3 files changed, 8 insertions, 3 deletions
diff --git a/src/libexpr/flake/flake.cc b/src/libexpr/flake/flake.cc
index a8f05efb6..21d98089f 100644
--- a/src/libexpr/flake/flake.cc
+++ b/src/libexpr/flake/flake.cc
@@ -584,6 +584,8 @@ static void prim_callFlake(EvalState & state, const Pos & pos, Value * * args, V
             throw Error("the content hash of flake '%s' doesn't match the hash recorded in the referring lockfile",
                 lazyInput->lockedInput.ref);
 
+        assert(flake.sourceInfo->storePath == lazyInput->lockedInput.computeStorePath(*state.store));
+
         callFlake(state, flake, lazyInput->lockedInput, v);
     } else {
         FlakeCache flakeCache;
@@ -593,6 +595,8 @@ static void prim_callFlake(EvalState & state, const Pos & pos, Value * * args, V
             throw Error("the content hash of repository '%s' doesn't match the hash recorded in the referring lockfile",
                 lazyInput->lockedInput.ref);
 
+        assert(sourceInfo.storePath == lazyInput->lockedInput.computeStorePath(*state.store));
+
         state.mkAttrs(v, 8);
 
         assert(state.store->isValidPath(sourceInfo.storePath));
diff --git a/src/libexpr/flake/lockfile.cc b/src/libexpr/flake/lockfile.cc
index edb7628fd..2696d4710 100644
--- a/src/libexpr/flake/lockfile.cc
+++ b/src/libexpr/flake/lockfile.cc
@@ -25,9 +25,9 @@ nlohmann::json LockedInput::toJson() const
     return json;
 }
 
-Path LockedInput::computeStorePath(Store & store) const
+StorePath LockedInput::computeStorePath(Store & store) const
 {
-    return store.printStorePath(store.makeFixedOutputPath(true, narHash, "source"));
+    return store.makeFixedOutputPath(true, narHash, "source");
 }
 
 LockedInputs::LockedInputs(const nlohmann::json & json)
diff --git a/src/libexpr/flake/lockfile.hh b/src/libexpr/flake/lockfile.hh
index ff1181d13..a9710524b 100644
--- a/src/libexpr/flake/lockfile.hh
+++ b/src/libexpr/flake/lockfile.hh
@@ -6,6 +6,7 @@
 
 namespace nix {
 class Store;
+struct StorePath;
 }
 
 namespace nix::flake {
@@ -53,7 +54,7 @@ struct LockedInput : LockedInputs
 
     nlohmann::json toJson() const;
 
-    Path computeStorePath(Store & store) const;
+    StorePath computeStorePath(Store & store) const;
 };
 
 /* An entire lock file. Note that this cannot be a FlakeInput for the