diff --git a/native/GameCult.Mesh.Quic.Native/README.md b/native/GameCult.Mesh.Quic.Native/README.md
index 92041e8d..825595e5 100644
--- a/native/GameCult.Mesh.Quic.Native/README.md
+++ b/native/GameCult.Mesh.Quic.Native/README.md
@@ -110,11 +110,12 @@ mutation harness that drives the runtime-lifetime scenarios is a Node script and
 a container that cannot run it cannot check the bridge it just built:
 
     docker build -t cultlib-quic-native-dev -f scripts/quic-native-linux-dev.Dockerfile scripts
-    docker run --rm --security-opt seccomp=unconfined -v "${PWD}:/src" -w /src `
-        cultlib-quic-native-dev bash -lc "scripts/build-quic-native.sh && node scripts/mutate-cultmesh.mjs native"
+    docker run --rm --security-opt seccomp=unconfined -v "${PWD}:/src" -w /src cultlib-quic-native-dev bash -lc "scripts/build-quic-native.sh && node scripts/mutate-cultmesh.mjs native"
 
 Both lines are run from the repository root, and the mount is that root wherever
-it is: `${PWD}` in PowerShell, `$(pwd)` in a POSIX shell.
+it is: `${PWD}` in PowerShell, `$(pwd)` in a POSIX shell. The second is one line
+because the shell it is offered to is not decided here; a continuation would have
+to pick one, and a backtick pasted into a POSIX shell is not a continuation.
 
 `--security-opt seccomp=unconfined` is load-bearing, not caution. The
 ThreadSanitizer configuration needs the process's address space where it expects
@@ -125,6 +126,13 @@ with "unexpected memory mapping" — a configuration that never starts, which a
 mutation harness would otherwise read as every mutant being killed. The harness
 stops with that diagnosis rather than reporting kills it did not earn.
 
+The win32-x64 half of the harness needs the checkout somewhere short — near a
+drive root rather than under a deep temporary directory. MSVC builds the bridge
+and its scenario runner through MSBuild, whose file tracker gives out on long
+paths, and the build then fails for every mutant including the no-op control.
+The harness stops on a red control rather than reporting a table of kills, so
+the failure is loud, but it names MSBuild and not the path.
+
 Where an artifact was built is part of what it is. The Linux binary is linked
 against Debian 13's glibc, so a build from anywhere else is a different artifact
 whatever the file name says.
diff --git a/scripts/mutate-cultmesh.mjs b/scripts/mutate-cultmesh.mjs
index ac0711b1..b3d12676 100644
--- a/scripts/mutate-cultmesh.mjs
+++ b/scripts/mutate-cultmesh.mjs
@@ -47,11 +47,15 @@
 // dependencies:
 //
 //   docker build -t cultlib-quic-native-dev -f scripts/quic-native-linux-dev.Dockerfile scripts
-//   docker run --rm --security-opt seccomp=unconfined -v "${PWD}:/src" -w /src `
-//       cultlib-quic-native-dev bash -lc "node scripts/mutate-cultmesh.mjs native"
+//   docker run --rm --security-opt seccomp=unconfined -v "${PWD}:/src" -w /src cultlib-quic-native-dev bash -lc "node scripts/mutate-cultmesh.mjs native"
 //
 // Both from the repository root; the mount is that root wherever it is, as
-// `${PWD}` in PowerShell or `$(pwd)` in a POSIX shell.
+// `${PWD}` in PowerShell or `$(pwd)` in a POSIX shell. The second is one line
+// because a continuation would have to pick one of those shells.
+//
+// The win32-x64 half wants the checkout somewhere short, near a drive root. MSVC
+// builds the bridge through MSBuild, whose file tracker gives out on long paths,
+// and a run from a deep temporary directory fails its own no-op control.
 //
 // The seccomp flag is required, not cautious: the ThreadSanitizer configuration
 // is re-executed under `setarch -R`, and Docker's default profile denies the
diff --git a/scripts/quic-native-linux-dev.Dockerfile b/scripts/quic-native-linux-dev.Dockerfile
index 7c796749..f4b11684 100644
--- a/scripts/quic-native-linux-dev.Dockerfile
+++ b/scripts/quic-native-linux-dev.Dockerfile
@@ -9,8 +9,10 @@
 # runner that mutates it at all.
 #
 #   docker build -t cultlib-quic-native-dev -f scripts/quic-native-linux-dev.Dockerfile scripts
-#   docker run --rm --security-opt seccomp=unconfined -v F:\Projects\CultLib:/src -w /src \
-#       cultlib-quic-native-dev bash -lc "scripts/build-quic-native.sh && node scripts/mutate-cultmesh.mjs native"
+#   docker run --rm --security-opt seccomp=unconfined -v "${PWD}:/src" -w /src cultlib-quic-native-dev bash -lc "scripts/build-quic-native.sh && node scripts/mutate-cultmesh.mjs native"
+#
+# Both from the repository root, and the mount is that root wherever it is:
+# `${PWD}` in PowerShell, `$(pwd)` in a POSIX shell.
 #
 # `--security-opt seccomp=unconfined` is not optional and not caution. The
 # ThreadSanitizer configuration needs the process's address space where it