising enhancements for Angular 19. A headline alteration concerns the standalone property’s behavior.
From now on, an absent standalone property will default to true automatically. As a result, you can confidently strip out every occurrence of standalone: true from your components. Conversely, you’ll have to explicitly set standalone: false if you wish a component to be non-standalone.
Beyond that, a tsconfig option will be introduced to let the compiler prohibit standalone components entirely if you prefer.
As is typical, Angular’s update tooling will handle this migration automatically, ensuring a smooth transition with no manual work required.
Detective
A novel architectural analysis tool named Detective has been rolled out by Manfred Steyer. It offers visual aids to help developers gain clearer insights and evaluate their application’s structure. He’s also released a companion blog post diving into effective usage guidelines for the tool.
angulararchitects.io
Angular Developer Survey
In other news, Matthieu Riegler has officially opened the annual Angular Developer Survey. If you get a chance, do take part—responses from earlier editions have proven highly influential in steering the framework's roadmap.