Over the summer, we were blessed with new versions of Flutter and Dart. Today, we’ll also shine a light on component separation and a pretty significant step forward in code generation.
So let’s get to it.
Flutter 3.35 & Dart 3.9
The new version Flutter comes with improvements that will potentially save several years of our lifespan. Flutter Web finally received Hot Reload, which means you can now observe changes in the code immediately without restarting the application.
On Android, the SensitiveContent widget has been added, making it easy to hide sensitive parts of the screen when sharing or uploading videos. The core and Impeller rendering engine have also been improved, resulting in faster application launches and better graphics performance. iOS compatibility has also been extended to include new versions of Xcode and features such as Live Text. And to top it off, Flutter has officially integrated the MCP server for collaboration with AI assistants, who are now way sharper and quicker to grasp your entire project.
We also got the long-awaited Flutter Widget Previewer. It’s an experimental tool that greatly simplifies working with UI. From now on, you can generate a preview of any widget using the @Preview annotation, and it will immediately render in a separate Chrome window, completely outside the normal application. Changes are then updated with Hot Reload during debugging, so testing UI components (for example, across different sizes, themes, or text-scale factors) is now remotely accessible and extremely fast. This feature is still experimental—the API may change—but it allows for much more convenient iteration and separation of the UI from the logic of the entire project.
Meanwhile, Dart has seen major updates in security and performance. Starting with null safety, which detects more errors during code analysis and fixes a long-known weakness in types returned from getters. Tools such as dart analyze or dart format also load noticeably faster thanks to the new AOT execution, and that’s something we’ve been noticing daily since then.
Dependency management has also received a boost. It’s now possible to filter packages imported via git using git tags, with support for custom tag formats as long as they contain a version number. Like Flutter, Dart now has stable support for the MCP server, so AI assistants can offer smarter suggestions and solutions directly within the development environment.
Material a Cupertino decoupling
In the last FFN, we mentioned that separation of Material and Cupertino into individual components could be imminent. Our prayers have finally been answered: The Flutter team will actively work on splitting them into separate libraries. At it’s core, Flutter will become more comprehensive and provide universal basic widgets.
See Umbrella Issue #101479 for more details.
But we’ll have to wait a bit, likely until 2026 at the earliest.
A new record for Build_runner
Build_runner is a tool for generating code in Dart/Flutter projects. Its reputation is less than glowing, mostly because of its slowness. However, recent weeks have brought major optimizations.
After the removal of macros, work’s been underway to speed up and optimize the build_runner library for code generation. David Morgan (https://x.com/__davidmorgan__) has been particularly active in this area, and we owe him a big thanks.
https://x.com/tenhobi/status/1935608371559932156
Following its first update, which is definitely not the last, we are seeing a roughly 10x speedup on projects, from 105 to 12 seconds. That's a decent upgrade. Not under 1 second, which would be perfect for us, but we'll keep wishing for it in a future update.
One of the other things discussed is AOT compilation of builders, which could bring further performance gains. This requires a few more changes, such as stopping the use of dart:mirrors in the source_gen package. Sounds like a small price to pay for faster generation, so we're all for it.
https://x.com/__davidmorgan__/status/1955919090985447511
Until next time! ⏲️
