Introduce a type allias for an optional ptr to IExecutionApi

...and replace verbose constructions.

24 files changed, 93 insertions, 103 deletions

diff --git a/src/buildtool/execution_api/common/execution_api.hpp b/src/buildtool/execution_api/common/execution_api.hpp
index 72663c2e..b86ddd1f 100644
--- a/src/buildtool/execution_api/common/execution_api.hpp
+++ b/src/buildtool/execution_api/common/execution_api.hpp
@@ -35,6 +35,7 @@
 class IExecutionApi {
   public:
     using Ptr = std::shared_ptr<IExecutionApi const>;
+    using OptionalPtr = std::optional<gsl::not_null<IExecutionApi const*>>;
 
     IExecutionApi() = default;
     IExecutionApi(IExecutionApi const&) = delete;
@@ -70,7 +71,7 @@ class IExecutionApi {
     [[nodiscard]] virtual auto RetrieveToPaths(
         std::vector<Artifact::ObjectInfo> const& artifacts_info,
         std::vector<std::filesystem::path> const& output_paths,
-        std::optional<gsl::not_null<const IExecutionApi*>> const& alternative =
+        IExecutionApi::OptionalPtr const& alternative =
             std::nullopt) const noexcept -> bool = 0;
 
     /// \brief Retrieve artifacts from CAS and write to file descriptors.
diff --git a/src/buildtool/execution_api/git/git_api.hpp b/src/buildtool/execution_api/git/git_api.hpp
index 53184988..d35000fd 100644
--- a/src/buildtool/execution_api/git/git_api.hpp
+++ b/src/buildtool/execution_api/git/git_api.hpp
@@ -54,8 +54,7 @@ class GitApi final : public IExecutionApi {
     [[nodiscard]] auto RetrieveToPaths(
         std::vector<Artifact::ObjectInfo> const& artifacts_info,
         std::vector<std::filesystem::path> const& output_paths,
-        std::optional<
-            gsl::not_null<const IExecutionApi*>> const& /*alternative*/
+        IExecutionApi::OptionalPtr const& /*alternative*/
         = std::nullopt) const noexcept -> bool override {
         if (artifacts_info.size() != output_paths.size()) {
             Logger::Log(LogLevel::Error,
diff --git a/src/buildtool/execution_api/local/local_api.hpp b/src/buildtool/execution_api/local/local_api.hpp
index 928fb5b8..cbb904ef 100644
--- a/src/buildtool/execution_api/local/local_api.hpp
+++ b/src/buildtool/execution_api/local/local_api.hpp
@@ -78,9 +78,8 @@ class LocalApi final : public IExecutionApi {
     [[nodiscard]] auto RetrieveToPaths(
         std::vector<Artifact::ObjectInfo> const& artifacts_info,
         std::vector<std::filesystem::path> const& output_paths,
-        std::optional<
-            gsl::not_null<const IExecutionApi*>> const& /*alternative*/
-        = std::nullopt) const noexcept -> bool final {
+        IExecutionApi::OptionalPtr const& /*alternative*/ =
+            std::nullopt) const noexcept -> bool final {
         if (artifacts_info.size() != output_paths.size()) {
             Logger::Log(LogLevel::Error,
                         "different number of digests and output paths.");
diff --git a/src/buildtool/execution_api/remote/bazel/bazel_api.cpp b/src/buildtool/execution_api/remote/bazel/bazel_api.cpp
index b475dfe8..f636c265 100644
--- a/src/buildtool/execution_api/remote/bazel/bazel_api.cpp
+++ b/src/buildtool/execution_api/remote/bazel/bazel_api.cpp
@@ -221,8 +221,7 @@ auto BazelApi::CreateAction(
 [[nodiscard]] auto BazelApi::RetrieveToPaths(
     std::vector<Artifact::ObjectInfo> const& artifacts_info,
     std::vector<std::filesystem::path> const& output_paths,
-    std::optional<gsl::not_null<const IExecutionApi*>> const& alternative)
-    const noexcept -> bool {
+    IExecutionApi::OptionalPtr const& alternative) const noexcept -> bool {
     if (artifacts_info.size() != output_paths.size()) {
         Logger::Log(LogLevel::Warning,
                     "different number of digests and output paths.");
diff --git a/src/buildtool/execution_api/remote/bazel/bazel_api.hpp b/src/buildtool/execution_api/remote/bazel/bazel_api.hpp
index a9149450..e5669933 100644
--- a/src/buildtool/execution_api/remote/bazel/bazel_api.hpp
+++ b/src/buildtool/execution_api/remote/bazel/bazel_api.hpp
@@ -62,7 +62,7 @@ class BazelApi final : public IExecutionApi {
     [[nodiscard]] auto RetrieveToPaths(
         std::vector<Artifact::ObjectInfo> const& artifacts_info,
         std::vector<std::filesystem::path> const& output_paths,
-        std::optional<gsl::not_null<const IExecutionApi*>> const& alternative =
+        IExecutionApi::OptionalPtr const& alternative =
             std::nullopt) const noexcept -> bool final;
 
     [[nodiscard]] auto RetrieveToFds(
diff --git a/src/other_tools/ops_maps/archive_fetch_map.cpp b/src/other_tools/ops_maps/archive_fetch_map.cpp
index 883ffa76..db2fc319 100644
--- a/src/other_tools/ops_maps/archive_fetch_map.cpp
+++ b/src/other_tools/ops_maps/archive_fetch_map.cpp
@@ -26,14 +26,13 @@
 
 namespace {
 
-void ProcessContent(
-    std::filesystem::path const& content_path,
-    std::filesystem::path const& target_name,
-    gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
-    std::string const& content,
-    ArchiveFetchMap::SetterPtr const& setter,
-    ArchiveFetchMap::LoggerPtr const& logger) {
+void ProcessContent(std::filesystem::path const& content_path,
+                    std::filesystem::path const& target_name,
+                    gsl::not_null<IExecutionApi const*> const& local_api,
+                    IExecutionApi::OptionalPtr const& remote_api,
+                    std::string const& content,
+                    ArchiveFetchMap::SetterPtr const& setter,
+                    ArchiveFetchMap::LoggerPtr const& logger) {
     // try to back up to remote CAS
     if (remote_api) {
         if (not local_api->RetrieveToCas(
@@ -68,12 +67,11 @@ void ProcessContent(
 
 }  // namespace
 
-auto CreateArchiveFetchMap(
-    gsl::not_null<ContentCASMap*> const& content_cas_map,
-    std::filesystem::path const& fetch_dir,
-    gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
-    std::size_t jobs) -> ArchiveFetchMap {
+auto CreateArchiveFetchMap(gsl::not_null<ContentCASMap*> const& content_cas_map,
+                           std::filesystem::path const& fetch_dir,
+                           gsl::not_null<IExecutionApi const*> const& local_api,
+                           IExecutionApi::OptionalPtr const& remote_api,
+                           std::size_t jobs) -> ArchiveFetchMap {
     auto fetch_archive = [content_cas_map, fetch_dir, local_api, remote_api](
                              auto ts,
                              auto setter,
diff --git a/src/other_tools/ops_maps/archive_fetch_map.hpp b/src/other_tools/ops_maps/archive_fetch_map.hpp
index f6e3d987..9f0b220d 100644
--- a/src/other_tools/ops_maps/archive_fetch_map.hpp
+++ b/src/other_tools/ops_maps/archive_fetch_map.hpp
@@ -30,7 +30,7 @@ using ArchiveFetchMap = AsyncMapConsumer<ArchiveContent, bool>;
     gsl::not_null<ContentCASMap*> const& content_cas_map,
     std::filesystem::path const& fetch_dir,  // should exist!
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     std::size_t jobs) -> ArchiveFetchMap;
 
 #endif  // INCLUDED_SRC_OTHER_TOOLS_OPS_MAPS_ARCHIVE_FETCH_MAP_HPP
diff --git a/src/other_tools/ops_maps/content_cas_map.cpp b/src/other_tools/ops_maps/content_cas_map.cpp
index 4d1ca013..3cba65ef 100644
--- a/src/other_tools/ops_maps/content_cas_map.cpp
+++ b/src/other_tools/ops_maps/content_cas_map.cpp
@@ -110,7 +110,7 @@ auto CreateContentCASMap(
     gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
     std::optional<ServeApi> const& serve,
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     std::size_t jobs) -> ContentCASMap {
     auto ensure_in_cas = [just_mr_paths,
                           additional_mirrors,
diff --git a/src/other_tools/ops_maps/content_cas_map.hpp b/src/other_tools/ops_maps/content_cas_map.hpp
index 25facd07..df8b0103 100644
--- a/src/other_tools/ops_maps/content_cas_map.hpp
+++ b/src/other_tools/ops_maps/content_cas_map.hpp
@@ -86,7 +86,7 @@ using ContentCASMap = AsyncMapConsumer<ArchiveContent, std::nullptr_t>;
     gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
     std::optional<ServeApi> const& serve,
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     std::size_t jobs) -> ContentCASMap;
 
 namespace std {
diff --git a/src/other_tools/ops_maps/git_tree_fetch_map.cpp b/src/other_tools/ops_maps/git_tree_fetch_map.cpp
index c518c9e9..b08da28a 100644
--- a/src/other_tools/ops_maps/git_tree_fetch_map.cpp
+++ b/src/other_tools/ops_maps/git_tree_fetch_map.cpp
@@ -63,16 +63,15 @@ void BackupToRemote(std::string const& tree_id,
 
 /// \brief Moves the root tree from local CAS to the Git cache and sets the
 /// root.
-void MoveCASTreeToGit(
-    std::string const& tree_id,
-    ArtifactDigest const& digest,
-    gsl::not_null<ImportToGitMap*> const& import_to_git_map,
-    gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
-    bool backup_to_remote,
-    gsl::not_null<TaskSystem*> const& ts,
-    GitTreeFetchMap::SetterPtr const& setter,
-    GitTreeFetchMap::LoggerPtr const& logger) {
+void MoveCASTreeToGit(std::string const& tree_id,
+                      ArtifactDigest const& digest,
+                      gsl::not_null<ImportToGitMap*> const& import_to_git_map,
+                      gsl::not_null<IExecutionApi const*> const& local_api,
+                      IExecutionApi::OptionalPtr const& remote_api,
+                      bool backup_to_remote,
+                      gsl::not_null<TaskSystem*> const& ts,
+                      GitTreeFetchMap::SetterPtr const& setter,
+                      GitTreeFetchMap::LoggerPtr const& logger) {
     // Move tree from CAS to local Git storage
     auto tmp_dir = StorageConfig::CreateTypedTmpDir("fetch-remote-git-tree");
     if (not tmp_dir) {
@@ -131,7 +130,7 @@ auto CreateGitTreeFetchMap(
     std::vector<std::string> const& launcher,
     std::optional<ServeApi> const& serve,
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     bool backup_to_remote,
     std::size_t jobs) -> GitTreeFetchMap {
     auto tree_to_cache = [critical_git_op_map,
diff --git a/src/other_tools/ops_maps/git_tree_fetch_map.hpp b/src/other_tools/ops_maps/git_tree_fetch_map.hpp
index 82c858d5..be5a4252 100644
--- a/src/other_tools/ops_maps/git_tree_fetch_map.hpp
+++ b/src/other_tools/ops_maps/git_tree_fetch_map.hpp
@@ -62,7 +62,7 @@ using GitTreeFetchMap = AsyncMapConsumer<GitTreeInfo, bool>;
     std::vector<std::string> const& launcher,
     std::optional<ServeApi> const& serve,
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     bool backup_to_remote,
     std::size_t jobs) -> GitTreeFetchMap;
 
diff --git a/src/other_tools/root_maps/commit_git_map.cpp b/src/other_tools/root_maps/commit_git_map.cpp
index a4681a6a..a4f2b8eb 100644
--- a/src/other_tools/root_maps/commit_git_map.cpp
+++ b/src/other_tools/root_maps/commit_git_map.cpp
@@ -58,14 +58,13 @@ namespace {
 /// root if it was marked absent.
 /// It guarantees the logger is called exactly once with fatal on failure, and
 /// the setter on success.
-void EnsureRootAsAbsent(
-    std::string const& tree_id,
-    std::filesystem::path const& repo_root,
-    GitRepoInfo const& repo_info,
-    std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
-    CommitGitMap::SetterPtr const& ws_setter,
-    CommitGitMap::LoggerPtr const& logger) {
+void EnsureRootAsAbsent(std::string const& tree_id,
+                        std::filesystem::path const& repo_root,
+                        GitRepoInfo const& repo_info,
+                        std::optional<ServeApi> const& serve,
+                        IExecutionApi::OptionalPtr const& remote_api,
+                        CommitGitMap::SetterPtr const& ws_setter,
+                        CommitGitMap::LoggerPtr const& logger) {
     // this is an absent root
     if (serve) {
         // check if the serve endpoint has this root
@@ -401,23 +400,22 @@ void NetworkFetchAndSetPresentRoot(
 /// the root.
 /// It guarantees the logger is called exactly once with fatal on failure, and
 /// the setter on success.
-void EnsureCommit(
-    GitRepoInfo const& repo_info,
-    std::filesystem::path const& repo_root,
-    std::string const& fetch_repo,
-    MirrorsPtr const& additional_mirrors,
-    GitCASPtr const& git_cas,
-    gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
-    gsl::not_null<ImportToGitMap*> const& import_to_git_map,
-    std::string const& git_bin,
-    std::vector<std::string> const& launcher,
-    std::optional<ServeApi> const& serve,
-    gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
-    bool fetch_absent,
-    gsl::not_null<TaskSystem*> const& ts,
-    CommitGitMap::SetterPtr const& ws_setter,
-    CommitGitMap::LoggerPtr const& logger) {
+void EnsureCommit(GitRepoInfo const& repo_info,
+                  std::filesystem::path const& repo_root,
+                  std::string const& fetch_repo,
+                  MirrorsPtr const& additional_mirrors,
+                  GitCASPtr const& git_cas,
+                  gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
+                  gsl::not_null<ImportToGitMap*> const& import_to_git_map,
+                  std::string const& git_bin,
+                  std::vector<std::string> const& launcher,
+                  std::optional<ServeApi> const& serve,
+                  gsl::not_null<IExecutionApi const*> const& local_api,
+                  IExecutionApi::OptionalPtr const& remote_api,
+                  bool fetch_absent,
+                  gsl::not_null<TaskSystem*> const& ts,
+                  CommitGitMap::SetterPtr const& ws_setter,
+                  CommitGitMap::LoggerPtr const& logger) {
     // link fake repo to odb
     auto git_repo = GitRepoRemote::Open(git_cas);
     if (not git_repo) {
@@ -925,7 +923,7 @@ auto CreateCommitGitMap(
     std::vector<std::string> const& launcher,
     std::optional<ServeApi> const& serve,
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     bool fetch_absent,
     std::size_t jobs) -> CommitGitMap {
     auto commit_to_git = [critical_git_op_map,
diff --git a/src/other_tools/root_maps/commit_git_map.hpp b/src/other_tools/root_maps/commit_git_map.hpp
index d9f1a941..b76c1888 100644
--- a/src/other_tools/root_maps/commit_git_map.hpp
+++ b/src/other_tools/root_maps/commit_git_map.hpp
@@ -83,7 +83,7 @@ using CommitGitMap =
     std::vector<std::string> const& launcher,
     std::optional<ServeApi> const& serve,
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     bool fetch_absent,
     std::size_t jobs) -> CommitGitMap;
 
diff --git a/src/other_tools/root_maps/content_git_map.cpp b/src/other_tools/root_maps/content_git_map.cpp
index 4052b963..440593d0 100644
--- a/src/other_tools/root_maps/content_git_map.cpp
+++ b/src/other_tools/root_maps/content_git_map.cpp
@@ -52,14 +52,13 @@ namespace {
 /// root if it was marked absent.
 /// It guarantees the logger is called exactly once with fatal on failure, and
 /// the setter on success.
-void EnsureRootAsAbsent(
-    std::string const& tree_id,
-    ArchiveRepoInfo const& key,
-    std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
-    bool is_cache_hit,
-    ContentGitMap::SetterPtr const& ws_setter,
-    ContentGitMap::LoggerPtr const& logger) {
+void EnsureRootAsAbsent(std::string const& tree_id,
+                        ArchiveRepoInfo const& key,
+                        std::optional<ServeApi> const& serve,
+                        IExecutionApi::OptionalPtr const& remote_api,
+                        bool is_cache_hit,
+                        ContentGitMap::SetterPtr const& ws_setter,
+                        ContentGitMap::LoggerPtr const& logger) {
     // this is an absent root
     if (serve) {
         // check if the serve endpoint has this root
@@ -176,7 +175,7 @@ void ResolveContentTree(
     bool is_cache_hit,
     bool is_absent,
     std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
     gsl::not_null<ResolveSymlinksMap*> const& resolve_symlinks_map,
     gsl::not_null<TaskSystem*> const& ts,
@@ -365,7 +364,7 @@ void WriteIdFileAndSetWSRoot(
     std::filesystem::path const& archive_tree_id_file,
     bool is_absent,
     std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
     gsl::not_null<ResolveSymlinksMap*> const& resolve_symlinks_map,
     gsl::not_null<TaskSystem*> const& ts,
@@ -426,7 +425,7 @@ void ExtractAndImportToGit(
     std::filesystem::path const& archive_tree_id_file,
     bool is_absent,
     std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
     gsl::not_null<ImportToGitMap*> const& import_to_git_map,
     gsl::not_null<ResolveSymlinksMap*> const& resolve_symlinks_map,
@@ -510,7 +509,7 @@ auto CreateContentGitMap(
     gsl::not_null<ResolveSymlinksMap*> const& resolve_symlinks_map,
     gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
     std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     bool fetch_absent,
     std::size_t jobs) -> ContentGitMap {
     auto gitify_content = [content_cas_map,
diff --git a/src/other_tools/root_maps/content_git_map.hpp b/src/other_tools/root_maps/content_git_map.hpp
index d7f2c531..015895ec 100644
--- a/src/other_tools/root_maps/content_git_map.hpp
+++ b/src/other_tools/root_maps/content_git_map.hpp
@@ -44,7 +44,7 @@ using ContentGitMap =
     gsl::not_null<ResolveSymlinksMap*> const& resolve_symlinks_map,
     gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
     std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     bool fetch_absent,
     std::size_t jobs) -> ContentGitMap;
 
diff --git a/src/other_tools/root_maps/distdir_git_map.cpp b/src/other_tools/root_maps/distdir_git_map.cpp
index 94f923c1..f21994ba 100644
--- a/src/other_tools/root_maps/distdir_git_map.cpp
+++ b/src/other_tools/root_maps/distdir_git_map.cpp
@@ -134,7 +134,7 @@ auto CreateDistdirGitMap(
     gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
     std::optional<ServeApi> const& serve,
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     std::size_t jobs) -> DistdirGitMap {
     auto distdir_to_git = [content_cas_map,
                            import_to_git_map,
diff --git a/src/other_tools/root_maps/distdir_git_map.hpp b/src/other_tools/root_maps/distdir_git_map.hpp
index 1a350394..94ddbf9d 100644
--- a/src/other_tools/root_maps/distdir_git_map.hpp
+++ b/src/other_tools/root_maps/distdir_git_map.hpp
@@ -56,7 +56,7 @@ using DistdirGitMap =
     gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
     std::optional<ServeApi> const& serve,
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     std::size_t jobs) -> DistdirGitMap;
 
 namespace std {
diff --git a/src/other_tools/root_maps/fpath_git_map.cpp b/src/other_tools/root_maps/fpath_git_map.cpp
index 43cb0c24..3f941bf5 100644
--- a/src/other_tools/root_maps/fpath_git_map.cpp
+++ b/src/other_tools/root_maps/fpath_git_map.cpp
@@ -33,14 +33,13 @@ namespace {
 /// \brief Does the serve endpoint checks and sets the workspace root.
 /// It guarantees the logger is called exactly once with fatal on failure, and
 /// the setter on success.
-void CheckServeAndSetRoot(
-    std::string const& tree_id,
-    std::string const& repo_root,
-    bool absent,
-    std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
-    FilePathGitMap::SetterPtr const& ws_setter,
-    FilePathGitMap::LoggerPtr const& logger) {
+void CheckServeAndSetRoot(std::string const& tree_id,
+                          std::string const& repo_root,
+                          bool absent,
+                          std::optional<ServeApi> const& serve,
+                          IExecutionApi::OptionalPtr const& remote_api,
+                          FilePathGitMap::SetterPtr const& ws_setter,
+                          FilePathGitMap::LoggerPtr const& logger) {
     // if serve endpoint is given, try to ensure it has this tree available to
     // be able to build against it. If root is not absent, do not fail if we
     // don't have a suitable remote endpoint, but warn user nonetheless.
@@ -102,7 +101,7 @@ void ResolveFilePathTree(
     gsl::not_null<CriticalGitOpMap*> const& critical_git_op_map,
     gsl::not_null<ResolveSymlinksMap*> const& resolve_symlinks_map,
     std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     gsl::not_null<TaskSystem*> const& ts,
     FilePathGitMap::SetterPtr const& ws_setter,
     FilePathGitMap::LoggerPtr const& logger) {
@@ -256,7 +255,7 @@ auto CreateFilePathGitMap(
     gsl::not_null<ImportToGitMap*> const& import_to_git_map,
     gsl::not_null<ResolveSymlinksMap*> const& resolve_symlinks_map,
     std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     std::size_t jobs,
     std::string multi_repo_tool_name,
     std::string build_tool_name) -> FilePathGitMap {
diff --git a/src/other_tools/root_maps/fpath_git_map.hpp b/src/other_tools/root_maps/fpath_git_map.hpp
index a84ec947..f66413c0 100644
--- a/src/other_tools/root_maps/fpath_git_map.hpp
+++ b/src/other_tools/root_maps/fpath_git_map.hpp
@@ -55,7 +55,7 @@ using FilePathGitMap = AsyncMapConsumer<FpathInfo, nlohmann::json>;
     gsl::not_null<ImportToGitMap*> const& import_to_git_map,
     gsl::not_null<ResolveSymlinksMap*> const& resolve_symlinks_map,
     std::optional<ServeApi> const& serve,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     std::size_t jobs,
     std::string multi_repo_tool_name,
     std::string build_tool_name) -> FilePathGitMap;
diff --git a/src/other_tools/root_maps/root_utils.cpp b/src/other_tools/root_maps/root_utils.cpp
index efc4b6e0..1b9de917 100644
--- a/src/other_tools/root_maps/root_utils.cpp
+++ b/src/other_tools/root_maps/root_utils.cpp
@@ -35,13 +35,12 @@ auto CheckServeHasAbsentRoot(ServeApi const& serve,
     return std::nullopt;
 }
 
-auto EnsureAbsentRootOnServe(
-    ServeApi const& serve,
-    std::string const& tree_id,
-    std::filesystem::path const& repo_path,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
-    AsyncMapConsumerLoggerPtr const& logger,
-    bool no_sync_is_fatal) -> bool {
+auto EnsureAbsentRootOnServe(ServeApi const& serve,
+                             std::string const& tree_id,
+                             std::filesystem::path const& repo_path,
+                             IExecutionApi::OptionalPtr const& remote_api,
+                             AsyncMapConsumerLoggerPtr const& logger,
+                             bool no_sync_is_fatal) -> bool {
     if (remote_api) {
         // upload tree to remote CAS
         auto repo = RepositoryConfig{};
diff --git a/src/other_tools/root_maps/root_utils.hpp b/src/other_tools/root_maps/root_utils.hpp
index 7e47dc81..d444176c 100644
--- a/src/other_tools/root_maps/root_utils.hpp
+++ b/src/other_tools/root_maps/root_utils.hpp
@@ -58,7 +58,7 @@
     ServeApi const& serve,
     std::string const& tree_id,
     std::filesystem::path const& repo_path,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     AsyncMapConsumerLoggerPtr const& logger,
     bool no_sync_is_fatal) -> bool;
 
diff --git a/src/other_tools/root_maps/tree_id_git_map.cpp b/src/other_tools/root_maps/tree_id_git_map.cpp
index 5366ee86..690f756e 100644
--- a/src/other_tools/root_maps/tree_id_git_map.cpp
+++ b/src/other_tools/root_maps/tree_id_git_map.cpp
@@ -150,7 +150,7 @@ auto CreateTreeIdGitMap(
     bool fetch_absent,
     std::optional<ServeApi> const& serve,
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     std::size_t jobs) -> TreeIdGitMap {
     auto tree_to_git = [git_tree_fetch_map,
                         critical_git_op_map,
diff --git a/src/other_tools/root_maps/tree_id_git_map.hpp b/src/other_tools/root_maps/tree_id_git_map.hpp
index d9b7c1e4..d2a1c776 100644
--- a/src/other_tools/root_maps/tree_id_git_map.hpp
+++ b/src/other_tools/root_maps/tree_id_git_map.hpp
@@ -71,7 +71,7 @@ using TreeIdGitMap =
     bool fetch_absent,
     std::optional<ServeApi> const& serve,
     gsl::not_null<IExecutionApi const*> const& local_api,
-    std::optional<gsl::not_null<IExecutionApi const*>> const& remote_api,
+    IExecutionApi::OptionalPtr const& remote_api,
     std::size_t jobs) -> TreeIdGitMap;
 
 #endif  // INCLUDED_SRC_OTHER_TOOLS_ROOT_MAPS_TREE_ID_GIT_MAP_HPP
diff --git a/test/buildtool/execution_engine/executor/executor.test.cpp b/test/buildtool/execution_engine/executor/executor.test.cpp
index 26fd9b7d..b9772817 100644
--- a/test/buildtool/execution_engine/executor/executor.test.cpp
+++ b/test/buildtool/execution_engine/executor/executor.test.cpp
@@ -149,8 +149,8 @@ class TestApi : public IExecutionApi {
     [[nodiscard]] auto RetrieveToPaths(
         std::vector<Artifact::ObjectInfo> const& /*unused*/,
         std::vector<std::filesystem::path> const& /*unused*/,
-        std::optional<gsl::not_null<const IExecutionApi*>> const& /* unused */)
-        const noexcept -> bool final {
+        IExecutionApi::OptionalPtr const& /* unused */) const noexcept
+        -> bool final {
         return false;  // not needed by Executor
     }
     [[nodiscard]] auto RetrieveToFds(