diff --git a/src/libstore/build/local-derivation-goal.cc b/src/libstore/build/local-derivation-goal.cc
index b373c74b26a..7dffcc337a5 100644
--- a/src/libstore/build/local-derivation-goal.cc
+++ b/src/libstore/build/local-derivation-goal.cc
@@ -2528,6 +2528,12 @@ SingleDrvOutputs LocalDerivationGoal::registerOutputs()
             [&](const DerivationOutput::CAFixed & dof) {
                 auto & wanted = dof.ca.hash;
 
+                // Replace the output by a fresh copy of itself to make sure
+                // that there's no stale file descriptor pointing to it
+                Path tmpOutput = actualPath + ".tmp";
+                copyFile(actualPath, tmpOutput, true);
+                renameFile(tmpOutput, actualPath);
+
                 auto newInfo0 = newInfoFromCA(DerivationOutput::CAFloating {
                     .method = dof.ca.method,
                     .hashAlgo = wanted.algo,
diff --git a/src/libutil/file-system.cc b/src/libutil/file-system.cc
index 9fa1f62dfc0..218980c2ad7 100644
--- a/src/libutil/file-system.cc
+++ b/src/libutil/file-system.cc
@@ -628,6 +628,11 @@ void copy(const fs::directory_entry & from, const fs::path & to, bool andDelete)
     }
 }
 
+void copyFile(const Path & oldPath, const Path & newPath, bool andDelete)
+{
+    return copy(fs::directory_entry(fs::path(oldPath)), fs::path(newPath), andDelete);
+}
+
 void renameFile(const Path & oldName, const Path & newName)
 {
     fs::rename(oldName, newName);
diff --git a/src/libutil/file-system.hh b/src/libutil/file-system.hh
index 464efc242fe..963265e3412 100644
--- a/src/libutil/file-system.hh
+++ b/src/libutil/file-system.hh
@@ -186,6 +186,13 @@ void renameFile(const Path & src, const Path & dst);
  */
 void moveFile(const Path & src, const Path & dst);
 
+/**
+ * Recursively copy the content of `oldPath` to `newPath`. If `andDelete` is
+ * `true`, then also remove `oldPath` (making this equivalent to `moveFile`, but
+ * with the guaranty that the destination will be “fresh”, with no stale inode
+ * or file descriptor pointing to it).
+ */
+void copyFile(const Path & oldPath, const Path & newPath, bool andDelete);
 
 /**
  * Automatic cleanup of resources.