Exporting a game

Shipping a good game is one command:

good build windows

It runs four steps in the order that makes them correct, and the order is the whole reason the command exists:

[1/4] compacting assets     source art  ->  one canonical format per kind
[2/4] generating bindings   canonical   ->  lib/good.generated/
[3/4] packing assets        canonical   ->  compressed, encrypted chunks
[4/4] flutter build windows everything on disk  ->  an application

Compaction writes the canonical files. Generation reads those and emits the enums, so it has to follow. Packing reads the generated key material and writes the chunk mapping back into the same file, so it follows generation. flutter build bundles whatever is on disk by then, so it goes last.

Running these by hand in the wrong order does not fail

It produces a build that is subtly stale, not one that errors — which is exactly the mistake this command exists to remove.

What a release build produces

$ good build windows
good build windows
  project:     .
  assets:      release
  encryption:  aes
  compression: normal

[1/4] compacting assets
0 written, 1 up to date, 0 failed.
[2/4] generating bindings
Wrote ./lib/good.generated/textures.dart
1 texture(s), 0 audio file(s).
[3/4] packing assets
  1 asset(s) in 1 chunk(s), grouped by scene (1 scene(s); 0 asset(s) shared or unattributed)
  stripped 1 loose asset(s) now carried in chunks; `good assets compact` rebuilds them
[4/4] flutter build windows

Built windows.

The shipped bundle contains the chunks and not the loose files — each asset ships exactly once:

build/windows/x64/runner/Release/
├── my_game.exe
├── flutter_windows.dll
└── data/flutter_assets/assets/
    └── packed/chunk_shared.dat        ← the assets, compressed and encrypted

The three pages

• The asset pipeline

  Compaction, chunking, compression, encryption, and why the order is compress-then-encrypt.

• Building for a platform

  Every target, the options that matter, and what to do about signing and packaging.

• Troubleshooting

  The failures the pipeline can produce, and what each one means.

Development versus release

The two modes want opposite things, and both are first-class.

	Development	Release
Assets	Loose files	Chunked
Compression	None	gzip
Encryption	None	AES-256-GCM
Asset mapping	Empty	Path → chunk
Resolution	Straight through rootBundle	Through the installed AssetPack
How you get it	flutter run	good build <platform>

Development leaves everything alone. The shortest path from a changed file to seeing it is not to touch it, so flutter run loads loose files and nothing is packed at all.

Nothing in your game code differs between the two. The same logical path resolves through rootBundle in one and out of an encrypted chunk in the other.

good build defaults to release because flutter run is the development path and does not come through here — someone typing good build windows is making something to ship. Pass --assets=development if you want a platform build with loose assets, for a debugging build you intend to poke at.

Before you ship

• flutter analyze is clean.
• lib/good.generated/asset_key.dart is committed — it is the only record of your encryption keys, and losing it orphans every pack already shipped.
• Both assets/ and assets/packed/ are listed under flutter: assets:.
• ensureGameReady() is called before Game.start — it catches a missing asset before the first frame instead of mid-scene.
• A release build has actually been run and launched, not just compiled.

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Next

The asset pipeline →