diff --git a/src/libexpr/flake/flake.cc b/src/libexpr/flake/flake.cc
index 105e76bc6..119c556ac 100644
--- a/src/libexpr/flake/flake.cc
+++ b/src/libexpr/flake/flake.cc
@@ -483,12 +483,12 @@ LockedFlake lockFlake(
                                 } else if (auto follows = std::get_if<1>(&i.second)) {
                                     if (! trustLock) {
                                         // It is possible that the flake has changed,
-                                        // so we must confirm all the follows that are in the lockfile are also in the flake.
+                                        // so we must confirm all the follows that are in the lock file are also in the flake.
                                         auto overridePath(inputPath);
                                         overridePath.push_back(i.first);
                                         auto o = overrides.find(overridePath);
                                         // If the override disappeared, we have to refetch the flake,
-                                        // since some of the inputs may not be present in the lockfile.
+                                        // since some of the inputs may not be present in the lock file.
                                         if (o == overrides.end()) {
                                             mustRefetch = true;
                                             // There's no point populating the rest of the fake inputs,
diff --git a/src/libexpr/flake/lockfile.cc b/src/libexpr/flake/lockfile.cc
index 60b52d578..629d2e669 100644
--- a/src/libexpr/flake/lockfile.cc
+++ b/src/libexpr/flake/lockfile.cc
@@ -36,7 +36,7 @@ LockedNode::LockedNode(const nlohmann::json & json)
     , isFlake(json.find("flake") != json.end() ? (bool) json["flake"] : true)
 {
     if (!lockedRef.input.isLocked())
-        throw Error("lockfile contains mutable lock '%s'",
+        throw Error("lock file contains mutable lock '%s'",
             fetchers::attrsToJSON(lockedRef.input.toAttrs()));
 }
 
diff --git a/src/nix/develop.cc b/src/nix/develop.cc
index ba7ba7c25..4de109754 100644
--- a/src/nix/develop.cc
+++ b/src/nix/develop.cc
@@ -246,6 +246,7 @@ struct Common : InstallableCommand, MixProfile
         "NIX_LOG_FD",
         "NIX_REMOTE",
         "PPID",
+        "SHELL",
         "SHELLOPTS",
         "SSL_CERT_FILE", // FIXME: only want to ignore /no-cert-file.crt
         "TEMP",