diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8b28f2d..ddac09b 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,14 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Added
 
+- **`Microsoft.SourceLink.GitHub` package reference restored** (§1.7), at the
+  estate-wide version 10.0.400 and with `PrivateAssets="All"` so it is never a
+  consumer dependency. It had been removed as redundant — the .NET 8+ SDK does emit
+  repository metadata and a source-link document map without it, which is accurate as
+  far as it goes — but the standard requires the explicit reference so that source
+  linking is pinned to a version the estate controls rather than moving with whichever
+  SDK feature band happens to build. The `.nuspec`, README, icon and XML docs are
+  unaffected; the assembly and symbols shift slightly (see below).
 - **Canonical CI shape, CodeQL and Dependabot** per
   [NextIteration.Standards](https://github.com/StuartMeeks/NextIteration.Standards)
   `STANDARD.md` section 3 and 4. `ci.yml` now splits into `build`, a three-platform
@@ -26,6 +34,15 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Changed
 
+- **Central Package Management completed and shared build properties centralised.**
+  `Directory.Packages.props` gains `CentralPackageVersionOverrideEnabled=false`, so a
+  stray inline `Version=` alongside CPM is now a hard build failure instead of being
+  silently ignored (§1.3). The seventeen properties every project restated now live in
+  the root `Directory.Build.props` (§1.2); each csproj keeps only what is genuinely its
+  own. Non-shipping projects (tests, demo) set `GenerateDocumentationFile=false` to opt
+  back out. Verified behaviour-preserving: packed before and after from a clean `obj/`
+  at the same commit, every entry in both the `.nupkg` and `.snupkg` is byte-identical
+  bar the per-pack `.psmdcp` name.
 - **Adopted the standards baseline docs, editor config and SDK pin.**
   `SECURITY.md`, `CONTRIBUTING.md`, `CLAUDE.md` and a pull request template added;
   `.gitignore` and `.editorconfig` replaced with the canonical copies; `global.json`
@@ -38,7 +55,6 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - **`SplashTagline.RandomBuiltIn`'s XML doc corrected** from "~200 quotes" to
   "~300": the built-in pool holds 313 entries. Documentation only; the pool itself
   is unchanged.
-
 - **Test suite migrated to xUnit.net v3 (`xunit.v3` 4.0.0)** from `xunit` 2.9.3.
   Contributor-facing only — no library code, public API, or shipped package
   contents changed. v3 test projects are self-executing console apps and run on
@@ -53,19 +69,13 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
   the suite ran on `net10.0` only. Running the full suite locally now requires
   the .NET 8 runtime alongside the .NET 10 SDK.
 
-### Removed
-
-- **`Microsoft.SourceLink.GitHub` package reference.** The .NET SDK has bundled
-  SourceLink since .NET 8; the explicit reference was redundant. Verified
-  byte-identical `.nuspec` and `.snupkg` output either way — consumers still get
-  repository metadata and step-through sources.
-
 ### Fixed
 
-- **`PackageOutputPath` no longer breaks non-Windows builds.** The hardcoded
-  `C:\nuget-local\` local dev feed is now guarded to Windows; previously every
-  `dotnet build` on Linux/macOS and in CI created a literal `C:\nuget-local\`
-  directory under `src/`.
+- **`PackageOutputPath` no longer points at a machine-local path.** Pack output
+  goes to `artifacts/packages` on every platform (§1.8). It previously pointed at
+  a hardcoded `C:\nuget-local\` dev feed; unguarded that created a literal
+  `C:\nuget-local\` directory under `src/` on Linux, macOS and in CI, and even
+  guarded to Windows it made one contributor's machine layout part of repo config.
 - **CI publish job could not check out the repo.** Its `permissions` block listed
   only `id-token: write`, and GitHub sets every unlisted scope to `none`, leaving
   `actions/checkout` without `contents: read`.
diff --git a/Directory.Build.props b/Directory.Build.props
index 08993bb..8447737 100644
--- a/Directory.Build.props
+++ b/Directory.Build.props
@@ -1,8 +1,41 @@
 <Project>
+
+  <!--
+    STANDARD.md 1.2: every property that is identical across projects lives here
+    rather than being restated per csproj. Fifteen copies is fifteen chances to
+    diverge, and the divergence is silent — nothing fails when one csproj quietly
+    disagrees with its sibling about DebugType.
+
+    A csproj carries only what is genuinely specific to it: PackageId, Version,
+    Description, PackageTags, TargetFrameworks, the package's own URLs, and any
+    real exception. A non-shipping project (tests, a demo) sets
+    GenerateDocumentationFile=false to opt back out — sample and fixture code has
+    no XML docs, and TreatWarningsAsErrors would otherwise fail the build over
+    every missing one.
+
+    EnforceCodeStyleInBuild is deliberately absent. STANDARD.md 1.2.1 is blocked:
+    TreatWarningsAsErrors promotes every advisory .editorconfig preference to a
+    hard failure, which produced 490 build errors in Auth. It needs a per-rule
+    gate-versus-advisory decision before it can be added here.
+  -->
   <PropertyGroup>
     <Nullable>enable</Nullable>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <SatelliteResourceLanguages>en</SatelliteResourceLanguages>
+    <AnalysisLevel>latest</AnalysisLevel>
+    <GenerateDocumentationFile>true</GenerateDocumentationFile>
+    <EnablePackageValidation>true</EnablePackageValidation>
+    <IncludeSymbols>true</IncludeSymbols>
+    <SymbolPackageFormat>snupkg</SymbolPackageFormat>
+    <DebugType>portable</DebugType>
+    <PublishRepositoryUrl>true</PublishRepositoryUrl>
+    <EmbedUntrackedSources>true</EmbedUntrackedSources>
+    <ContinuousIntegrationBuild Condition="'$(GITHUB_ACTIONS)' == 'true'">true</ContinuousIntegrationBuild>
+    <PackageLicenseExpression>MIT</PackageLicenseExpression>
+    <Copyright>© Stuart Meeks</Copyright>
     <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
     <Authors>Stuart Meeks</Authors>
     <Company>Next Iteration</Company>
   </PropertyGroup>
+
 </Project>
diff --git a/Directory.Packages.props b/Directory.Packages.props
index 266a47c..36b9c02 100644
--- a/Directory.Packages.props
+++ b/Directory.Packages.props
@@ -1,12 +1,26 @@
 <Project>
   <PropertyGroup>
     <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>
+    <!--
+      Hard-fail if a csproj declares <PackageReference Version="…" /> alongside
+      CPM. Without this MSBuild silently ignores the inline version and uses the
+      central one — which is the exact drift this file exists to prevent, and it
+      prevents it without ever saying so. See STANDARD.md 1.3.
+    -->
+    <CentralPackageVersionOverrideEnabled>false</CentralPackageVersionOverrideEnabled>
   </PropertyGroup>
 
   <ItemGroup>
+    <!-- Not runtime-aligned: a single common floor at the version actually built
+         and tested against. All three are pre-1.0 and version independently of the
+         .NET runtime, so a per-TFM floor would be meaningless — breaking changes
+         land between minors. STANDARD.md 1.5, not 1.4. -->
     <PackageVersion Include="Figgle" Version="0.6.6" />
     <PackageVersion Include="Figgle.Fonts" Version="0.6.6" />
     <PackageVersion Include="Spectre.Console" Version="0.57.2" />
+    <!-- Build-time only (PrivateAssets=All), never a consumer dependency.
+         STANDARD.md 1.7, at the estate-wide version. -->
+    <PackageVersion Include="Microsoft.SourceLink.GitHub" Version="10.0.400" />
   </ItemGroup>
 
   <ItemGroup Label="Test">
diff --git a/demo/NextIteration.SpectreConsole.Splash.Demo/NextIteration.SpectreConsole.Splash.Demo.csproj b/demo/NextIteration.SpectreConsole.Splash.Demo/NextIteration.SpectreConsole.Splash.Demo.csproj
index 2151a8a..0bc124c 100644
--- a/demo/NextIteration.SpectreConsole.Splash.Demo/NextIteration.SpectreConsole.Splash.Demo.csproj
+++ b/demo/NextIteration.SpectreConsole.Splash.Demo/NextIteration.SpectreConsole.Splash.Demo.csproj
@@ -3,9 +3,11 @@
 	<PropertyGroup>
 		<OutputType>Exe</OutputType>
 		<TargetFramework>net10.0</TargetFramework>
-		<ImplicitUsings>enable</ImplicitUsings>
-		<Nullable>enable</Nullable>
 		<IsPackable>false</IsPackable>
+		<!-- Opts out of the Directory.Build.props default. Sample code carries no
+		     XML docs, and TreatWarningsAsErrors would fail the build over every
+		     missing one. Same reasoning as the test project (STANDARD.md 2.7). -->
+		<GenerateDocumentationFile>false</GenerateDocumentationFile>
 	</PropertyGroup>
 
 	<ItemGroup>
diff --git a/src/NextIteration.SpectreConsole.Splash/NextIteration.SpectreConsole.Splash.csproj b/src/NextIteration.SpectreConsole.Splash/NextIteration.SpectreConsole.Splash.csproj
index 153949d..12625cf 100644
--- a/src/NextIteration.SpectreConsole.Splash/NextIteration.SpectreConsole.Splash.csproj
+++ b/src/NextIteration.SpectreConsole.Splash/NextIteration.SpectreConsole.Splash.csproj
@@ -1,37 +1,26 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
+	<!--
+		Only what is specific to this project. Everything shared with the test and
+		demo projects lives in the root Directory.Build.props (STANDARD.md 1.2).
+	-->
 	<PropertyGroup>
 		<TargetFrameworks>net8.0;net10.0</TargetFrameworks>
-		<ImplicitUsings>enable</ImplicitUsings>
-		<SatelliteResourceLanguages>en</SatelliteResourceLanguages>
-		<GenerateDocumentationFile>true</GenerateDocumentationFile>
-		<AnalysisLevel>latest</AnalysisLevel>
 	</PropertyGroup>
 
 	<PropertyGroup>
 		<PackageId>NextIteration.SpectreConsole.Splash</PackageId>
 		<Version>0.3.0</Version>
 		<Description>Configurable Figgle + Spectre.Console splash screen for .NET CLIs — gradient palette, pluggable tagline strategy, single-markup-call render path.</Description>
-		<GeneratePackageOnBuild>true</GeneratePackageOnBuild>
-		<!-- Local dev feed, Windows only. Unguarded this created a literal
-		     `C:\nuget-local\` directory on Linux/macOS and in CI. -->
-		<PackageOutputPath Condition="$([MSBuild]::IsOSPlatform('Windows'))">C:\nuget-local\</PackageOutputPath>
+		<GeneratePackageOnBuild Condition="'$(Configuration)' == 'Release'">true</GeneratePackageOnBuild>
+		<PackageOutputPath>$(MSBuildThisFileDirectory)..\..\artifacts\packages</PackageOutputPath>
 		<IncludeBuildOutput>true</IncludeBuildOutput>
-		<PackageLicenseExpression>MIT</PackageLicenseExpression>
 		<PackageReadmeFile>README.md</PackageReadmeFile>
 		<PackageProjectUrl>https://github.com/StuartMeeks/NextIteration.SpectreConsole.Splash</PackageProjectUrl>
 		<RepositoryUrl>https://github.com/StuartMeeks/NextIteration.SpectreConsole.Splash.git</RepositoryUrl>
 		<RepositoryType>git</RepositoryType>
 		<PackageTags>spectre;cli;splash;figgle;ascii-art</PackageTags>
 		<PackageIcon>icon.png</PackageIcon>
-		<Copyright>© Stuart Meeks</Copyright>
-		<EnablePackageValidation>true</EnablePackageValidation>
-		<PublishRepositoryUrl>true</PublishRepositoryUrl>
-		<EmbedUntrackedSources>true</EmbedUntrackedSources>
-		<IncludeSymbols>true</IncludeSymbols>
-		<SymbolPackageFormat>snupkg</SymbolPackageFormat>
-		<DebugType>portable</DebugType>
-		<ContinuousIntegrationBuild Condition="'$(GITHUB_ACTIONS)' == 'true'">true</ContinuousIntegrationBuild>
 	</PropertyGroup>
 
 	<ItemGroup>
@@ -42,6 +31,7 @@
 		<PackageReference Include="Figgle" />
 		<PackageReference Include="Figgle.Fonts" />
 		<PackageReference Include="Spectre.Console" />
+		<PackageReference Include="Microsoft.SourceLink.GitHub" PrivateAssets="All" />
 		<None Include="..\..\README.md" Pack="true" PackagePath="\" />
 		<None Include="icon.png" Pack="true" PackagePath="" />
 	</ItemGroup>
diff --git a/tests/NextIteration.SpectreConsole.Splash.Tests/NextIteration.SpectreConsole.Splash.Tests.csproj b/tests/NextIteration.SpectreConsole.Splash.Tests/NextIteration.SpectreConsole.Splash.Tests.csproj
index 0a1b375..8f03bba 100644
--- a/tests/NextIteration.SpectreConsole.Splash.Tests/NextIteration.SpectreConsole.Splash.Tests.csproj
+++ b/tests/NextIteration.SpectreConsole.Splash.Tests/NextIteration.SpectreConsole.Splash.Tests.csproj
@@ -6,7 +6,6 @@
 		<TargetFrameworks>net8.0;net10.0</TargetFrameworks>
 		<!-- xUnit.net v3 test projects are self-executing console apps. -->
 		<OutputType>Exe</OutputType>
-		<ImplicitUsings>enable</ImplicitUsings>
 		<IsPackable>false</IsPackable>
 		<IsTestProject>true</IsTestProject>
 		<!-- Opts out of the Directory.Build.props default. Test and fixture code