Lucid Icons version is no longer supported

[dedan-zeraki]

Describe the bug
Running the app on the latest flutter version on iOS throws the error below:

    ../../../../.pub-cache/hosted/pub.dev/lucide_icons-0.257.0/lib/src/icon_data.dart:3:30: Error: The class 'IconData' can't be extended outside of its library because it's a final class.
    class LucideIconData extends IconData {
                                 ^
    Target kernel_snapshot_program failed: Exception
    Failed to package /Users/dedan/DEV/projects/mostro/mobile.

To Reproduce
Steps to reproduce the behavior:

1. Update to the latest Flutter version.
2. Run the app
3. The build fails and the error pops up.

There's an up to date replacement which works: flutter_lucide.
I would be happy to action it.

[Pivii]

I tried to reproduce this while establishing an iOS build baseline (#80) and could not, on either the version the repo pins or current stable.

The error quoted here requires IconData to be a final class. It is not, in either version I checked:

# Flutter 3.35.7 (what .fvmrc declares)
$ sed -n '22,24p' packages/flutter/lib/src/widgets/icon_data.dart
@immutable
class IconData {

# Flutter 3.41.2 (stable)
$ sed -n '22,24p' packages/flutter/lib/src/widgets/icon_data.dart
@immutable
class IconData {

@immutable, not final, so class LucideIconData extends IconData compiles. A full flutter build ios at main = v1.4.2 on Flutter 3.35.7 succeeds with lucide_icons: ^0.257.0 untouched — simulator and device-release, no packaging error.

My guess is that this was hit on a beta or master build where IconData had been made final, and that the change was reverted before it reached stable. If that is right, this issue is not currently reproducible and could be closed.

Two caveats, so this is not read as more than it is:

• I did not test the exact Flutter version used in the original report — it says "the latest flutter version" without a number, and stable has moved since 2026-08-29.
• Migrating to flutter_lucide may still be worth doing on its own merits, since lucide_icons is unmaintained. That is a separate argument from this build failure.

If whoever hit it can post flutter --version, that would settle whether there is still something to fix.

[dedan-zeraki]

Here's my setup:

[✓] Flutter (Channel stable, 3.47.2, on macOS 26.6.2 25G83 darwin-arm64, locale
en-GB) [412ms]
• Flutter version 3.47.2 on channel stable at /Users/dedan/flutter
• Upstream repository https://github.com/flutter/flutter.git
• Framework revision d3b14c8769 (11 days ago), 2026-08-26 16:07:51 -0700
• Engine revision a804b26164
• Dart version 3.13.2
• DevTools version 2.60.0
• Feature flags: enable-web, enable-linux-desktop, enable-macos-desktop,
enable-windows-desktop, enable-android, enable-ios, cli-animations,
enable-native-assets, enable-record-use, enable-swift-package-manager,
omit-legacy-version-file, enable-lldb-debugging, enable-uiscene-migration

[Pivii]

Thanks for the version — that settles it, and it contradicts my analysis above.

At your framework revision d3b14c8769 (3.47.2), IconData is final:

packages/flutter/lib/src/widgets/icon_data.dart:23
final class IconData {

I checked 3.35.7 and 3.41.2, where it is still @immutable class, and wrongly concluded the change had been reverted before reaching stable. It landed between 3.41.2 and 3.47.2.

So this is reproducible and should stay open — please disregard my suggestion to close it. Since lucide_icons is unmaintained, migrating to flutter_lucide looks like the fix rather than an optional cleanup.