Devolutions · Marc-André Moreau (mamoreau-devolutions) · Sep 9, 2026 · Sep 9, 2026
diff --git a/README.md b/README.md
@@ -18,6 +18,7 @@ pinned `avalonia-src` producer submodule at commit
 | `interop/` | `Avalonia.Rust` and `Avalonia.Rust.Interop` - the managed-side view-model interop layer |
 | `apps/system-monitor/` | NeoHtop, a real Rust-owned system monitor with compiled AXAML presentation and a packaged NativeAOT host |
 | `apps/pdf-viewer/` | A PDF Oxide-powered sample viewer with rendered page navigation and extracted text |
+| `apps/hash-calculator/` | A streaming checksum utility (MD5, SHA-1, SHA-256, SHA-512, BLAKE3) with compare and copy |
 | `tests/` | Host, IR, and generator test suites |
 | `samples/` | `RustViewModelSample.Managed` - the sample presentation project the host consumes |
 | `build/` | Vendored MSBuild configuration (versioning, signing, analyzers, xunit) |

diff --git a/apps/hash-calculator/.cargo/config.toml b/apps/hash-calculator/.cargo/config.toml
@@ -0,0 +1,5 @@
+[target.x86_64-pc-windows-msvc]
+rustflags = ["-C", "target-feature=+crt-static"]
+
+[target.aarch64-pc-windows-msvc]
+rustflags = ["-C", "target-feature=+crt-static"]
diff --git a/apps/hash-calculator/.gitignore b/apps/hash-calculator/.gitignore
@@ -0,0 +1,6 @@
+.avalonia/
+bin/
+obj/
+target/
+*.user
+*.suo
diff --git a/apps/hash-calculator/Cargo.lock b/apps/hash-calculator/Cargo.lock
diff --git a/apps/hash-calculator/Cargo.toml b/apps/hash-calculator/Cargo.toml
@@ -0,0 +1,17 @@
+[package]
+name = "hash-calculator"
+version = "0.1.0"
+edition = "2021"
+publish = false
+description = "A sample Rustolonia hash calculator for local files"
+
+[dependencies]
+avalonia = { path = "../../rust/avalonia" }
+blake3 = "1"
+digest = "0.10"
+hex = "0.4"
+md-5 = "0.10"
+sha1 = "0.10"
+sha2 = "0.10"
+
+[workspace]
diff --git a/apps/hash-calculator/README.md b/apps/hash-calculator/README.md
@@ -0,0 +1,50 @@
+# Rustolonia hash calculator
+
+This sample is a sibling external consumer under `apps/` that combines
+Rustolonia, Avalonia and streaming checksum crates (`sha2`, `sha1`, `md-5`,
+`blake3`). Rust owns file hashing, algorithm selection, digest comparison and
+the file list; the generated view-model bridge exposes that state to the
+compiled Avalonia presentation. Hashing runs on a dedicated worker thread and
+reads files in 64 KiB chunks so large inputs keep the UI responsive.
+
+With no arguments, the app writes a small sample file to the system temporary
+directory and hashes it with SHA-256. Passing local file paths hashes those
+instead. **Open files** uses Avalonia's platform picker (multi-select). Toggle
+MD5, SHA-1, SHA-256, SHA-512 and BLAKE3 independently. Paste an expected digest
+to mark matching files; **Copy** / **Copy report** write hex to the clipboard.
+
+## Build on Windows x64
+
+From the repository root:
+
+```powershell
+pwsh ./rust/build-app.ps1 `
+  -ProducerRoot ./avalonia-src `
+  -Manifest ./apps/hash-calculator/avalonia-app.json `
+  -UpdateLockFile
+```
+
+The portable bundle is written to `apps/hash-calculator/artifacts/win-x64`.
+Subsequent locked builds omit `-UpdateLockFile`.
+
+## Tests
+
+Run the Rust hashing tests:
+
+```powershell
+Push-Location ./apps/hash-calculator
+cargo test --locked
+Pop-Location
+```
+
+After building, the Windows UI Automation smoke test exercises startup sample
+generation, SHA-256 output, enabling MD5, compare-against-digest and natural
+shutdown:
+
+```powershell
+powershell.exe -NoProfile -STA -ExecutionPolicy Bypass `
+  -File ./apps/hash-calculator/tests/test-bundle.ps1
+```
+
+The app is a portable Win32 GUI bundle, not an installer. File-association
+metadata snippets are under `file-associations/`.
diff --git a/apps/hash-calculator/avalonia-app.json b/apps/hash-calculator/avalonia-app.json
@@ -0,0 +1,15 @@
+{
+  "version": 1,
+  "presentationProject": "managed/Consumer.Presentation.csproj",
+  "viewModelIr": "view-model.ir.json",
+  "generatedAdaptersDirectory": "managed/Generated",
+  "generatedRegistryFile": "generated/RustViewRegistry.g.cs",
+  "generatedRustFile": "generated/generated_view_models.rs",
+  "generatedContractFile": "generated/view-model.contract.md",
+  "cargoManifest": "Cargo.toml",
+  "packageName": "hash-calculator",
+  "binary": "hash-calculator",
+  "rid": "win-x64",
+  "configuration": "Release",
+  "outputDirectory": "artifacts/win-x64"
+}
diff --git a/apps/hash-calculator/file-associations/README.md b/apps/hash-calculator/file-associations/README.md
@@ -0,0 +1,38 @@
+# File type association metadata
+
+These are packaging metadata snippets, not installers. They register a document
+type so the desktop shell launches this application with the selected file path
+as a command-line argument; the runtime side of "open with" is already wired,
+because `App::run` forwards this process's arguments to the managed desktop
+lifetime and `AppScope::activation_items()` returns them normalized (see
+`rust/DESKTOP_FILES.md` in the pinned Avalonia producer checkout).
+
+Deliberately out of scope here: MSIX packaging, `.msi`/`.pkg`/`.deb`/`.rpm`
+installers, notarization, and any store submission. Those belong to whatever
+distribution channel a consumer chooses; this workflow ships a deterministic
+per-RID directory (see `PRODUCTIZATION.md`).
+
+Replace `hash-calculator` (already substituted by `new-app`), the
+extension `.myapp`, and the install path before shipping any of these.
+
+| Platform | File | Applied by |
+| --- | --- | --- |
+| Windows | `windows-file-association.reg` | Your installer writing the same keys, or `reg import` for local testing. |
+| Linux | `linux-desktop-entry.desktop`, `linux-mime-type.xml` | `desktop-file-install` / `xdg-mime install` from your package's post-install step. |
+| macOS | `macos-Info.plist.snippet` | Merged into the `.app` bundle's `Info.plist`. |
+
+## Verifying the runtime side
+
+Once an association is registered, launching a file through the shell reaches
+Rust as an activation item:
+
+```rust
+for item in scope.activation_items()? {
+    // `uri()` is always present; `local_path()` may be `None` on platforms
+    // that hand the application a non-local document reference.
+    println!("open with: {} ({})", item.uri(), item.name());
+}
+```
+
+macOS additionally raises later activations while the application is already
+running; subscribe with `AppScope::on_activation` to receive them.
diff --git a/apps/hash-calculator/file-associations/linux-desktop-entry.desktop b/apps/hash-calculator/file-associations/linux-desktop-entry.desktop
@@ -0,0 +1,16 @@
+[Desktop Entry]
+Type=Application
+Name=hash-calculator
+Comment=Rustolonia hash calculator for local files
+# %F passes the selected file paths as separate arguments. Use %U instead if
+# your application should also receive non-local URIs; both reach Rust through
+# AppScope::activation_items(), which keeps a URI when there is no local path.
+Exec=/opt/hash-calculator/hash-calculator %F
+Icon=hash-calculator
+Terminal=false
+Categories=Utility;
+MimeType=application/x-hash-calculator;
+
+# Install with (from a package post-install step, not from the application):
+#   desktop-file-install --dir="$HOME/.local/share/applications" this-file.desktop
+#   update-desktop-database "$HOME/.local/share/applications"
diff --git a/apps/hash-calculator/file-associations/linux-mime-type.xml b/apps/hash-calculator/file-associations/linux-mime-type.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  shared-mime-info declaration for hash-calculator documents.
+
+  Install with (from a package post-install step):
+    xdg-mime install --mode user this-file.xml
+    update-mime-database "$HOME/.local/share/mime"
+    xdg-mime default hash-calculator.desktop application/x-hash-calculator
+
+  The glob pattern must match the extension used in the .desktop entry.
+-->
+<mime-info xmlns="http://www.freedesktop.org/standards/shared-mime-info">
+  <mime-type type="application/x-hash-calculator">
+    <comment>hash-calculator document</comment>
+    <glob pattern="*.myapp"/>
+    <icon name="hash-calculator"/>
+  </mime-type>
+</mime-info>