diff --git a/src/libexpr/flake/lockfile.cc b/src/libexpr/flake/lockfile.cc
index 8d077dc22..8bfb9b2d2 100644
--- a/src/libexpr/flake/lockfile.cc
+++ b/src/libexpr/flake/lockfile.cc
@@ -41,11 +41,6 @@ LockedNode::LockedNode(const nlohmann::json & json)
             fetchers::attrsToJSON(lockedRef.input.toAttrs()));
 }
 
-StorePath LockedNode::computeStorePath(Store & store) const
-{
-    return lockedRef.input.computeStorePath(store);
-}
-
 std::shared_ptr<Node> LockFile::findInput(const InputPath & path)
 {
     auto pos = root;
diff --git a/src/libexpr/flake/lockfile.hh b/src/libexpr/flake/lockfile.hh
index 3543860b1..8f8ff2793 100644
--- a/src/libexpr/flake/lockfile.hh
+++ b/src/libexpr/flake/lockfile.hh
@@ -46,8 +46,6 @@ struct LockedNode : Node
     { }
 
     LockedNode(const nlohmann::json & json);
-
-    StorePath computeStorePath(Store & store) const;
 };
 
 struct LockFile
diff --git a/src/libfetchers/fetchers.cc b/src/libfetchers/fetchers.cc
index 951864314..e505362b2 100644
--- a/src/libfetchers/fetchers.cc
+++ b/src/libfetchers/fetchers.cc
@@ -117,24 +117,6 @@ std::pair<StorePath, Input> Input::fetch(ref<Store> store) const
     if (!scheme)
         throw Error("cannot fetch unsupported input '%s'", attrsToJSON(toAttrs()));
 
-    /* The tree may already be in the Nix store, or it could be
-       substituted (which is often faster than fetching from the
-       original source). So check that. */
-    if (hasAllInfo()) {
-        try {
-            auto storePath = computeStorePath(*store);
-
-            store->ensurePath(storePath);
-
-            debug("using substituted/cached input '%s' in '%s'",
-                to_string(), store->printStorePath(storePath));
-
-            return {std::move(storePath), *this};
-        } catch (Error & e) {
-            debug("substitution of input '%s' failed: %s", to_string(), e.what());
-        }
-    }
-
     auto [storePath, input] = [&]() -> std::pair<StorePath, Input> {
         try {
             return scheme->fetch(store, *this);
@@ -223,14 +205,6 @@ std::string Input::getName() const
     return maybeGetStrAttr(attrs, "name").value_or("source");
 }
 
-StorePath Input::computeStorePath(Store & store) const
-{
-    auto narHash = getNarHash();
-    if (!narHash)
-        throw Error("cannot compute store path for unlocked input '%s'", to_string());
-    return store.makeFixedOutputPath(FileIngestionMethod::Recursive, *narHash, getName());
-}
-
 std::string Input::getType() const
 {
     return getStrAttr(attrs, "type");
diff --git a/src/libfetchers/fetchers.hh b/src/libfetchers/fetchers.hh
index 1affe8f5e..8a5db244a 100644
--- a/src/libfetchers/fetchers.hh
+++ b/src/libfetchers/fetchers.hh
@@ -85,8 +85,6 @@ public:
 
     std::string getName() const;
 
-    StorePath computeStorePath(Store & store) const;
-
     // Convenience functions for common attributes.
     std::string getType() const;
     std::optional<Hash> getNarHash() const;