diff --git a/flake.nix b/flake.nix
index 580f572ff32c6..d1e2934f7b336 100644
--- a/flake.nix
+++ b/flake.nix
@@ -9,8 +9,8 @@
         nixpkgs = self;
       };
 
-      libVersionInfoOverlay = import ./lib/flake-version-info.nix self;
-      lib = (import ./lib).extend libVersionInfoOverlay;
+      libFlakeInfoOverlay = import ./lib/flake-info.nix self;
+      lib = (import ./lib).extend libFlakeInfoOverlay;
 
       forAllSystems = lib.genAttrs lib.systems.flakeExposed;
     in
@@ -72,7 +72,7 @@
       # information rich.
       legacyPackages = forAllSystems (system:
         (import ./. { inherit system; }).extend (final: prev: {
-          lib = prev.lib.extend libVersionInfoOverlay;
+          lib = prev.lib.extend libFlakeInfoOverlay;
         })
       );
 
diff --git a/lib/flake-version-info.nix b/lib/flake-info.nix
similarity index 53%
rename from lib/flake-version-info.nix
rename to lib/flake-info.nix
index de15be94bee8a..dd57462899aa3 100644
--- a/lib/flake-version-info.nix
+++ b/lib/flake-info.nix
@@ -16,5 +16,16 @@ finalLib: prevLib: # lib overlay
     versionSuffix =
       ".${finalLib.substring 0 8 (self.lastModifiedDate or "19700101")}.${self.shortRev or "dirty"}";
     revisionWithDefault = default: self.rev or default;
+
+    # This overrides the nixpkgsStorePathString logic in lib/trivial.nix for
+    # the special case of flakes, where we are in pure eval mode and thus
+    # would not be able to use builtins.storePath to establish a dependency on
+    # this nixpkgs' sources (https://github.com/NixOS/nix/issues/5868).
+    #
+    # However, in this particular case, due to being used from a flake, we *do*
+    # have a string with context for our own sources in the store in the
+    # `outPath` of the `self` flake input, which we obtain by calling toString
+    # on it.
+    nixpkgsStorePathString = toString self;
   };
 }
diff --git a/lib/flake.nix b/lib/flake.nix
index ca09ed5f4a420..eac8e855bf6f7 100644
--- a/lib/flake.nix
+++ b/lib/flake.nix
@@ -5,6 +5,6 @@
     let
       lib0 = import ./.;
     in {
-      lib = lib0.extend (import ./flake-version-info.nix self);
+      lib = lib0.extend (import ./flake-info.nix self);
     };
 }
diff --git a/lib/trivial.nix b/lib/trivial.nix
index b2796096e8bc1..90178deee8471 100644
--- a/lib/trivial.nix
+++ b/lib/trivial.nix
@@ -232,6 +232,48 @@ in {
 
   nixpkgsVersion = builtins.trace "`lib.nixpkgsVersion` is deprecated, use `lib.version` instead!" version;
 
+  /* The store path to this nixpkgs as a string with context. This can be used
+     to incur a dependency on this nixpkgs, for example, to symlink it into a
+     NixOS closure.
+
+     If this nixpkgs is used as a flake directly (via `nixpkgs.lib.trivial`
+     rather than via `import nixpkgs`), or it is already in the Nix store in
+     non-flake usage such as being fetched via `builtins.fetchTarball`,
+     evaluating this attribute is quick and does not copy anything new to the
+     store.
+
+     This is different than pkgs.path if nixpkgs is already in the Nix store,
+     since pkgs.path is a path to nixpkgs rather than a string-with-context,
+     and thus its usage typically, undesirably, results in copying this
+     nixpkgs.
+
+     See: https://github.com/NixOS/nix/issues/5868
+          https://github.com/NixOS/nix/issues/9428
+
+     Type: String
+  */
+
+  nixpkgsStorePathString =
+    # Note: this is overlayed by lib/flake-info.nix if nixpkgs is used directly
+    # as a flake.
+    if lib.strings.isStorePath (toString ../.) then
+      # While `toString ../.` is already a store path here, it doesn't contain
+      # a dependency on that store path in its string context.
+      # We can use `builtins.storePath` to establishes a dependency on an
+      # existing store path that nixpkgs was imported with.
+      if lib.trivial.inPureEvalMode then
+        # However, in pure eval mode, that builtin is not currently supported, see https://github.com/NixOS/nix/issues/5868.
+        # So we fall back to string interpolation of a path, which copies the path that's already in the store to the store once more,
+        # which is slow and gives it a doubly-hashed base name, but there's not much we can do
+        # See also https://github.com/NixOS/nix/issues/9428
+        "${../.}"
+      else
+        # Only outside pure eval we can actually use builtins.storePath, which can re-use the existing store path
+        builtins.storePath ../.
+    else
+      # Here ../. is not in the store already, so we need to use string interpolation to copy the path to the store.
+      "${../.}";
+
   /* Determine whether the function is being called from inside a Nix
      shell.