diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
new file mode 100644
index 0000000..9c64d0b
--- /dev/null
+++ b/.github/workflows/build.yml
@@ -0,0 +1,47 @@
+name: Build
+
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+permissions:
+  contents: read
+
+jobs:
+  build-and-test:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Check out ReadOnlyDom
+        uses: actions/checkout@v7.0.1
+        with:
+          path: AngleSharp.ReadOnlyDom
+
+      - name: Check out the matching AngleSharp source
+        uses: actions/checkout@v7.0.1
+        with:
+          repository: dv00d00/AngleSharp
+          ref: devel
+          path: AngleSharp
+
+      - name: Set up .NET
+        uses: actions/setup-dotnet@v6.0.0
+        with:
+          dotnet-version: 10.0.x
+
+      - name: Restore
+        run: dotnet restore AngleSharp.ReadOnlyDom.slnx --force --no-cache
+        working-directory: AngleSharp.ReadOnlyDom
+
+      - name: Build
+        run: dotnet build AngleSharp.ReadOnlyDom.slnx -c Release --no-restore -m:1
+        working-directory: AngleSharp.ReadOnlyDom
+
+      - name: Test
+        run: >-
+          dotnet test tests/AngleSharp.ReadOnlyDom.Tests/AngleSharp.ReadOnlyDom.Tests.csproj
+          -c Release -f net10.0 --no-build --no-restore --
+          --minimum-expected-tests 1 --progress off
+        working-directory: AngleSharp.ReadOnlyDom
diff --git a/docs/UPSTREAM_ANGLESHARP_NOTES.md b/docs/UPSTREAM_ANGLESHARP_NOTES.md
index 61b32f8..0c4dc32 100644
--- a/docs/UPSTREAM_ANGLESHARP_NOTES.md
+++ b/docs/UPSTREAM_ANGLESHARP_NOTES.md
@@ -1,4 +1,23 @@
-# AngleSharp generic construction notes
+# AngleSharp upstream dependencies
+
+The object and compact DOM projects exercise generic construction and byte-source APIs that are not in a released
+AngleSharp package yet. Until they ship, `Directory.Build.targets` replaces the AngleSharp package reference with a
+source checkout. The standalone streaming project does not use that override.
+
+## Upstream tracking
+
+Status snapshot: 2026-08-20. All three pull requests are open and mergeable; their Linux and Windows jobs compile the
+changes and then hit the same Fallout/.NET SDK infrastructure failure described in the PR comments.
+
+| Pull request | Relationship to this repository |
+| --- | --- |
+| [AngleSharp/AngleSharp#1285](https://github.com/AngleSharp/AngleSharp/pull/1285) | Handle-oriented HTML tree construction used by the compact arena |
+| [AngleSharp/AngleSharp#1286](https://github.com/AngleSharp/AngleSharp/pull/1286) | Direct `ReadOnlyMemory<byte>` parsing in the retained DOM lanes |
+| [AngleSharp/AngleSharp#1287](https://github.com/AngleSharp/AngleSharp/pull/1287) | Related opt-in custom-DOM whitespace contract; not enabled by default here |
+
+Do not publish the retained DOM packages against the temporary source contract. After #1285 and #1286 land in an
+AngleSharp release, remove the source override, update the central package version, and run the full multi-target suite
+against the package before making either project packable. #1287 can land independently.
 
 ## Handle-oriented tree construction
 
@@ -8,19 +27,13 @@ FsCheck differential testing against AngleSharp 1.5.2 reduced a mismatch to malf
 <table><div><span attr='unterminated>
 ```
 
-The standard mutable DOM foster-parents `div` into `body` before `table`. A DOM built through
-`IDomConstructionElementFactory<TDocument, TElement>` places it outside `html`.
-
-The original `HtmlDomBuilder<TDocument, TElement>.AddElementWithFoster` checked `el is HtmlTemplateElement` and
-`el is HtmlTableElement`. Those AngleSharp core concrete types prevented a custom constructable element from matching
-mutable parser behavior.
-
-The handle-oriented `HtmlTreeBuilder<TDocument, TNode>` now uses parser flags and HTML tag identity instead. Compact parsing
-therefore handles foster parenting, templates, and formatting adoption directly through `ArenaHandle`, without a parallel
-object tree. Differential and smoke coverage retains the malformed-table case above as a regression contract.
+The standard mutable DOM foster-parents `div` into `body` before `table`. The old generic construction path placed it
+outside `html` because foster-parenting checks depended on AngleSharp's concrete element types. The handle-oriented
+tree builder uses parser flags and HTML tag identity instead, so compact parsing can handle foster parenting, templates,
+and formatting adoption directly through `ArenaHandle`, without a parallel object tree. Differential and smoke coverage
+keeps the malformed-table case as a regression contract.
 
-## UTF-8 token-source adapter
+## Standalone UTF-8 lane
 
-The streaming product now owns its native UTF-8 tokenizer, WHATWG entity table, encoding-label table, limits, and sink
-contract, and therefore has no runtime dependency on AngleSharp. The mutable-DOM token-source adapter remains core
-specific; object and compact construction continue to consume the fork until their required construction APIs ship.
+The streaming product owns its tokenizer, WHATWG entity table, encoding-label table, limits, and sink contract. It has
+no runtime dependency on AngleSharp and can be built, tested, and published independently of the upstream work above.
diff --git a/readme.md b/readme.md
index 5a2ee68..d7ca3e4 100644
--- a/readme.md
+++ b/readme.md
@@ -59,7 +59,7 @@ serially because the solution and the fork share AngleSharp output paths:
 ```powershell
 dotnet restore AngleSharp.ReadOnlyDom.slnx --force --no-cache
 dotnet build AngleSharp.ReadOnlyDom.slnx -c Release --no-restore -m:1
-dotnet test tests/AngleSharp.ReadOnlyDom.Tests/AngleSharp.ReadOnlyDom.Tests.csproj -c Release -f net10.0 --no-restore
+dotnet test tests/AngleSharp.ReadOnlyDom.Tests/AngleSharp.ReadOnlyDom.Tests.csproj -c Release -f net10.0 --no-restore -- --minimum-expected-tests 1
 ```
 
 The Release build output should contain an
@@ -345,13 +345,15 @@ dotnet run --project samples/AngleSharp.ReadOnlyDom.MarkdownProxy -c Release
 ```
 
 The Hacker News reader folds a live list page into NDJSON one story at a time and unfurls a link-preview card per row
-on scroll, abandoning each linked page's download at `</head>`. Targets `net11.0` with platform async, so it needs a
-.NET 11 SDK:
+on scroll, abandoning each linked page's download at `</head>`. It builds on the default .NET 10 lane:
 
 ```powershell
 dotnet run --project samples/AngleSharp.ReadOnlyDom.HackerNews -c Release
 ```
 
+With a .NET 11 SDK, pass `-p:Net11Lane=true -p:Net11Async=true` to opt the sample and streaming library into the
+platform-async experiment.
+
 Opinionated text/Markdown projections and safe local Markdown navigation remain runnable examples rather than library
 surface:
 
@@ -360,10 +362,11 @@ dotnet run --project samples/AngleSharp.ReadOnlyDom.ExtractionExamples -c Releas
 dotnet run --project samples/AngleSharp.ReadOnlyDom.MarkdownNavigation -c Release
 ```
 
-Run the test suite from the repository root:
+Run the test suite from the repository root. The minimum count guard prevents a broken test-host configuration from
+reporting success after discovering no tests:
 
 ```powershell
-dotnet test AngleSharp.ReadOnlyDom.slnx -c Release
+dotnet test tests/AngleSharp.ReadOnlyDom.Tests/AngleSharp.ReadOnlyDom.Tests.csproj -c Release -f net10.0 -- --minimum-expected-tests 1
 ```
 
 ## Repository layout
diff --git a/samples/AngleSharp.ReadOnlyDom.HackerNews/AngleSharp.ReadOnlyDom.HackerNews.csproj b/samples/AngleSharp.ReadOnlyDom.HackerNews/AngleSharp.ReadOnlyDom.HackerNews.csproj
index 0ff38df..62eefdc 100644
--- a/samples/AngleSharp.ReadOnlyDom.HackerNews/AngleSharp.ReadOnlyDom.HackerNews.csproj
+++ b/samples/AngleSharp.ReadOnlyDom.HackerNews/AngleSharp.ReadOnlyDom.HackerNews.csproj
@@ -1,10 +1,12 @@
 <Project Sdk="Microsoft.NET.Sdk.Web">
   <PropertyGroup>
-    <TargetFramework>net11.0</TargetFramework>
+    <TargetFramework>net10.0</TargetFramework>
+    <TargetFramework Condition="'$(Net11Lane)' == 'true'">net11.0</TargetFramework>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
-    <LangVersion>preview</LangVersion>
-    <Features>$(Features);runtime-async=on</Features>
+    <UseRuntimeAsync Condition="'$(Net11Async)' == 'true' and '$(TargetFramework)' == 'net11.0'">true</UseRuntimeAsync>
+    <LangVersion Condition="'$(Net11Async)' == 'true' and '$(TargetFramework)' == 'net11.0'">preview</LangVersion>
+    <Features Condition="'$(Net11Async)' == 'true' and '$(TargetFramework)' == 'net11.0'">$(Features);runtime-async=on</Features>
   </PropertyGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\src\AngleSharp.ReadOnlyDom.Streaming\AngleSharp.ReadOnlyDom.Streaming.csproj" />
diff --git a/samples/AngleSharp.ReadOnlyDom.HackerNews/README.md b/samples/AngleSharp.ReadOnlyDom.HackerNews/README.md
index 74bcf96..4f7dc48 100644
--- a/samples/AngleSharp.ReadOnlyDom.HackerNews/README.md
+++ b/samples/AngleSharp.ReadOnlyDom.HackerNews/README.md
@@ -3,12 +3,13 @@
 A Hacker News front end built on two streaming query plans. Nothing is buffered: list HTML is folded into NDJSON one
 story per line, and each row unfurls a link-preview card as it scrolls into view.
 
-Needs a .NET 11 SDK (`net11.0`, platform async on).
+The default lane targets `net10.0`. A .NET 11 SDK can opt into the platform-async experiment without making the
+repository's normal build depend on a preview SDK.
 
 ```powershell
 dotnet run --project samples/AngleSharp.ReadOnlyDom.HackerNews -c Release
 
-# with the library on the same async lane
+# Optional: target net11.0 and put both the app and library on the platform-async lane.
 dotnet run --project samples/AngleSharp.ReadOnlyDom.HackerNews -c Release -p:Net11Lane=true -p:Net11Async=true
 ```
 
@@ -52,12 +53,10 @@ socket goes through a `ConnectCallback` that refuses private, loopback, link-loc
 time, not parse time. Card images are re-served from this origin. Feeds cache 15 s, cards 10 min. Cards load three
 at a time.
 
-**Platform async.** `Features=runtime-async=on` is the switch; `UseRuntimeAsync` alone is a no-op and SDK
-11.0.100-preview.7 has no property for it. Restore does not flow `AdditionalProperties` across a project reference,
-so `Net11Lane`/`Net11Async` must be global `-p:` properties or restore fails NETSDK1005. Emitted state machines: 0
-vs 3 for this app (43,008 B vs 52,224 B), 0 vs 14 for the library (293,376 B vs 309,760 B). Whether it is *faster*
-is unmeasured here — earlier preview-6 runs gained 1–4% on stream shapes while the preview JIT lost 8–12% on the
-synchronous tokenizer loop.
+**Platform async.** The checked-in default is the supported `net10.0` lane. Passing both `Net11Lane=true` and
+`Net11Async=true` targets `net11.0` and adds `Features=runtime-async=on`; the properties must be global `-p:` values so
+restore also applies them to the streaming project reference. The experiment previously emitted 0 compiler-generated
+state machines versus 3 for this app, and 0 versus 14 for the library. Whether it is *faster* remains unmeasured here.
 
 **Limits.** Lexical start/end-tag topology, not corrected tree topology: omitted end tags and foster parenting can
 differ from a DOM converter. A page that declares card metadata below the head, or only from script, gets no card.
diff --git a/src/AngleSharp.ReadOnlyDom.Streaming/AngleSharp.ReadOnlyDom.Streaming.csproj b/src/AngleSharp.ReadOnlyDom.Streaming/AngleSharp.ReadOnlyDom.Streaming.csproj
index c3f8e2d..e6a9375 100644
--- a/src/AngleSharp.ReadOnlyDom.Streaming/AngleSharp.ReadOnlyDom.Streaming.csproj
+++ b/src/AngleSharp.ReadOnlyDom.Streaming/AngleSharp.ReadOnlyDom.Streaming.csproj
@@ -2,16 +2,16 @@
   <PropertyGroup>
     <TargetFrameworks>net8.0;net10.0</TargetFrameworks>
     <TargetFrameworks Condition="'$(Net11Lane)' == 'true'">net8.0;net10.0;net11.0</TargetFrameworks>
-    <UseRuntimeAsync Condition="'$(Net11Async)' == 'true'">true</UseRuntimeAsync>
-    <Features Condition="'$(Net11Async)' == 'true'">$(Features);runtime-async=on</Features>
-    <LangVersion Condition="'$(Net11Async)' == 'true'">preview</LangVersion>
+    <UseRuntimeAsync Condition="'$(Net11Async)' == 'true' and '$(TargetFramework)' == 'net11.0'">true</UseRuntimeAsync>
+    <Features Condition="'$(Net11Async)' == 'true' and '$(TargetFramework)' == 'net11.0'">$(Features);runtime-async=on</Features>
+    <LangVersion Condition="'$(Net11Async)' == 'true' and '$(TargetFramework)' == 'net11.0'">preview</LangVersion>
     <ImplicitUsings>enable</ImplicitUsings>
     <Nullable>enable</Nullable>
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 
   <ItemGroup>
-    <PackageReference Include="System.IO.Pipelines" />
+    <PackageReference Include="System.IO.Pipelines" Condition="'$(TargetFramework)' == 'net8.0'" />
   </ItemGroup>
 
   <ItemGroup>
diff --git a/tests/AngleSharp.ReadOnlyDom.Tests/AngleSharp.ReadOnlyDom.Tests.csproj b/tests/AngleSharp.ReadOnlyDom.Tests/AngleSharp.ReadOnlyDom.Tests.csproj
index 2b80da0..a51fc2e 100644
--- a/tests/AngleSharp.ReadOnlyDom.Tests/AngleSharp.ReadOnlyDom.Tests.csproj
+++ b/tests/AngleSharp.ReadOnlyDom.Tests/AngleSharp.ReadOnlyDom.Tests.csproj
@@ -1,4 +1,4 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
   <PropertyGroup>
     <OutputType>Exe</OutputType>
     <TargetFrameworks>net10.0;net472</TargetFrameworks>
@@ -28,149 +28,7 @@
   </ItemGroup>
 
   <ItemGroup>
-    <None Update="TestData\html5lib-tokenizer\**\*">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\163.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\360.cn.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\aliexpress.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\amazon.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\ask.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\baidu.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\bing.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\blogspot.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\codeproject.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\ebay.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\en.wikipedia.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\flickr.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\florian-rappl.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\godaddy.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\google.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\html5rocks.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\html5test.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\huffingtonpost.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\imdb.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\kickass.to.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\linkedin.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\live.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\mail.ru.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\msn.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\myspace.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\nbc.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\neobux.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\netflix.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\news.google.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\nytimes.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\pcmag.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\peacekeeper.futuremark.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\pinterest.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\qq.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\reddit.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\sitepoint.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\spiegel.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\stackoverflow.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\taobao.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\tmall.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\tumblr.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\vk.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\w3.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\weibo.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\wordpress.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\yahoo.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
-    <None Update="temp\youtube.html">
-      <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
-    </None>
+    <None Update="TestData\html5lib-tokenizer\**\*" CopyToOutputDirectory="PreserveNewest" />
+    <None Update="temp\*.html" CopyToOutputDirectory="PreserveNewest" />
   </ItemGroup>
 </Project>