diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index c8018ad..b75da6b 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -20,7 +20,7 @@ env:
 
 jobs:
   core-tests:
-    name: Core build + tests (ubuntu)
+    name: Core + Execution build + tests (ubuntu)
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v5
@@ -39,13 +39,20 @@ jobs:
       - name: Restore Core projects
         run: |
           dotnet restore src/Snipdeck.Core/Snipdeck.Core.csproj
+          dotnet restore src/Snipdeck.Execution/Snipdeck.Execution.csproj
           dotnet restore tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj
+          dotnet restore tests/Snipdeck.Execution.Tests/Snipdeck.Execution.Tests.csproj
 
       - name: Build Core
-        run: dotnet build src/Snipdeck.Core/Snipdeck.Core.csproj --configuration Release --no-restore
+        run: |
+          dotnet build src/Snipdeck.Core/Snipdeck.Core.csproj --configuration Release --no-restore
+          dotnet build src/Snipdeck.Execution/Snipdeck.Execution.csproj --configuration Release --no-restore
 
       - name: Build + run Core tests
-        run: dotnet test tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-restore --logger "trx;LogFileName=core-tests.trx" --results-directory TestResults
+        run: dotnet test --project tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-restore --report-xunit-trx --report-xunit-trx-filename core-tests.trx --results-directory TestResults
+
+      - name: Build + run Execution tests
+        run: dotnet test --project tests/Snipdeck.Execution.Tests/Snipdeck.Execution.Tests.csproj --configuration Release --no-restore --report-xunit-trx --report-xunit-trx-filename execution-tests.trx --results-directory TestResults
 
       - name: Upload test results
         if: always()
@@ -80,7 +87,7 @@ jobs:
         run: dotnet build tools/Snipdeck.Importer/Snipdeck.Importer.csproj --configuration Release --no-restore
 
       - name: Build + run importer tests
-        run: dotnet test tools/Snipdeck.Importer.Tests/Snipdeck.Importer.Tests.csproj --configuration Release --no-restore --logger "trx;LogFileName=importer-tests.trx" --results-directory TestResults
+        run: dotnet test --project tools/Snipdeck.Importer.Tests/Snipdeck.Importer.Tests.csproj --configuration Release --no-restore --report-xunit-trx --report-xunit-trx-filename importer-tests.trx --results-directory TestResults
 
       - name: Upload test results
         if: always()
@@ -113,7 +120,12 @@ jobs:
         run: dotnet build --configuration Release --no-restore
 
       - name: Run Core tests (sanity check on Windows)
-        run: dotnet test tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-build --logger "trx;LogFileName=core-tests-windows.trx" --results-directory TestResults
+        run: dotnet test --project tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-build --report-xunit-trx --report-xunit-trx-filename core-tests-windows.trx --results-directory TestResults
+
+      # Execution wraps ConPTY and process launching, so Windows is the platform
+      # that actually matters for it — the ubuntu run only proves it is portable.
+      - name: Run Execution tests (ConPTY + process launching are platform-specific)
+        run: dotnet test --project tests/Snipdeck.Execution.Tests/Snipdeck.Execution.Tests.csproj --configuration Release --no-build --report-xunit-trx --report-xunit-trx-filename execution-tests-windows.trx --results-directory TestResults
 
       - name: Upload test results
         if: always()
diff --git a/.github/workflows/release.yml b/.github/workflows/release.yml
index 85f9fe5..3f4ac2d 100644
--- a/.github/workflows/release.yml
+++ b/.github/workflows/release.yml
@@ -87,7 +87,7 @@ jobs:
         run: dotnet restore
 
       - name: Run Core tests
-        run: dotnet test tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-restore
+        run: dotnet test --project tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj --configuration Release --no-restore
 
       - name: Publish Snipdeck.App (win-x64)
         # No -p:Version here — Nerdbank.GitVersioning stamps the assemblies at
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 01ad917..36751ab 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Changed
+- Migrated the test suites to xUnit v3 on Microsoft Testing Platform, replacing
+  the VSTest stack. Development-only; the shipped app is unaffected.
+
+### Fixed
+- CI now runs the `Snipdeck.Execution` test suite, on both Ubuntu and Windows.
+  It was built but never executed, so 61 tests were only ever run locally.
+
 ### Changed
 - Refreshed dependencies to their latest stable releases, including the Windows
   App SDK (2.4.0), WebView2, the Windows SDK build tools, SQLite, the dependency
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index cead4cf..04b12a4 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -21,10 +21,17 @@ dotnet build
 # Build Core only (works on Linux / macOS)
 dotnet build src/Snipdeck.Core
 
-# Run Core tests
-dotnet test tests/Snipdeck.Core.Tests
+# Run the tests (Core, Execution, importer)
+dotnet test --project tests/Snipdeck.Core.Tests
+dotnet test --project tests/Snipdeck.Execution.Tests
+dotnet test --project tools/Snipdeck.Importer.Tests
 ```
 
+The test projects are **xUnit v3**, which runs on Microsoft Testing Platform
+rather than VSTest. The repo-root `global.json` opts `dotnet test` into that
+runner, which is why the project is passed as `--project <path>` rather than as a
+bare argument. TRX reports come from `--report-xunit-trx`, not `--logger trx`.
+
 On a non-Windows machine, restoring the `Snipdeck.App` project requires
 `EnableWindowsTargeting=true`:
 
diff --git a/Directory.Packages.props b/Directory.Packages.props
index d8e6811..a959e19 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -42,12 +42,14 @@
     <PackageVersion Include="Spectre.Console.Cli" Version="0.55.0" />
   </ItemGroup>
 
-  <!-- Tests -->
+  <!-- Tests. xunit v3 ships under the xunit.v3 package ID (the old `xunit` ID is
+       the feature-frozen v2 line) and self-hosts on Microsoft Testing Platform v2,
+       so it replaces the whole VSTest stack: no Microsoft.NET.Test.Sdk, no
+       xunit.runner.visualstudio, and coverage comes from the MTP extension rather
+       than coverlet.collector (a VSTest data collector, inert under MTP). -->
   <ItemGroup>
-    <PackageVersion Include="coverlet.collector" Version="10.0.1" />
-    <PackageVersion Include="Microsoft.NET.Test.Sdk" Version="18.9.0" />
-    <PackageVersion Include="xunit" Version="2.9.3" />
-    <PackageVersion Include="xunit.runner.visualstudio" Version="4.0.0" />
+    <PackageVersion Include="Microsoft.Testing.Extensions.CodeCoverage" Version="18.10.0" />
+    <PackageVersion Include="xunit.v3" Version="4.0.0" />
   </ItemGroup>
 
 </Project>
diff --git a/README.md b/README.md
index d7b13b3..ae1e47d 100644
--- a/README.md
+++ b/README.md
@@ -114,8 +114,9 @@ Requirements:
 # Restore + build everything
 dotnet build
 
-# Run Core unit tests
-dotnet test tests/Snipdeck.Core.Tests
+# Run the unit tests
+dotnet test --project tests/Snipdeck.Core.Tests
+dotnet test --project tests/Snipdeck.Execution.Tests
 ```
 
 The `Snipdeck.Core` project targets `net10.0` and is fully portable, so
@@ -137,10 +138,10 @@ Snipdeck is built on the work of these open-source projects, with thanks to
 their authors and maintainers:
 
 - [.NET Community Toolkit](https://github.com/CommunityToolkit/dotnet) — MVVM source generators and helpers (MIT)
-- [Coverlet](https://github.com/coverlet-coverage/coverlet) — code-coverage collection (MIT)
 - [H.NotifyIcon](https://github.com/HavenDV/H.NotifyIcon) — system-tray icon and menu (MIT)
 - [Jdenticon](https://github.com/dmester/jdenticon-net) — identicons for CLIs without a custom icon (MIT)
 - [Markdig](https://github.com/xoofx/markdig) — Markdown rendering for Snip descriptions (BSD-2-Clause)
+- [Microsoft Testing Platform](https://github.com/microsoft/testfx) — runs the test suites and collects code coverage (MIT)
 - [Microsoft.Extensions.DependencyInjection](https://github.com/dotnet/runtime) — dependency injection (MIT)
 - [Nerdbank.GitVersioning](https://github.com/dotnet/Nerdbank.GitVersioning) — git-derived versioning (MIT)
 - [Porta.Pty](https://github.com/tomlm/Porta.Pty) — cross-platform pseudo-terminal (ConPTY) for running commands (MIT)
diff --git a/global.json b/global.json
new file mode 100644
index 0000000..3140116
--- /dev/null
+++ b/global.json
@@ -0,0 +1,5 @@
+{
+  "test": {
+    "runner": "Microsoft.Testing.Platform"
+  }
+}
diff --git a/src/Snipdeck.Core/ViewModels/SettingsViewModel.cs b/src/Snipdeck.Core/ViewModels/SettingsViewModel.cs
index c90a011..100ecd4 100644
--- a/src/Snipdeck.Core/ViewModels/SettingsViewModel.cs
+++ b/src/Snipdeck.Core/ViewModels/SettingsViewModel.cs
@@ -117,7 +117,7 @@ public SettingsViewModel(
             new("Spectre.Console", "Console UI for the SnipCommand import tool.", new Uri("https://github.com/spectreconsole/spectre.console"), "MIT"),
             new("Nerdbank.GitVersioning", "Derives the version from git history.", new Uri("https://github.com/dotnet/Nerdbank.GitVersioning"), "MIT"),
             new("xUnit", "Unit-testing framework.", new Uri("https://github.com/xunit/xunit"), "Apache-2.0"),
-            new("Coverlet", "Code-coverage collection for tests.", new Uri("https://github.com/coverlet-coverage/coverlet"), "MIT"),
+            new("Microsoft Testing Platform", "Runs the test suites and collects code coverage.", new Uri("https://github.com/microsoft/testfx"), "MIT"),
         ];
 
         [ObservableProperty]
diff --git a/tests/Snipdeck.Core.Tests/Engine/SubstitutionEngineTests.cs b/tests/Snipdeck.Core.Tests/Engine/SubstitutionEngineTests.cs
index cb48a52..9d1c918 100644
--- a/tests/Snipdeck.Core.Tests/Engine/SubstitutionEngineTests.cs
+++ b/tests/Snipdeck.Core.Tests/Engine/SubstitutionEngineTests.cs
@@ -81,8 +81,8 @@ public void Repeated_missing_token_is_listed_once_only()
                 new Dictionary<string, string?>());
 
             Assert.Equal("{missing} and {missing} again", result.Text);
-            Assert.Single(result.UnresolvedTokens);
-            Assert.Equal("missing", result.UnresolvedTokens[0]);
+            var token = Assert.Single(result.UnresolvedTokens);
+            Assert.Equal("missing", token);
         }
 
         [Fact]
diff --git a/tests/Snipdeck.Core.Tests/Services/BackupServiceTests.cs b/tests/Snipdeck.Core.Tests/Services/BackupServiceTests.cs
index 0f6d1e7..5fc8160 100644
--- a/tests/Snipdeck.Core.Tests/Services/BackupServiceTests.cs
+++ b/tests/Snipdeck.Core.Tests/Services/BackupServiceTests.cs
@@ -54,7 +54,7 @@ public async Task CreateBackupAsync_returns_null_when_source_missing()
             var clock = new FakeClock(new DateTimeOffset(2026, 5, 29, 12, 0, 0, TimeSpan.Zero));
             var service = BuildService(clock);
 
-            var info = await service.CreateBackupAsync();
+            var info = await service.CreateBackupAsync(TestContext.Current.CancellationToken);
 
             Assert.Null(info);
             Assert.False(Directory.Exists(_backupDirectory) && Directory.EnumerateFiles(_backupDirectory).Any());
@@ -67,12 +67,12 @@ public async Task CreateBackupAsync_copies_source_to_timestamped_destination()
             var clock = new FakeClock(new DateTimeOffset(2026, 5, 29, 12, 34, 56, 789, TimeSpan.Zero));
             var service = BuildService(clock);
 
-            var info = await service.CreateBackupAsync();
+            var info = await service.CreateBackupAsync(TestContext.Current.CancellationToken);
 
             Assert.NotNull(info);
             Assert.True(File.Exists(info!.FilePath));
             Assert.EndsWith("snipstore_20260529_123456789.json", info.FilePath);
-            Assert.Equal("hello", await File.ReadAllTextAsync(info.FilePath));
+            Assert.Equal("hello", await File.ReadAllTextAsync(info.FilePath, TestContext.Current.CancellationToken));
             Assert.Equal(5, info.SizeBytes);
             Assert.Equal(clock.UtcNow, info.CreatedAtUtc);
         }
@@ -84,7 +84,7 @@ public async Task CreateBackupAsync_creates_missing_backup_directory()
             Assert.False(Directory.Exists(_backupDirectory));
 
             var clock = new FakeClock(new DateTimeOffset(2026, 5, 29, 12, 0, 0, TimeSpan.Zero));
-            await BuildService(clock).CreateBackupAsync();
+            await BuildService(clock).CreateBackupAsync(TestContext.Current.CancellationToken);
 
             Assert.True(Directory.Exists(_backupDirectory));
         }
@@ -97,9 +97,9 @@ public async Task CreateBackupAsync_appends_collision_suffix_when_clock_repeats(
             var clock = new FakeClock(fixedTime);
             var service = BuildService(clock);
 
-            var first = await service.CreateBackupAsync();
-            var second = await service.CreateBackupAsync();
-            var third = await service.CreateBackupAsync();
+            var first = await service.CreateBackupAsync(TestContext.Current.CancellationToken);
+            var second = await service.CreateBackupAsync(TestContext.Current.CancellationToken);
+            var third = await service.CreateBackupAsync(TestContext.Current.CancellationToken);
 
             Assert.NotEqual(first!.FilePath, second!.FilePath);
             Assert.NotEqual(second.FilePath, third!.FilePath);
@@ -117,7 +117,7 @@ public async Task CreateBackupAsync_prunes_backups_beyond_retention()
 
             for (var i = 0; i < 5; i++)
             {
-                await service.CreateBackupAsync();
+                await service.CreateBackupAsync(TestContext.Current.CancellationToken);
                 clock.Advance(TimeSpan.FromSeconds(1));
             }
 
@@ -143,14 +143,14 @@ public async Task CreateBackupAsync_reads_retention_lazily_from_provider()
             // Fill up under the initial retention of 5.
             for (var i = 0; i < 5; i++)
             {
-                await service.CreateBackupAsync();
+                await service.CreateBackupAsync(TestContext.Current.CancellationToken);
                 clock.Advance(TimeSpan.FromSeconds(1));
             }
             Assert.Equal(5, Directory.GetFiles(_backupDirectory, "snipstore_*.json").Length);
 
             // Tighten retention and back up again: the next prune honours the new value.
             retention = 2;
-            await service.CreateBackupAsync();
+            await service.CreateBackupAsync(TestContext.Current.CancellationToken);
 
             Assert.Equal(2, Directory.GetFiles(_backupDirectory, "snipstore_*.json").Length);
         }
@@ -164,7 +164,7 @@ public async Task CreateBackupAsync_clamps_non_positive_provider_value_to_one()
 
             for (var i = 0; i < 4; i++)
             {
-                await service.CreateBackupAsync();
+                await service.CreateBackupAsync(TestContext.Current.CancellationToken);
                 clock.Advance(TimeSpan.FromSeconds(1));
             }
 
@@ -186,19 +186,19 @@ public async Task PruneStep_does_not_touch_unrelated_files_in_backup_directory()
             WriteSource();
             Directory.CreateDirectory(_backupDirectory);
             var sibling = Path.Combine(_backupDirectory, "not-a-backup.txt");
-            await File.WriteAllTextAsync(sibling, "untouched");
+            await File.WriteAllTextAsync(sibling, "untouched", TestContext.Current.CancellationToken);
 
             var clock = new FakeClock(new DateTimeOffset(2026, 5, 29, 12, 0, 0, TimeSpan.Zero));
             var service = BuildService(clock, retention: 1);
 
             for (var i = 0; i < 5; i++)
             {
-                await service.CreateBackupAsync();
+                await service.CreateBackupAsync(TestContext.Current.CancellationToken);
                 clock.Advance(TimeSpan.FromSeconds(1));
             }
 
             Assert.True(File.Exists(sibling));
-            Assert.Equal("untouched", await File.ReadAllTextAsync(sibling));
+            Assert.Equal("untouched", await File.ReadAllTextAsync(sibling, TestContext.Current.CancellationToken));
         }
 
         [Fact]
@@ -208,13 +208,13 @@ public async Task ListBackupsAsync_returns_newest_first_with_parsed_timestamps()
             var clock = new FakeClock(new DateTimeOffset(2026, 5, 29, 12, 0, 0, TimeSpan.Zero));
             var service = BuildService(clock);
 
-            await service.CreateBackupAsync();
+            await service.CreateBackupAsync(TestContext.Current.CancellationToken);
             clock.Advance(TimeSpan.FromSeconds(5));
-            await service.CreateBackupAsync();
+            await service.CreateBackupAsync(TestContext.Current.CancellationToken);
             clock.Advance(TimeSpan.FromSeconds(5));
-            await service.CreateBackupAsync();
+            await service.CreateBackupAsync(TestContext.Current.CancellationToken);
 
-            var list = await service.ListBackupsAsync();
+            var list = await service.ListBackupsAsync(TestContext.Current.CancellationToken);
 
             Assert.Equal(3, list.Count);
             Assert.True(list[0].CreatedAtUtc > list[1].CreatedAtUtc);
@@ -227,7 +227,7 @@ public async Task ListBackupsAsync_returns_empty_when_directory_missing()
             var clock = new FakeClock(DateTimeOffset.UtcNow);
             var service = BuildService(clock);
 
-            var list = await service.ListBackupsAsync();
+            var list = await service.ListBackupsAsync(TestContext.Current.CancellationToken);
 
             Assert.Empty(list);
         }
diff --git a/tests/Snipdeck.Core.Tests/Services/ExamplesSeedTests.cs b/tests/Snipdeck.Core.Tests/Services/ExamplesSeedTests.cs
index 3a7fa58..eb72849 100644
--- a/tests/Snipdeck.Core.Tests/Services/ExamplesSeedTests.cs
+++ b/tests/Snipdeck.Core.Tests/Services/ExamplesSeedTests.cs
@@ -95,8 +95,8 @@ public async Task Seed_round_trips_through_the_json_store()
                 var store = new JsonSnipStore(Path.Combine(tempDir, "store.json"));
                 var original = ExamplesSeed.Build();
 
-                await store.SaveAsync(original);
-                var loaded = await store.LoadAsync();
+                await store.SaveAsync(original, TestContext.Current.CancellationToken);
+                var loaded = await store.LoadAsync(TestContext.Current.CancellationToken);
 
                 Assert.Equal(original.Clis.Count, loaded.Clis.Count);
                 Assert.Equal(original.Snips.Count, loaded.Snips.Count);
diff --git a/tests/Snipdeck.Core.Tests/Services/IconAssetStorageTests.cs b/tests/Snipdeck.Core.Tests/Services/IconAssetStorageTests.cs
index c26ee68..45247e1 100644
--- a/tests/Snipdeck.Core.Tests/Services/IconAssetStorageTests.cs
+++ b/tests/Snipdeck.Core.Tests/Services/IconAssetStorageTests.cs
@@ -51,7 +51,7 @@ public async Task DeleteIconAsync_ignores_parent_directory_traversal()
         {
             // A file outside the icons directory that a malformed IconRef tries to reach.
             var victim = Path.Combine(_baseDirectory, "important.txt");
-            await File.WriteAllTextAsync(victim, "keep me");
+            await File.WriteAllTextAsync(victim, "keep me", TestContext.Current.CancellationToken);
 
             await _storage.DeleteIconAsync("../important.txt");
 
@@ -62,7 +62,7 @@ public async Task DeleteIconAsync_ignores_parent_directory_traversal()
         public async Task DeleteIconAsync_ignores_absolute_paths()
         {
             var victim = Path.Combine(_baseDirectory, "outside.txt");
-            await File.WriteAllTextAsync(victim, "keep me");
+            await File.WriteAllTextAsync(victim, "keep me", TestContext.Current.CancellationToken);
 
             // Path.Combine(base, absolute) discards base — an unguarded delete would hit this.
             await _storage.DeleteIconAsync(victim);
diff --git a/tests/Snipdeck.Core.Tests/Services/JsonSettingsStoreTests.cs b/tests/Snipdeck.Core.Tests/Services/JsonSettingsStoreTests.cs
index 3486b78..68bdbf1 100644
--- a/tests/Snipdeck.Core.Tests/Services/JsonSettingsStoreTests.cs
+++ b/tests/Snipdeck.Core.Tests/Services/JsonSettingsStoreTests.cs
@@ -30,7 +30,7 @@ public async Task LoadAsync_returns_defaults_when_file_missing()
         {
             var store = new JsonSettingsStore(PathIn("settings.json"));
 
-            var config = await store.LoadAsync();
+            var config = await store.LoadAsync(TestContext.Current.CancellationToken);
 
             Assert.Equal(AppConfig.CurrentSchemaVersion, config.SchemaVersion);
             Assert.Null(config.StoragePath);
@@ -58,9 +58,9 @@ await store.SaveAsync(new AppConfig
                     Modifiers = HotkeyModifiers.Control | HotkeyModifiers.Shift,
                     Key = "Space",
                 },
-            });
+            }, TestContext.Current.CancellationToken);
 
-            var loaded = await store.LoadAsync();
+            var loaded = await store.LoadAsync(TestContext.Current.CancellationToken);
 
             Assert.Equal("/data/store", loaded.StoragePath);
             Assert.Equal("/data/backups", loaded.BackupDirectory);
@@ -76,7 +76,7 @@ public async Task SaveAsync_creates_missing_parent_directory()
             var nested = PathIn("a/b/settings.json");
             var store = new JsonSettingsStore(nested);
 
-            await store.SaveAsync(new AppConfig());
+            await store.SaveAsync(new AppConfig(), TestContext.Current.CancellationToken);
 
             Assert.True(File.Exists(nested));
         }
@@ -87,7 +87,7 @@ public async Task SaveAsync_does_not_leave_tmp_file_behind_on_success()
             var path = PathIn("settings.json");
             var store = new JsonSettingsStore(path);
 
-            await store.SaveAsync(new AppConfig());
+            await store.SaveAsync(new AppConfig(), TestContext.Current.CancellationToken);
 
             Assert.False(File.Exists(path + ".tmp"));
             Assert.True(File.Exists(path));
@@ -100,21 +100,21 @@ public async Task LoadAsync_throws_when_schema_version_is_newer_than_supported()
             var futureJson = $$"""
                 { "schemaVersion": {{AppConfig.CurrentSchemaVersion + 1}} }
                 """;
-            await File.WriteAllTextAsync(path, futureJson);
+            await File.WriteAllTextAsync(path, futureJson, TestContext.Current.CancellationToken);
 
             var store = new JsonSettingsStore(path);
 
-            await Assert.ThrowsAsync<InvalidOperationException>(() => store.LoadAsync());
+            await Assert.ThrowsAsync<InvalidOperationException>(() => store.LoadAsync(TestContext.Current.CancellationToken));
         }
 
         [Fact]
         public async Task LoadAsync_repairs_a_missing_hotkey_with_the_default()
         {
             var path = PathIn("settings.json");
-            await File.WriteAllTextAsync(path, "{}");
+            await File.WriteAllTextAsync(path, "{}", TestContext.Current.CancellationToken);
 
             var store = new JsonSettingsStore(path);
-            var loaded = await store.LoadAsync();
+            var loaded = await store.LoadAsync(TestContext.Current.CancellationToken);
 
             Assert.NotNull(loaded.Hotkey);
             Assert.Equal(HotkeyModifiers.Control | HotkeyModifiers.Alt, loaded.Hotkey.Modifiers);
@@ -126,7 +126,7 @@ public async Task SaveAsync_throws_on_null_config()
         {
             var store = new JsonSettingsStore(PathIn("settings.json"));
 
-            await Assert.ThrowsAsync<ArgumentNullException>(() => store.SaveAsync(null!));
+            await Assert.ThrowsAsync<ArgumentNullException>(() => store.SaveAsync(null!, TestContext.Current.CancellationToken));
         }
     }
 }
diff --git a/tests/Snipdeck.Core.Tests/Services/JsonSnipStoreTests.cs b/tests/Snipdeck.Core.Tests/Services/JsonSnipStoreTests.cs
index 39aa2fa..b964596 100644
--- a/tests/Snipdeck.Core.Tests/Services/JsonSnipStoreTests.cs
+++ b/tests/Snipdeck.Core.Tests/Services/JsonSnipStoreTests.cs
@@ -38,7 +38,7 @@ public async Task LoadAsync_returns_empty_document_when_file_missing()
         {
             var store = new JsonSnipStore(PathIn("store.json"));
 
-            var document = await store.LoadAsync();
+            var document = await store.LoadAsync(TestContext.Current.CancellationToken);
 
             Assert.Equal(SnipStoreDocument.CurrentSchemaVersion, document.SchemaVersion);
             Assert.Empty(document.Clis);
@@ -88,8 +88,8 @@ public async Task SaveAsync_then_LoadAsync_round_trips_full_document()
                 },
             };
 
-            await store.SaveAsync(original);
-            var loaded = await store.LoadAsync();
+            await store.SaveAsync(original, TestContext.Current.CancellationToken);
+            var loaded = await store.LoadAsync(TestContext.Current.CancellationToken);
 
             Assert.Equal(SnipStoreDocument.CurrentSchemaVersion, loaded.SchemaVersion);
 
@@ -123,7 +123,7 @@ public async Task SaveAsync_creates_missing_parent_directory()
             var nested = PathIn("a/b/c/store.json");
             var store = new JsonSnipStore(nested);
 
-            await store.SaveAsync(new SnipStoreDocument());
+            await store.SaveAsync(new SnipStoreDocument(), TestContext.Current.CancellationToken);
 
             Assert.True(File.Exists(nested));
         }
@@ -134,7 +134,7 @@ public async Task SaveAsync_does_not_leave_tmp_file_behind_on_success()
             var path = PathIn("store.json");
             var store = new JsonSnipStore(path);
 
-            await store.SaveAsync(new SnipStoreDocument());
+            await store.SaveAsync(new SnipStoreDocument(), TestContext.Current.CancellationToken);
 
             Assert.False(File.Exists(path + ".tmp"));
             Assert.True(File.Exists(path));
@@ -149,14 +149,14 @@ public async Task SaveAsync_overwrites_existing_file()
             await store.SaveAsync(new SnipStoreDocument
             {
                 Clis = { new Cli { Name = "first" } },
-            });
+            }, TestContext.Current.CancellationToken);
 
             await store.SaveAsync(new SnipStoreDocument
             {
                 Clis = { new Cli { Name = "second" } },
-            });
+            }, TestContext.Current.CancellationToken);
 
-            var loaded = await store.LoadAsync();
+            var loaded = await store.LoadAsync(TestContext.Current.CancellationToken);
             var cli = Assert.Single(loaded.Clis);
             Assert.Equal("second", cli.Name);
         }
@@ -172,11 +172,11 @@ public async Task LoadAsync_throws_when_schema_version_is_newer_than_supported()
                   "snips": []
                 }
                 """;
-            await File.WriteAllTextAsync(path, futureJson);
+            await File.WriteAllTextAsync(path, futureJson, TestContext.Current.CancellationToken);
 
             var store = new JsonSnipStore(path);
 
-            await Assert.ThrowsAsync<InvalidOperationException>(() => store.LoadAsync());
+            await Assert.ThrowsAsync<InvalidOperationException>(() => store.LoadAsync(TestContext.Current.CancellationToken));
         }
 
         [Fact]
@@ -184,7 +184,7 @@ public async Task SaveAsync_throws_on_null_document()
         {
             var store = new JsonSnipStore(PathIn("store.json"));
 
-            await Assert.ThrowsAsync<ArgumentNullException>(() => store.SaveAsync(null!));
+            await Assert.ThrowsAsync<ArgumentNullException>(() => store.SaveAsync(null!, TestContext.Current.CancellationToken));
         }
 
         [Fact]
@@ -200,7 +200,7 @@ public async Task Concurrent_saves_leave_a_consistent_well_formed_file()
 
             await Task.WhenAll(tasks);
 
-            var loaded = await store.LoadAsync();
+            var loaded = await store.LoadAsync(TestContext.Current.CancellationToken);
             var cli = Assert.Single(loaded.Clis);
             Assert.StartsWith("cli-", cli.Name);
             Assert.False(File.Exists(path + ".tmp"));
@@ -224,9 +224,9 @@ await store.SaveAsync(new SnipStoreDocument
                         },
                     },
                 },
-            });
+            }, TestContext.Current.CancellationToken);
 
-            var json = await File.ReadAllTextAsync(path);
+            var json = await File.ReadAllTextAsync(path, TestContext.Current.CancellationToken);
             Assert.Contains("\"type\": \"choice\"", json);
         }
     }
diff --git a/tests/Snipdeck.Core.Tests/Services/SnipFilterTests.cs b/tests/Snipdeck.Core.Tests/Services/SnipFilterTests.cs
index bb0eb04..695718a 100644
--- a/tests/Snipdeck.Core.Tests/Services/SnipFilterTests.cs
+++ b/tests/Snipdeck.Core.Tests/Services/SnipFilterTests.cs
@@ -72,8 +72,8 @@ public void Search_matches_command_template()
 
             var result = SnipFilter.Apply(snips, "users", null).ToList();
 
-            Assert.Single(result);
-            Assert.Equal("b", result[0].Title);
+            var match = Assert.Single(result);
+            Assert.Equal("b", match.Title);
         }
 
         [Fact]
@@ -87,8 +87,8 @@ public void Search_matches_tag()
 
             var result = SnipFilter.Apply(snips, "deploy", null).ToList();
 
-            Assert.Single(result);
-            Assert.Equal("a", result[0].Title);
+            var match = Assert.Single(result);
+            Assert.Equal("a", match.Title);
         }
 
         [Fact]
@@ -120,8 +120,8 @@ public void Search_and_tag_apply_together_as_an_AND_filter()
 
             var result = SnipFilter.Apply(snips, "logs", "read").ToList();
 
-            Assert.Single(result);
-            Assert.Equal("Read logs", result[0].Title);
+            var match = Assert.Single(result);
+            Assert.Equal("Read logs", match.Title);
         }
 
         [Fact]
diff --git a/tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj b/tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj
index 9276705..7cbb623 100644
--- a/tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj
+++ b/tests/Snipdeck.Core.Tests/Snipdeck.Core.Tests.csproj
@@ -2,6 +2,7 @@
 
   <PropertyGroup>
     <TargetFramework>net10.0</TargetFramework>
+    <OutputType>Exe</OutputType>
     <IsPackable>false</IsPackable>
     <!--
       Test-only suppressions:
@@ -14,10 +15,8 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="coverlet.collector" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" />
-    <PackageReference Include="xunit" />
-    <PackageReference Include="xunit.runner.visualstudio" />
+    <PackageReference Include="Microsoft.Testing.Extensions.CodeCoverage" />
+    <PackageReference Include="xunit.v3" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/tests/Snipdeck.Core.Tests/ViewModels/SettingsViewModelTests.cs b/tests/Snipdeck.Core.Tests/ViewModels/SettingsViewModelTests.cs
index 43c9eaa..c8547d0 100644
--- a/tests/Snipdeck.Core.Tests/ViewModels/SettingsViewModelTests.cs
+++ b/tests/Snipdeck.Core.Tests/ViewModels/SettingsViewModelTests.cs
@@ -217,9 +217,9 @@ public async Task ChangeStoragePath_moves_the_store_to_an_empty_target_then_rest
             var target = Directory.CreateTempSubdirectory("snipdeck-tgt-").FullName;
             try
             {
-                await File.WriteAllTextAsync(Path.Combine(current, "store.json"), "{}");
+                await File.WriteAllTextAsync(Path.Combine(current, "store.json"), "{}", TestContext.Current.CancellationToken);
                 _ = Directory.CreateDirectory(Path.Combine(current, "icons"));
-                await File.WriteAllTextAsync(Path.Combine(current, "icons", "a.png"), "x");
+                await File.WriteAllTextAsync(Path.Combine(current, "icons", "a.png"), "x", TestContext.Current.CancellationToken);
                 Directory.Delete(target); // target must not exist yet for a clean "move"
 
                 var vm = BuildForStorage(current, out var picker, out var ix, out var restart, out var store);
@@ -250,8 +250,8 @@ public async Task ChangeStoragePath_adopts_an_existing_store_without_moving_the_
             var target = Directory.CreateTempSubdirectory("snipdeck-tgt-").FullName;
             try
             {
-                await File.WriteAllTextAsync(Path.Combine(current, "store.json"), "{}");
-                await File.WriteAllTextAsync(Path.Combine(target, "store.json"), "{}"); // target already has a store
+                await File.WriteAllTextAsync(Path.Combine(current, "store.json"), "{}", TestContext.Current.CancellationToken);
+                await File.WriteAllTextAsync(Path.Combine(target, "store.json"), "{}", TestContext.Current.CancellationToken); // target already has a store
 
                 var vm = BuildForStorage(current, out var picker, out var ix, out var restart, out var store);
                 picker.NextFolder = target;
@@ -278,7 +278,7 @@ public async Task ChangeStoragePath_does_nothing_when_the_user_cancels()
             var target = Directory.CreateTempSubdirectory("snipdeck-tgt-").FullName;
             try
             {
-                await File.WriteAllTextAsync(Path.Combine(current, "store.json"), "{}");
+                await File.WriteAllTextAsync(Path.Combine(current, "store.json"), "{}", TestContext.Current.CancellationToken);
 
                 var vm = BuildForStorage(current, out var picker, out var ix, out var restart, out var store);
                 picker.NextFolder = target;
@@ -304,7 +304,7 @@ public async Task ChangeStoragePath_notifies_when_the_restart_cannot_be_initiate
             var target = Directory.CreateTempSubdirectory("snipdeck-tgt-").FullName;
             try
             {
-                await File.WriteAllTextAsync(Path.Combine(target, "store.json"), "{}"); // adopt path, no file ops
+                await File.WriteAllTextAsync(Path.Combine(target, "store.json"), "{}", TestContext.Current.CancellationToken); // adopt path, no file ops
 
                 var vm = BuildForStorage(current, out var picker, out var ix, out var restart, out var store);
                 picker.NextFolder = target;
@@ -333,7 +333,7 @@ public async Task ChangeStoragePath_rejects_a_folder_nested_in_the_current_store
             var current = Directory.CreateTempSubdirectory("snipdeck-cur-").FullName;
             try
             {
-                await File.WriteAllTextAsync(Path.Combine(current, "store.json"), "{}");
+                await File.WriteAllTextAsync(Path.Combine(current, "store.json"), "{}", TestContext.Current.CancellationToken);
                 var nested = Path.Combine(current, "icons");
                 _ = Directory.CreateDirectory(nested);
 
diff --git a/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelCommandsTests.cs b/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelCommandsTests.cs
index fb0031f..3743ece 100644
--- a/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelCommandsTests.cs
+++ b/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelCommandsTests.cs
@@ -274,8 +274,8 @@ public async Task NewSnip_only_acts_when_a_CLI_is_selected()
             vm.SelectedCliChoice = vm.CliChoices.Single(c => c.Cli?.Id == cli.Id);
             await vm.NewSnipCommand.ExecuteAsync(null);
 
-            Assert.Single(store.Document.Snips);
-            Assert.Equal("New", store.Document.Snips[0].Title);
+            var created = Assert.Single(store.Document.Snips);
+            Assert.Equal("New", created.Title);
         }
 
         [Fact]
@@ -348,7 +348,7 @@ public async Task DeleteCurrentCli_deletes_the_icon_asset()
             var store = new InMemorySnipStore(doc);
             var ix = new FakeShellInteractions { NextConfirmResult = true };
             var vm = new ShellViewModel(store, new FakeClipboardService(), new FakeClock(DateTimeOffset.UtcNow), ix, icons, new FakeExternalLinkService());
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
             vm.SelectedCliChoice = vm.CliChoices.Single(c => c.Cli?.Id == cli.Id);
 
             await vm.DeleteCurrentCliCommand.ExecuteAsync(null);
@@ -560,8 +560,8 @@ public async Task OpenTrash_shows_only_trashed_snips()
             vm.OpenTrash();
 
             var trash = Assert.IsType<TrashViewModel>(vm.CurrentContent);
-            Assert.Single(trash.Snips);
-            Assert.Equal("Binned", trash.Snips[0].Title);
+            var binned = Assert.Single(trash.Snips);
+            Assert.Equal("Binned", binned.Title);
         }
 
         [Fact]
@@ -659,14 +659,14 @@ public async Task NewCli_adds_the_cli_and_writes_icon_bytes_when_provided()
             var clip = new FakeClipboardService();
             var clock = new FakeClock(DateTimeOffset.UtcNow);
             var vmWithIcons = new ShellViewModel(store, clip, clock, ix, icons, new FakeExternalLinkService());
-            await vmWithIcons.LoadAsync();
+            await vmWithIcons.LoadAsync(TestContext.Current.CancellationToken);
 
             await vmWithIcons.NewCliCommand.ExecuteAsync(null);
 
-            Assert.Single(store.Document.Clis);
-            Assert.Equal("inv-app", store.Document.Clis[0].Name);
+            var created = Assert.Single(store.Document.Clis);
+            Assert.Equal("inv-app", created.Name);
             Assert.True(icons.Saved.ContainsKey(newCli.Id));
-            Assert.StartsWith("icons/", store.Document.Clis[0].IconRef);
+            Assert.StartsWith("icons/", created.IconRef);
         }
     }
 }
diff --git a/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelNavTests.cs b/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelNavTests.cs
index f8bc48e..76aad2f 100644
--- a/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelNavTests.cs
+++ b/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelNavTests.cs
@@ -124,7 +124,7 @@ public async Task Selecting_a_search_result_shows_only_that_snip_even_when_title
                 new FakeShellInteractions(),
                 new FakeIconAssetStorage(),
                 new FakeExternalLinkService());
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             var result = vm.GetSearchSuggestions("deploy").Single(r => r.SnipId == second.Id);
             vm.SelectSearchResult(result);
diff --git a/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelTests.cs b/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelTests.cs
index e3ed8fb..6fe14f8 100644
--- a/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelTests.cs
+++ b/tests/Snipdeck.Core.Tests/ViewModels/ShellViewModelTests.cs
@@ -83,7 +83,7 @@ public async Task After_LoadAsync_home_choice_is_selected_and_content_is_a_HomeV
             var doc = SampleDocument(out _, out _);
             var vm = NewShellViewModel(new InMemorySnipStore(doc));
 
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             Assert.NotNull(vm.SelectedCliChoice);
             Assert.True(vm.SelectedCliChoice!.IsAll);
@@ -96,7 +96,7 @@ public async Task CliChoices_contains_home_followed_by_cli_choices_in_alphabetic
             var doc = SampleDocument(out _, out _);
             var vm = NewShellViewModel(new InMemorySnipStore(doc));
 
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             Assert.Equal(3, vm.CliChoices.Count);
             Assert.True(vm.CliChoices[0].IsAll);
@@ -109,7 +109,7 @@ public async Task Selecting_a_cli_swaps_content_to_a_CliViewModel_and_rebuilds_t
         {
             var doc = SampleDocument(out var plAppId, out _);
             var vm = NewShellViewModel(new InMemorySnipStore(doc));
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             vm.SelectedCliChoice = vm.CliChoices.Single(c => c.Cli?.Id == plAppId);
 
@@ -128,7 +128,7 @@ public async Task ShowHome_shows_the_launcher_and_clears_the_tag_selection()
         {
             var doc = SampleDocument(out var plAppId, out _);
             var vm = NewShellViewModel(new InMemorySnipStore(doc));
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             vm.SelectedCliChoice = vm.CliChoices.Single(c => c.Cli?.Id == plAppId);
             vm.ShowHome();
@@ -145,7 +145,7 @@ public async Task Changing_search_text_rebuilds_content()
         {
             var doc = SampleDocument(out _, out _);
             var vm = NewShellViewModel(new InMemorySnipStore(doc));
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             var first = vm.CurrentContent;
             vm.SearchText = "deploy";
@@ -159,7 +159,7 @@ public async Task OpenSettings_swaps_content_for_a_SettingsViewModel()
         {
             var doc = SampleDocument(out _, out _);
             var vm = NewShellViewModel(new InMemorySnipStore(doc));
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             vm.OpenSettings(NewSettingsViewModel());
 
@@ -171,7 +171,7 @@ public async Task Changing_cli_after_OpenSettings_returns_to_shell_content()
         {
             var doc = SampleDocument(out var plAppId, out _);
             var vm = NewShellViewModel(new InMemorySnipStore(doc));
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             vm.OpenSettings(NewSettingsViewModel());
             vm.SelectedCliChoice = vm.CliChoices.Single(c => c.Cli?.Id == plAppId);
diff --git a/tests/Snipdeck.Core.Tests/ViewModels/SnipEditorViewModelTests.cs b/tests/Snipdeck.Core.Tests/ViewModels/SnipEditorViewModelTests.cs
index a5b42ed..793ad02 100644
--- a/tests/Snipdeck.Core.Tests/ViewModels/SnipEditorViewModelTests.cs
+++ b/tests/Snipdeck.Core.Tests/ViewModels/SnipEditorViewModelTests.cs
@@ -69,8 +69,8 @@ public void RemoveParameter_removes_the_given_row()
 
             vm.RemoveParameter(vm.Parameters[0]);
 
-            Assert.Single(vm.Parameters);
-            Assert.Equal("b", vm.Parameters[0].Name);
+            var remaining = Assert.Single(vm.Parameters);
+            Assert.Equal("b", remaining.Name);
         }
 
         [Fact]
@@ -104,8 +104,8 @@ public void BuildUpdatedSnip_preserves_identity_and_applies_edits()
             Assert.Equal(2, built.Tags.Count);
             Assert.True(built.IsFavourite);
             Assert.Equal(3, built.UsageCount);
-            Assert.Single(built.Parameters);
-            Assert.Equal("x", built.Parameters[0].Name);
+            var parameter = Assert.Single(built.Parameters);
+            Assert.Equal("x", parameter.Name);
         }
 
         [Fact]
diff --git a/tests/Snipdeck.Execution.Tests/Services/SqliteCommandHistoryStoreTests.cs b/tests/Snipdeck.Execution.Tests/Services/SqliteCommandHistoryStoreTests.cs
index c291cfc..34d3bde 100644
--- a/tests/Snipdeck.Execution.Tests/Services/SqliteCommandHistoryStoreTests.cs
+++ b/tests/Snipdeck.Execution.Tests/Services/SqliteCommandHistoryStoreTests.cs
@@ -49,9 +49,9 @@ public async Task Added_run_round_trips_through_query_and_get()
             var snip = Guid.NewGuid();
             var entry = Entry(snip, rawGz: [1, 2, 3, 4], truncated: true);
 
-            await _store.AddAsync(entry, retentionPerSnip: 50);
+            await _store.AddAsync(entry, retentionPerSnip: 50, cancellationToken: TestContext.Current.CancellationToken);
 
-            var all = await _store.QueryAsync();
+            var all = await _store.QueryAsync(cancellationToken: TestContext.Current.CancellationToken);
             var stored = Assert.Single(all);
             Assert.Equal(entry.Id, stored.Id);
             Assert.Equal(entry.CliId, stored.CliId);
@@ -66,7 +66,7 @@ public async Task Added_run_round_trips_through_query_and_get()
             Assert.True(stored.OutputTruncated);
             Assert.Equal([1, 2, 3, 4], stored.RawStreamGz);
 
-            var fetched = await _store.GetAsync(entry.Id);
+            var fetched = await _store.GetAsync(entry.Id, TestContext.Current.CancellationToken);
             Assert.NotNull(fetched);
             Assert.Equal(entry.Id, fetched!.Id);
         }
@@ -74,18 +74,18 @@ public async Task Added_run_round_trips_through_query_and_get()
         [Fact]
         public async Task Get_returns_null_for_unknown_id()
         {
-            Assert.Null(await _store.GetAsync(Guid.NewGuid()));
+            Assert.Null(await _store.GetAsync(Guid.NewGuid(), TestContext.Current.CancellationToken));
         }
 
         [Fact]
         public async Task Query_returns_newest_first()
         {
             var snip = Guid.NewGuid();
-            await _store.AddAsync(Entry(snip, command: "old", minutesAfterBase: 0), 50);
-            await _store.AddAsync(Entry(snip, command: "middle", minutesAfterBase: 5), 50);
-            await _store.AddAsync(Entry(snip, command: "newest", minutesAfterBase: 10), 50);
+            await _store.AddAsync(Entry(snip, command: "old", minutesAfterBase: 0), 50, TestContext.Current.CancellationToken);
+            await _store.AddAsync(Entry(snip, command: "middle", minutesAfterBase: 5), 50, TestContext.Current.CancellationToken);
+            await _store.AddAsync(Entry(snip, command: "newest", minutesAfterBase: 10), 50, TestContext.Current.CancellationToken);
 
-            var all = await _store.QueryAsync();
+            var all = await _store.QueryAsync(cancellationToken: TestContext.Current.CancellationToken);
             Assert.Equal(["newest", "middle", "old"], all.Select(e => e.ResolvedCommand));
         }
 
@@ -94,10 +94,10 @@ public async Task Query_filters_by_snip()
         {
             var snipA = Guid.NewGuid();
             var snipB = Guid.NewGuid();
-            await _store.AddAsync(Entry(snipA, command: "a-cmd"), 50);
-            await _store.AddAsync(Entry(snipB, command: "b-cmd"), 50);
+            await _store.AddAsync(Entry(snipA, command: "a-cmd"), 50, TestContext.Current.CancellationToken);
+            await _store.AddAsync(Entry(snipB, command: "b-cmd"), 50, TestContext.Current.CancellationToken);
 
-            var onlyA = await _store.QueryAsync(snipId: snipA);
+            var onlyA = await _store.QueryAsync(snipId: snipA, cancellationToken: TestContext.Current.CancellationToken);
             var stored = Assert.Single(onlyA);
             Assert.Equal("a-cmd", stored.ResolvedCommand);
         }
@@ -106,13 +106,13 @@ public async Task Query_filters_by_snip()
         public async Task Query_search_matches_command_or_output_case_insensitively()
         {
             var snip = Guid.NewGuid();
-            await _store.AddAsync(Entry(snip, command: "kubectl describe pod", output: "Running", minutesAfterBase: 0), 50);
-            await _store.AddAsync(Entry(snip, command: "git status", output: "clean tree", minutesAfterBase: 1), 50);
+            await _store.AddAsync(Entry(snip, command: "kubectl describe pod", output: "Running", minutesAfterBase: 0), 50, TestContext.Current.CancellationToken);
+            await _store.AddAsync(Entry(snip, command: "git status", output: "clean tree", minutesAfterBase: 1), 50, TestContext.Current.CancellationToken);
 
-            var byCommand = await _store.QueryAsync(search: "KUBECTL");
+            var byCommand = await _store.QueryAsync(search: "KUBECTL", cancellationToken: TestContext.Current.CancellationToken);
             Assert.Equal("kubectl describe pod", Assert.Single(byCommand).ResolvedCommand);
 
-            var byOutput = await _store.QueryAsync(search: "CLEAN");
+            var byOutput = await _store.QueryAsync(search: "CLEAN", cancellationToken: TestContext.Current.CancellationToken);
             Assert.Equal("git status", Assert.Single(byOutput).ResolvedCommand);
         }
 
@@ -122,10 +122,10 @@ public async Task Add_prunes_oldest_runs_beyond_retention_per_snip()
             var snip = Guid.NewGuid();
             for (var i = 0; i < 5; i++)
             {
-                await _store.AddAsync(Entry(snip, command: $"run-{i}", minutesAfterBase: i), retentionPerSnip: 3);
+                await _store.AddAsync(Entry(snip, command: $"run-{i}", minutesAfterBase: i), retentionPerSnip: 3, cancellationToken: TestContext.Current.CancellationToken);
             }
 
-            var all = await _store.QueryAsync(snipId: snip);
+            var all = await _store.QueryAsync(snipId: snip, cancellationToken: TestContext.Current.CancellationToken);
             Assert.Equal(["run-4", "run-3", "run-2"], all.Select(e => e.ResolvedCommand));
         }
 
@@ -136,12 +136,12 @@ public async Task Retention_is_scoped_per_snip()
             var snipB = Guid.NewGuid();
             for (var i = 0; i < 4; i++)
             {
-                await _store.AddAsync(Entry(snipA, command: $"a-{i}", minutesAfterBase: i), retentionPerSnip: 2);
-                await _store.AddAsync(Entry(snipB, command: $"b-{i}", minutesAfterBase: i), retentionPerSnip: 2);
+                await _store.AddAsync(Entry(snipA, command: $"a-{i}", minutesAfterBase: i), retentionPerSnip: 2, cancellationToken: TestContext.Current.CancellationToken);
+                await _store.AddAsync(Entry(snipB, command: $"b-{i}", minutesAfterBase: i), retentionPerSnip: 2, cancellationToken: TestContext.Current.CancellationToken);
             }
 
-            Assert.Equal(2, (await _store.QueryAsync(snipId: snipA)).Count);
-            Assert.Equal(2, (await _store.QueryAsync(snipId: snipB)).Count);
+            Assert.Equal(2, (await _store.QueryAsync(snipId: snipA, cancellationToken: TestContext.Current.CancellationToken)).Count);
+            Assert.Equal(2, (await _store.QueryAsync(snipId: snipB, cancellationToken: TestContext.Current.CancellationToken)).Count);
         }
 
         [Fact]
@@ -150,10 +150,10 @@ public async Task Retention_of_zero_or_less_skips_pruning()
             var snip = Guid.NewGuid();
             for (var i = 0; i < 4; i++)
             {
-                await _store.AddAsync(Entry(snip, command: $"run-{i}", minutesAfterBase: i), retentionPerSnip: 0);
+                await _store.AddAsync(Entry(snip, command: $"run-{i}", minutesAfterBase: i), retentionPerSnip: 0, cancellationToken: TestContext.Current.CancellationToken);
             }
 
-            Assert.Equal(4, (await _store.QueryAsync(snipId: snip)).Count);
+            Assert.Equal(4, (await _store.QueryAsync(snipId: snip, cancellationToken: TestContext.Current.CancellationToken)).Count);
         }
 
         [Fact]
@@ -162,12 +162,12 @@ public async Task Delete_removes_a_single_run()
             var snip = Guid.NewGuid();
             var keep = Entry(snip, command: "keep", minutesAfterBase: 1);
             var drop = Entry(snip, command: "drop", minutesAfterBase: 0);
-            await _store.AddAsync(keep, 50);
-            await _store.AddAsync(drop, 50);
+            await _store.AddAsync(keep, 50, TestContext.Current.CancellationToken);
+            await _store.AddAsync(drop, 50, TestContext.Current.CancellationToken);
 
-            await _store.DeleteAsync(drop.Id);
+            await _store.DeleteAsync(drop.Id, TestContext.Current.CancellationToken);
 
-            var all = await _store.QueryAsync();
+            var all = await _store.QueryAsync(cancellationToken: TestContext.Current.CancellationToken);
             Assert.Equal("keep", Assert.Single(all).ResolvedCommand);
         }
 
@@ -175,12 +175,12 @@ public async Task Delete_removes_a_single_run()
         public async Task Clear_removes_all_runs()
         {
             var snip = Guid.NewGuid();
-            await _store.AddAsync(Entry(snip), 50);
-            await _store.AddAsync(Entry(snip, minutesAfterBase: 1), 50);
+            await _store.AddAsync(Entry(snip), 50, TestContext.Current.CancellationToken);
+            await _store.AddAsync(Entry(snip, minutesAfterBase: 1), 50, TestContext.Current.CancellationToken);
 
-            await _store.ClearAsync();
+            await _store.ClearAsync(TestContext.Current.CancellationToken);
 
-            Assert.Empty(await _store.QueryAsync());
+            Assert.Empty(await _store.QueryAsync(cancellationToken: TestContext.Current.CancellationToken));
         }
 
         [Fact]
@@ -188,9 +188,9 @@ public async Task Null_raw_stream_round_trips_as_null()
         {
             var snip = Guid.NewGuid();
             var entry = Entry(snip, rawGz: null);
-            await _store.AddAsync(entry, 50);
+            await _store.AddAsync(entry, 50, TestContext.Current.CancellationToken);
 
-            var stored = await _store.GetAsync(entry.Id);
+            var stored = await _store.GetAsync(entry.Id, TestContext.Current.CancellationToken);
             Assert.NotNull(stored);
             Assert.Null(stored!.RawStreamGz);
         }
diff --git a/tests/Snipdeck.Execution.Tests/Snipdeck.Execution.Tests.csproj b/tests/Snipdeck.Execution.Tests/Snipdeck.Execution.Tests.csproj
index 8a1a838..7729126 100644
--- a/tests/Snipdeck.Execution.Tests/Snipdeck.Execution.Tests.csproj
+++ b/tests/Snipdeck.Execution.Tests/Snipdeck.Execution.Tests.csproj
@@ -2,6 +2,7 @@
 
   <PropertyGroup>
     <TargetFramework>net10.0</TargetFramework>
+    <OutputType>Exe</OutputType>
     <IsPackable>false</IsPackable>
     <!--
       Test-only suppressions (mirrors Snipdeck.Core.Tests):
@@ -14,10 +15,8 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="coverlet.collector" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" />
-    <PackageReference Include="xunit" />
-    <PackageReference Include="xunit.runner.visualstudio" />
+    <PackageReference Include="Microsoft.Testing.Extensions.CodeCoverage" />
+    <PackageReference Include="xunit.v3" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/tests/Snipdeck.Execution.Tests/ViewModels/HistoryViewModelTests.cs b/tests/Snipdeck.Execution.Tests/ViewModels/HistoryViewModelTests.cs
index 8706e29..fd787f6 100644
--- a/tests/Snipdeck.Execution.Tests/ViewModels/HistoryViewModelTests.cs
+++ b/tests/Snipdeck.Execution.Tests/ViewModels/HistoryViewModelTests.cs
@@ -35,7 +35,7 @@ public async Task LoadAsync_projects_entries_and_resolves_names()
             store.Entries.Add(Entry());
             var vm = Build(store, new FakeShellInteractions());
 
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             var item = Assert.Single(vm.Items);
             Assert.Equal("My Snip", item.SnipTitle);
@@ -49,7 +49,7 @@ public async Task IsEmpty_is_true_after_loading_with_no_runs()
         {
             var vm = Build(new FakeCommandHistoryStore(), new FakeShellInteractions());
 
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             Assert.True(vm.IsEmpty);
             Assert.Empty(vm.Items);
@@ -61,7 +61,7 @@ public async Task Open_raises_OpenRequested_with_the_run_id()
             var store = new FakeCommandHistoryStore();
             store.Entries.Add(Entry());
             var vm = Build(store, new FakeShellInteractions());
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             Guid? requested = null;
             vm.OpenRequested += (_, id) => requested = id;
@@ -77,7 +77,7 @@ public async Task Delete_removes_the_run_when_confirmed()
             store.Entries.Add(Entry());
             var interactions = new FakeShellInteractions { NextConfirmResult = true };
             var vm = Build(store, interactions);
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             await vm.DeleteCommand.ExecuteAsync(vm.Items[0]);
 
@@ -92,7 +92,7 @@ public async Task Delete_keeps_the_run_when_cancelled()
             store.Entries.Add(Entry());
             var interactions = new FakeShellInteractions { NextConfirmResult = false };
             var vm = Build(store, interactions);
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             await vm.DeleteCommand.ExecuteAsync(vm.Items[0]);
 
@@ -107,7 +107,7 @@ public async Task ClearAll_empties_the_store_when_confirmed()
             store.Entries.Add(Entry("b"));
             var interactions = new FakeShellInteractions { NextConfirmResult = true };
             var vm = Build(store, interactions);
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             await vm.ClearAllCommand.ExecuteAsync(null);
 
@@ -121,7 +121,7 @@ public async Task LoadAsync_passes_search_text_to_the_store()
             var vm = Build(store, new FakeShellInteractions());
             vm.SearchText = "kubectl";
 
-            await vm.LoadAsync();
+            await vm.LoadAsync(TestContext.Current.CancellationToken);
 
             Assert.Equal("kubectl", store.LastSearch);
         }
diff --git a/tools/Snipdeck.Importer.Tests/ParameterSharerTests.cs b/tools/Snipdeck.Importer.Tests/ParameterSharerTests.cs
index 9de14c6..a58fc9f 100644
--- a/tools/Snipdeck.Importer.Tests/ParameterSharerTests.cs
+++ b/tools/Snipdeck.Importer.Tests/ParameterSharerTests.cs
@@ -136,8 +136,8 @@ public void An_existing_same_option_choice_under_a_different_name_is_not_duplica
             AnalyzeAndApply(cli, a, b);
 
             // No second [x,y] choice is added to the CLI; imported snips keep their local "auth".
-            Assert.Single(cli.Parameters);
-            Assert.Equal("authId", cli.Parameters[0].Name);
+            var shared = Assert.Single(cli.Parameters);
+            Assert.Equal("authId", shared.Name);
             Assert.Equal("auth", Assert.Single(a.Parameters).Name);
             Assert.Equal("auth", Assert.Single(b.Parameters).Name);
         }
@@ -188,8 +188,8 @@ public void Two_distinct_same_option_choices_in_one_snip_are_not_collapsed()
             Assert.Equal("cp {source} {dest}", a.CommandTemplate);
             Assert.Equal("cp {source} {dest}", b.CommandTemplate);
             // "source" is promoted; "dest" stays local on each snip.
-            Assert.Single(cli.Parameters);
-            Assert.Equal("source", cli.Parameters[0].Name);
+            var shared = Assert.Single(cli.Parameters);
+            Assert.Equal("source", shared.Name);
             Assert.Equal("dest", Assert.Single(a.Parameters).Name);
             Assert.Equal("dest", Assert.Single(b.Parameters).Name);
         }
diff --git a/tools/Snipdeck.Importer.Tests/Snipdeck.Importer.Tests.csproj b/tools/Snipdeck.Importer.Tests/Snipdeck.Importer.Tests.csproj
index d188c32..369f16d 100644
--- a/tools/Snipdeck.Importer.Tests/Snipdeck.Importer.Tests.csproj
+++ b/tools/Snipdeck.Importer.Tests/Snipdeck.Importer.Tests.csproj
@@ -2,6 +2,7 @@
 
   <PropertyGroup>
     <TargetFramework>net10.0</TargetFramework>
+    <OutputType>Exe</OutputType>
     <IsPackable>false</IsPackable>
     <!--
       Test-only suppressions (mirrors Snipdeck.Core.Tests):
@@ -14,10 +15,8 @@
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="coverlet.collector" />
-    <PackageReference Include="Microsoft.NET.Test.Sdk" />
-    <PackageReference Include="xunit" />
-    <PackageReference Include="xunit.runner.visualstudio" />
+    <PackageReference Include="Microsoft.Testing.Extensions.CodeCoverage" />
+    <PackageReference Include="xunit.v3" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/tools/Snipdeck.Importer.Tests/StoreMergerTests.cs b/tools/Snipdeck.Importer.Tests/StoreMergerTests.cs
index 3baaf12..7da8bc5 100644
--- a/tools/Snipdeck.Importer.Tests/StoreMergerTests.cs
+++ b/tools/Snipdeck.Importer.Tests/StoreMergerTests.cs
@@ -243,8 +243,8 @@ static Snip Named(string token)
             StoreMerger.Apply(doc, plan);
 
             // Only one "Run" snip lands (they were the same command once unified).
-            Assert.Single(doc.Snips);
-            Assert.Equal("x run {authId}", doc.Snips[0].CommandTemplate);
+            var snip = Assert.Single(doc.Snips);
+            Assert.Equal("x run {authId}", snip.CommandTemplate);
         }
 
         [Fact]