diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 26ab09b..d16b29a 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -2,9 +2,9 @@ name: Build (Windows)
 
 on:
   push:
-    branches: [ "master", "main", "sow/2026-Q2" ]
+    branches: [ "master", "main", "sow/**" ]
   pull_request:
-    branches: [ "master", "main", "sow/2026-Q2" ]
+    branches: [ "master", "main", "sow/**" ]
   workflow_dispatch:
 
 jobs:
@@ -35,6 +35,36 @@ jobs:
 
       - name: Setup MSBuild
         uses: microsoft/setup-msbuild@v2
+      - name: Compute SAMVersion
+        id: ver
+        shell: pwsh
+        run: |
+          $ErrorActionPreference = 'Stop'
+          # Prefer head_ref when its a sow branch (release-promotion PRs from sow/* to main),
+          # else use base_ref on PR events / ref_name on push events.
+          $headRef = '${{ github.head_ref }}'
+          $baseRef = '${{ github.base_ref }}'
+          $refName = '${{ github.ref_name }}'
+          if ($headRef -match '^sow/\d{4}-Q\d$') {
+            $ref = $headRef
+          } elseif ('${{ github.event_name }}' -eq 'pull_request') {
+            $ref = $baseRef
+          } else {
+            $ref = $refName
+          }
+          # .NET AssemblyVersion components are UInt16 (max 65535). Cap to 60000 for headroom.
+          $run = ${{ github.run_number }} % 60000
+          if ($ref -match 'sow/(\d{4})-Q(\d)') {
+            $v = "$($Matches[1]).$($Matches[2]).$run.0"
+            $src = "branch '$ref'"
+          } else {
+            $now = (Get-Date).ToUniversalTime()
+            $quarter = [int][Math]::Ceiling($now.Month / 3.0)
+            $v = "$($now.Year).$quarter.$run.0"
+            $src = "date $($now.ToString('yyyy-MM-dd')) (ref '$ref' not sow/yyyy-Qx)"
+          }
+          Write-Host "SAMVersion = $v (from $src)"
+          "samversion=$v" | Out-File -FilePath $env:GITHUB_OUTPUT -Append -Encoding utf8
 
       - name: Clone dependency repos (siblings)
         shell: pwsh
@@ -56,8 +86,13 @@ jobs:
           foreach ($r in $deps) {
             if (Test-Path $r) { continue }
             $headRef = '${{ github.head_ref }}'
+            $baseRef = '${{ github.base_ref }}'
+            $refName = '${{ github.ref_name }}'
             $candidates = @()
             if ($headRef) { $candidates += $headRef }
+            # Current sow branch: base_ref on PR events, ref_name on push events.
+            $sowRef = if ($baseRef -match '^sow/') { $baseRef } elseif ($refName -match '^sow/') { $refName } else { '' }
+            if ($sowRef -and $sowRef -ne $headRef) { $candidates += $sowRef }
             $candidates += 'sow/2026-Q2'
             $cloned = $false
             foreach ($cand in $candidates) {
@@ -94,6 +129,7 @@ jobs:
             '/v:m'
             '/p:Configuration=Release'
             '/p:UseSharedCompilation=false'
+            '/p:SAMVersion=${{ steps.ver.outputs.samversion }}'
             '/p:RunPostBuildEvent=OnOutputUpdated'
             "/p:ReferencePath=$windowsRef"
           )
diff --git a/Directory.Build.props b/Directory.Build.props
new file mode 100644
index 0000000..9841655
--- /dev/null
+++ b/Directory.Build.props
@@ -0,0 +1,39 @@
+<Project>
+
+  <PropertyGroup>
+    <!-- Local dev builds default to 1.0.0.0. CI passes /p:SAMVersion=YYYY.Q.<run_number>. -->
+    <SAMVersion Condition="'$(SAMVersion)' == ''">1.0.0.0</SAMVersion>
+    <AssemblyVersion>$(SAMVersion)</AssemblyVersion>
+    <FileVersion>$(SAMVersion)</FileVersion>
+    <Deterministic>true</Deterministic>
+  </PropertyGroup>
+
+  <!--
+    Projects where SDK assembly-attribute generation is disabled (legacy AssemblyInfo.cs
+    with GenerateAssemblyInfo=false) OR projects where the SDK doesn't auto-generate
+    attributes at all (classic-style csprojs that don't set the property — '' evaluates
+    as not 'true') ignore the AssemblyVersion/FileVersion MSBuild properties above.
+    Inject the attributes via a generated source file so those assemblies also get
+    stamped by CI.
+  -->
+  <Target Name="_GenerateSAMVersionFile"
+          BeforeTargets="CoreCompile"
+          Condition="'$(GenerateAssemblyInfo)' != 'true'">
+    <ItemGroup>
+      <_SAMVersionLine Include="// &lt;auto-generated /&gt;" />
+      <_SAMVersionLine Include="[assembly: System.Reflection.AssemblyVersionAttribute(&quot;$(SAMVersion)&quot;)]" />
+      <_SAMVersionLine Include="[assembly: System.Reflection.AssemblyFileVersionAttribute(&quot;$(SAMVersion)&quot;)]" />
+    </ItemGroup>
+    <MakeDir Directories="$(IntermediateOutputPath)" />
+    <WriteLinesToFile
+      File="$(IntermediateOutputPath)SAMVersion.g.cs"
+      Lines="@(_SAMVersionLine)"
+      Overwrite="true"
+      WriteOnlyWhenDifferent="true" />
+    <ItemGroup>
+      <Compile Include="$(IntermediateOutputPath)SAMVersion.g.cs" KeepDuplicates="false" />
+      <FileWrites Include="$(IntermediateOutputPath)SAMVersion.g.cs" />
+    </ItemGroup>
+  </Target>
+
+</Project>
diff --git a/Grasshopper/SAM.Analytical.Grasshopper.TMP/Kernel/AssemblyInfo.cs b/Grasshopper/SAM.Analytical.Grasshopper.TMP/Kernel/AssemblyInfo.cs
index 4d59577..177e4f8 100644
--- a/Grasshopper/SAM.Analytical.Grasshopper.TMP/Kernel/AssemblyInfo.cs
+++ b/Grasshopper/SAM.Analytical.Grasshopper.TMP/Kernel/AssemblyInfo.cs
@@ -1,4 +1,7 @@
-using Grasshopper.Kernel;
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright (c) 2020–2026 Michal Dengusiak & Jakub Ziolkowski and contributors
+
+using Grasshopper.Kernel;
 using System;
 using System.Drawing;
 
diff --git a/Grasshopper/SAM.Analytical.Grasshopper.TMP/Properties/AssemblyInfo.cs b/Grasshopper/SAM.Analytical.Grasshopper.TMP/Properties/AssemblyInfo.cs
index cd4373a..6fc7b87 100644
--- a/Grasshopper/SAM.Analytical.Grasshopper.TMP/Properties/AssemblyInfo.cs
+++ b/Grasshopper/SAM.Analytical.Grasshopper.TMP/Properties/AssemblyInfo.cs
@@ -55,6 +55,3 @@
 //
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
-// [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("1.0.0.0")]
-[assembly: AssemblyFileVersion("1.0.0.0")]
diff --git a/Grasshopper/SAM.Analytical.Grasshopper.TMP/SAM.Analytical.Grasshopper.TMP.csproj b/Grasshopper/SAM.Analytical.Grasshopper.TMP/SAM.Analytical.Grasshopper.TMP.csproj
index 87b8b9f..98cf142 100644
--- a/Grasshopper/SAM.Analytical.Grasshopper.TMP/SAM.Analytical.Grasshopper.TMP.csproj
+++ b/Grasshopper/SAM.Analytical.Grasshopper.TMP/SAM.Analytical.Grasshopper.TMP.csproj
@@ -10,7 +10,6 @@
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
     <UseWindowsForms>true</UseWindowsForms>
     <ImportWindowsDesktopTargets>true</ImportWindowsDesktopTargets>
-	  <Deterministic>false</Deterministic>
 	  <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
 	  <AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath>
   </PropertyGroup>
diff --git a/Grasshopper/SAM.Core.Grasshopper.TMP/Kernel/AssemblyInfo.cs b/Grasshopper/SAM.Core.Grasshopper.TMP/Kernel/AssemblyInfo.cs
index d64e096..5cf95ac 100644
--- a/Grasshopper/SAM.Core.Grasshopper.TMP/Kernel/AssemblyInfo.cs
+++ b/Grasshopper/SAM.Core.Grasshopper.TMP/Kernel/AssemblyInfo.cs
@@ -1,4 +1,7 @@
-using Grasshopper.Kernel;
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright (c) 2020–2026 Michal Dengusiak & Jakub Ziolkowski and contributors
+
+using Grasshopper.Kernel;
 using System;
 using System.Drawing;
 
diff --git a/Grasshopper/SAM.Core.Grasshopper.TMP/Properties/AssemblyInfo.cs b/Grasshopper/SAM.Core.Grasshopper.TMP/Properties/AssemblyInfo.cs
index 0c0032f..874d4fa 100644
--- a/Grasshopper/SAM.Core.Grasshopper.TMP/Properties/AssemblyInfo.cs
+++ b/Grasshopper/SAM.Core.Grasshopper.TMP/Properties/AssemblyInfo.cs
@@ -55,6 +55,3 @@
 //
 // You can specify all the values or you can default the Build and Revision Numbers 
 // by using the '*' as shown below:
-// [assembly: AssemblyVersion("1.0.*")]
-[assembly: AssemblyVersion("1.0.0.0")]
-[assembly: AssemblyFileVersion("1.0.0.0")]
diff --git a/Grasshopper/SAM.Core.Grasshopper.TMP/SAM.Core.Grasshopper.TMP.csproj b/Grasshopper/SAM.Core.Grasshopper.TMP/SAM.Core.Grasshopper.TMP.csproj
index 13098db..715d271 100644
--- a/Grasshopper/SAM.Core.Grasshopper.TMP/SAM.Core.Grasshopper.TMP.csproj
+++ b/Grasshopper/SAM.Core.Grasshopper.TMP/SAM.Core.Grasshopper.TMP.csproj
@@ -11,7 +11,6 @@
 	<UseWindowsForms>true</UseWindowsForms>
 	<ImportWindowsDesktopTargets>true</ImportWindowsDesktopTargets>
 	<StartProgram>C:\Program Files\Rhino 8\System\Rhino.exe</StartProgram>
-	<Deterministic>false</Deterministic>
 	<AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
 	<AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath>
 	<CopyLocalLockFileAssemblies>True</CopyLocalLockFileAssemblies>
diff --git a/SAM_TMP/SAM.Analytical.TMP/Properties/AssemblyInfo.cs b/SAM_TMP/SAM.Analytical.TMP/Properties/AssemblyInfo.cs
index e46b4e2..fc1a18b 100644
--- a/SAM_TMP/SAM.Analytical.TMP/Properties/AssemblyInfo.cs
+++ b/SAM_TMP/SAM.Analytical.TMP/Properties/AssemblyInfo.cs
@@ -1,4 +1,7 @@
-/*
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright (c) 2020–2026 Michal Dengusiak & Jakub Ziolkowski and contributors
+
+/*
  * This file is part of the Sustaiable Analytical Model (SAM)
  * Copyright (c) 2020, the respective contributors. All rights reserved.
  *
diff --git a/SAM_TMP/SAM.Analytical.TMP/SAM.Analytical.TMP.csproj b/SAM_TMP/SAM.Analytical.TMP/SAM.Analytical.TMP.csproj
index 8720753..7de9420 100644
--- a/SAM_TMP/SAM.Analytical.TMP/SAM.Analytical.TMP.csproj
+++ b/SAM_TMP/SAM.Analytical.TMP/SAM.Analytical.TMP.csproj
@@ -2,13 +2,10 @@
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
     <OutputType>Library</OutputType>
-    <Deterministic>false</Deterministic>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
     <AssemblyTitle>SAM.Analytical</AssemblyTitle>
     <Product>SAM.Analytical</Product>
     <Copyright>Copyright (c) 2020-2026 Michal Dengusiak &amp; Jakub Ziolkowski and contributors</Copyright>
-    <AssemblyVersion>1.0.0.0</AssemblyVersion>
-    <FileVersion>1.0.0.0</FileVersion>
 	  <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
 	  <AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath>
   </PropertyGroup>
diff --git a/SAM_TMP/SAM.Core.TMP/Properties/AssemblyInfo.cs b/SAM_TMP/SAM.Core.TMP/Properties/AssemblyInfo.cs
index cf1e05d..2fa9aca 100644
--- a/SAM_TMP/SAM.Core.TMP/Properties/AssemblyInfo.cs
+++ b/SAM_TMP/SAM.Core.TMP/Properties/AssemblyInfo.cs
@@ -1,4 +1,7 @@
-/*
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright (c) 2020–2026 Michal Dengusiak & Jakub Ziolkowski and contributors
+
+/*
  * This file is part of the Sustaiable Analytical Model (SAM)
  * Copyright (c) 2020, the respective contributors. All rights reserved.
  *
diff --git a/SAM_TMP/SAM.Core.TMP/SAM.Core.TMP.csproj b/SAM_TMP/SAM.Core.TMP/SAM.Core.TMP.csproj
index 7f5935b..53fa88d 100644
--- a/SAM_TMP/SAM.Core.TMP/SAM.Core.TMP.csproj
+++ b/SAM_TMP/SAM.Core.TMP/SAM.Core.TMP.csproj
@@ -2,13 +2,10 @@
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
     <OutputType>Library</OutputType>
-    <Deterministic>false</Deterministic>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
     <AssemblyTitle>SAM</AssemblyTitle>
     <Product>SAM</Product>
     <Copyright>Copyright (c) 2020-2026 Michal Dengusiak &amp; Jakub Ziolkowski and contributors</Copyright>
-    <AssemblyVersion>1.0.0.0</AssemblyVersion>
-    <FileVersion>1.0.0.0</FileVersion>
 	  <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
 	  <AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath>
   </PropertyGroup>
diff --git a/SAM_TMP/SAM.Geometry.TMP/Properties/AssemblyInfo.cs b/SAM_TMP/SAM.Geometry.TMP/Properties/AssemblyInfo.cs
index cf1e05d..2fa9aca 100644
--- a/SAM_TMP/SAM.Geometry.TMP/Properties/AssemblyInfo.cs
+++ b/SAM_TMP/SAM.Geometry.TMP/Properties/AssemblyInfo.cs
@@ -1,4 +1,7 @@
-/*
+// SPDX-License-Identifier: LGPL-3.0-or-later
+// Copyright (c) 2020–2026 Michal Dengusiak & Jakub Ziolkowski and contributors
+
+/*
  * This file is part of the Sustaiable Analytical Model (SAM)
  * Copyright (c) 2020, the respective contributors. All rights reserved.
  *
diff --git a/SAM_TMP/SAM.Geometry.TMP/SAM.Geometry.TMP.csproj b/SAM_TMP/SAM.Geometry.TMP/SAM.Geometry.TMP.csproj
index 924393f..de3eb0f 100644
--- a/SAM_TMP/SAM.Geometry.TMP/SAM.Geometry.TMP.csproj
+++ b/SAM_TMP/SAM.Geometry.TMP/SAM.Geometry.TMP.csproj
@@ -2,13 +2,10 @@
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
     <OutputType>Library</OutputType>
-    <Deterministic>false</Deterministic>
     <GenerateAssemblyInfo>false</GenerateAssemblyInfo>
     <AssemblyTitle>SAM</AssemblyTitle>
     <Product>SAM</Product>
     <Copyright>Copyright (c) 2020-2026 Michal Dengusiak &amp; Jakub Ziolkowski and contributors</Copyright>
-    <AssemblyVersion>1.0.0.0</AssemblyVersion>
-    <FileVersion>1.0.0.0</FileVersion>
 	  <AppendTargetFrameworkToOutputPath>false</AppendTargetFrameworkToOutputPath>
 	  <AppendRuntimeIdentifierToOutputPath>false</AppendRuntimeIdentifierToOutputPath>
   </PropertyGroup>