diff --git a/common/file_base.hh b/common/file_base.hh
index fd16a86..56bbb9b 100644
--- a/common/file_base.hh
+++ b/common/file_base.hh
@@ -1,5 +1,6 @@
 #pragma once
 
+#include <algorithm>
 #include <string_view>
 #include <vector>
 
@@ -12,24 +13,22 @@ class FileBase : public nf7::File {
  public:
   class Feature {
    public:
-    Feature() = default;
+    Feature() = delete;
+    Feature(nf7::FileBase& f) noexcept {
+      f.feats_.push_back(this);
+    }
     virtual ~Feature() = default;
     Feature(const Feature&) = delete;
     Feature(Feature&&) = delete;
     Feature& operator=(const Feature&) = delete;
     Feature& operator=(Feature&&) = delete;
 
-    // Feature* is just for avoiding multi inheritance issues with Env::Watcher
     virtual nf7::File* Find(std::string_view) const noexcept { return nullptr; }
     virtual void Handle(const nf7::File::Event&) noexcept { }
     virtual void Update() noexcept { }
   };
 
-  FileBase(const nf7::File::TypeInfo& t,
-           nf7::Env&                  env,
-           std::vector<Feature*>&&    feats = {}) noexcept :
-      nf7::File(t, env), feats_(std::move(feats)) {
-  }
+  using nf7::File::File;
 
   nf7::File* Find(std::string_view name) const noexcept override {
     for (auto feat : feats_) {
@@ -50,11 +49,6 @@ class FileBase : public nf7::File {
     }
   }
 
- protected:
-  void Install(Feature& f) noexcept {
-    feats_.push_back(&f);
-  }
-
  private:
   std::vector<Feature*> feats_;
 };
diff --git a/common/file_holder.hh b/common/file_holder.hh
index bb166cd..6118c3e 100644
--- a/common/file_holder.hh
+++ b/common/file_holder.hh
@@ -35,11 +35,12 @@ class FileHolder : public nf7::FileBase::Feature {
   using Entity = std::variant<
       std::monostate, nf7::File::Path, std::shared_ptr<nf7::File>>;
 
-  FileHolder(nf7::File& owner, std::string_view id,
+  FileHolder(nf7::FileBase& owner, std::string_view id,
              nf7::MutableMemento* mem = nullptr) noexcept :
+      nf7::FileBase::Feature(owner),
       owner_(&owner), mem_(mem), id_(id) {
   }
-  FileHolder(nf7::File& owner, std::string_view id,
+  FileHolder(nf7::FileBase& owner, std::string_view id,
              nf7::MutableMemento& mem) noexcept :
       FileHolder(owner, id, &mem) {
   }
diff --git a/common/gui_file.hh b/common/gui_file.hh
index 6b5d169..1b92312 100644
--- a/common/gui_file.hh
+++ b/common/gui_file.hh
@@ -55,7 +55,8 @@ class FileHolderEditor final : public nf7::FileBase::Feature {
     kRef,
   };
 
-  FileHolderEditor(nf7::FileHolder& h, FileFactory::Filter&& filter) noexcept :
+  FileHolderEditor(nf7::FileBase& f, nf7::FileHolder& h, FileFactory::Filter&& filter) noexcept :
+      nf7::FileBase::Feature(f),
       holder_(&h), factory_(h.owner(), std::move(filter)) {
   }
   FileHolderEditor(const FileHolderEditor&) = delete;
diff --git a/common/logger_ref.hh b/common/logger_ref.hh
index 4cc71cb..f677e8a 100644
--- a/common/logger_ref.hh
+++ b/common/logger_ref.hh
@@ -18,8 +18,8 @@ namespace nf7 {
 
 class LoggerRef final : public nf7::FileBase::Feature {
  public:
-  LoggerRef(nf7::File& f, nf7::File::Path&& p = {"_logger"}) noexcept :
-      file_(&f), path_(std::move(p)) {
+  LoggerRef(nf7::FileBase& f, nf7::File::Path&& p = {"_logger"}) noexcept :
+      nf7::FileBase::Feature(f), file_(&f), path_(std::move(p)) {
   }
   LoggerRef(const LoggerRef&) = default;
   LoggerRef(LoggerRef&&) = default;
diff --git a/common/nfile_watcher.hh b/common/nfile_watcher.hh
index 11ed453..1a5243a 100644
--- a/common/nfile_watcher.hh
+++ b/common/nfile_watcher.hh
@@ -12,7 +12,9 @@ namespace nf7 {
 
 class NFileWatcher final : public nf7::FileBase::Feature {
  public:
-  NFileWatcher() = default;
+  NFileWatcher() = delete;
+  NFileWatcher(nf7::FileBase& f) noexcept : nf7::FileBase::Feature(f) {
+  }
   NFileWatcher(const NFileWatcher&) = delete;
   NFileWatcher(NFileWatcher&&) = delete;
   NFileWatcher& operator=(const NFileWatcher&) = delete;
diff --git a/file/audio_device.cc b/file/audio_device.cc
index 52ba117..8b57f9c 100644
--- a/file/audio_device.cc
+++ b/file/audio_device.cc
@@ -100,7 +100,7 @@ class Device final : public nf7::FileBase, public nf7::DirItem, public nf7::Node
   };
 
   Device(nf7::Env& env, Data&& data = {}) noexcept :
-      nf7::FileBase(kType, env, {&log_}),
+      nf7::FileBase(kType, env),
       nf7::DirItem(nf7::DirItem::kMenu | nf7::DirItem::kTooltip),
       nf7::Node(nf7::Node::kNone),
       life_(*this), log_(*this), mem_(std::move(data), *this) {
diff --git a/file/font_face.cc b/file/font_face.cc
index 852b104..539d385 100644
--- a/file/font_face.cc
+++ b/file/font_face.cc
@@ -69,14 +69,14 @@ class FontFace final : public nf7::FileBase,
   };
 
   FontFace(nf7::Env& env, Data&& d = {}) noexcept :
-      nf7::FileBase(kType, env, {&nwatch_}),
+      nf7::FileBase(kType, env),
       nf7::DirItem(nf7::DirItem::kMenu |
                    nf7::DirItem::kTooltip),
       nf7::Node(nf7::Node::kNone),
       life_(*this),
+      nwatch_(*this),
       log_(std::make_shared<nf7::LoggerRef>(*this)),
       mem_(std::move(d), *this) {
-    nf7::FileBase::Install(*log_);
     mem_.onCommit = mem_.onRestore = nwatch_.onMod = [this]() {
       cache_ = std::nullopt;
     };
diff --git a/file/gl_obj.cc b/file/gl_obj.cc
index bde5ed6..e6555cb 100644
--- a/file/gl_obj.cc
+++ b/file/gl_obj.cc
@@ -95,17 +95,14 @@ class ObjBase : public nf7::FileBase,
   }
 
   ObjBase(nf7::Env& env, T&& data = {}) noexcept :
-      nf7::FileBase(TypeInfo::kType, env, {}),
+      nf7::FileBase(TypeInfo::kType, env),
       nf7::DirItem(nf7::DirItem::kMenu |
                    nf7::DirItem::kTooltip),
       nf7::Node(nf7::Node::kNone),
       life_(*this),
       log_(std::make_shared<nf7::LoggerRef>(*this)),
-      nwatch_(std::make_shared<nf7::NFileWatcher>()),
+      nwatch_(std::make_shared<nf7::NFileWatcher>(*this)),
       mem_(std::move(data), *this) {
-    nf7::FileBase::Install(*log_);
-    nf7::FileBase::Install(*nwatch_);
-
     nwatch_->onMod = mem_.onRestore = mem_.onCommit = [this]() {
       Drop();
     };
diff --git a/file/luajit_node.cc b/file/luajit_node.cc
index ba0610c..3a17138 100644
--- a/file/luajit_node.cc
+++ b/file/luajit_node.cc
@@ -62,15 +62,13 @@ class Node final : public nf7::FileBase, public nf7::DirItem, public nf7::Node {
   };
 
   Node(nf7::Env& env, Data&& data = {}) noexcept :
-      nf7::FileBase(kType, env, {}),
+      nf7::FileBase(kType, env),
       nf7::DirItem(nf7::DirItem::kMenu | nf7::DirItem::kWidget),
       nf7::Node(nf7::Node::kCustomNode),
       life_(*this),
       log_(std::make_shared<nf7::LoggerRef>(*this)),
       mem_(std::move(data), *this),
       importer_(std::make_shared<nf7::luajit::NFileImporter>(env.npath())) {
-    nf7::FileBase::Install(*log_);
-
     mem_.onCommit = mem_.onRestore = [this]() {
       cache_ = std::nullopt;
     };
diff --git a/file/node_ref.cc b/file/node_ref.cc
index eb1bac1..17235bc 100644
--- a/file/node_ref.cc
+++ b/file/node_ref.cc
@@ -62,8 +62,6 @@ class Ref final : public nf7::FileBase, public nf7::Node {
       life_(*this),
       log_(std::make_shared<nf7::LoggerRef>(*this)),
       mem_(std::move(data), *this) {
-    nf7::FileBase::Install(*log_);
-
     mem_.onRestore = mem_.onCommit = [this]() { SetUpWatcher(); };
   }
 
diff --git a/file/sequencer_adaptor.cc b/file/sequencer_adaptor.cc
index 1448f6c..9e27952 100644
--- a/file/sequencer_adaptor.cc
+++ b/file/sequencer_adaptor.cc
@@ -63,13 +63,13 @@ class Adaptor final : public nf7::FileBase, public nf7::Sequencer {
   };
 
   Adaptor(nf7::Env& env, Data&& data = {}) noexcept :
-      nf7::FileBase(kType, env, {&target_, &target_editor_}),
+      nf7::FileBase(kType, env),
       Sequencer(Sequencer::kCustomItem |
                 Sequencer::kTooltip |
                 Sequencer::kParamPanel),
       life_(*this),
       target_(*this, "target", mem_),
-      target_editor_(target_,
+      target_editor_(*this, target_,
                      [](auto& t) { return t.flags().contains("nf7::Sequencer"); }),
       mem_(std::move(data), *this) {
     mem_.data().target.SetTarget(target_);
diff --git a/file/sequencer_call.cc b/file/sequencer_call.cc
index f9290d7..ffa6913 100644
--- a/file/sequencer_call.cc
+++ b/file/sequencer_call.cc
@@ -48,13 +48,13 @@ class Call final : public nf7::FileBase, public nf7::Sequencer {
   };
 
   Call(nf7::Env& env, Data&& data = {}) noexcept :
-      FileBase(kType, env, {&callee_, &callee_editor_}),
+      nf7::FileBase(kType, env),
       Sequencer(Sequencer::kCustomItem |
                 Sequencer::kTooltip |
                 Sequencer::kParamPanel),
       life_(*this),
       callee_(*this, "callee", mem_),
-      callee_editor_(callee_,
+      callee_editor_(*this, callee_,
                      [](auto& t) { return t.flags().contains("nf7::Node"); }),
       mem_(std::move(data), *this) {
     mem_.data().callee.SetTarget(callee_);
diff --git a/file/sequencer_timeline.cc b/file/sequencer_timeline.cc
index a7d0c48..698f08c 100644
--- a/file/sequencer_timeline.cc
+++ b/file/sequencer_timeline.cc
@@ -69,7 +69,7 @@ class TL final : public nf7::FileBase, public nf7::DirItem, public nf7::Node {
      std::vector<std::unique_ptr<Layer>>&& layers = {},
      ItemId                                next   = 1,
      const nf7::gui::Window*               win    = nullptr) noexcept :
-      nf7::FileBase(kType, env, {&log_}),
+      nf7::FileBase(kType, env),
       nf7::DirItem(nf7::DirItem::kMenu | nf7::DirItem::kWidget),
       nf7::Node(nf7::Node::kMenu_DirItem),
       life_(*this), log_(*this),
diff --git a/file/system_event.cc b/file/system_event.cc
index a84c114..1d354d1 100644
--- a/file/system_event.cc
+++ b/file/system_event.cc
@@ -44,12 +44,12 @@ class Event final : public nf7::FileBase, public nf7::DirItem, public nf7::Node
   };
 
   Event(nf7::Env& env, Data&& data = {}) noexcept :
-      nf7::FileBase(kType, env, {&logger_, &handler_, &handler_editor_}),
+      nf7::FileBase(kType, env),
       nf7::DirItem(nf7::DirItem::kMenu | nf7::DirItem::kWidget),
       nf7::Node(nf7::Node::kMenu_DirItem),
       life_(*this), logger_(*this),
       handler_(*this, "handler", mem_),
-      handler_editor_(handler_,
+      handler_editor_(*this, handler_,
                       [](auto& t) { return t.flags().contains("nf7::Node"); }),
       la_root_(std::make_shared<nf7::Node::Lambda>(*this)),
       mem_(std::move(data)) {
diff --git a/file/system_logger.cc b/file/system_logger.cc
index a4e991f..34e4d7e 100644
--- a/file/system_logger.cc
+++ b/file/system_logger.cc
@@ -17,7 +17,6 @@
 #include "nf7.hh"
 
 #include "common/dir_item.hh"
-#include "common/file_base.hh"
 #include "common/generic_context.hh"
 #include "common/generic_memento.hh"
 #include "common/generic_type_info.hh"
@@ -111,7 +110,7 @@ class Logger final : public nf7::File,
   };
 
   Logger(nf7::Env& env, Data&& d = {}) noexcept :
-      File(kType, env), DirItem(DirItem::kMenu),
+      nf7::File(kType, env), DirItem(DirItem::kMenu),
       mem_(std::move(d), *this), win_(*this, "Log View") {
     win_.shown() = true;
 
diff --git a/file/system_nfile.cc b/file/system_nfile.cc
index 175a930..3fd00bd 100644
--- a/file/system_nfile.cc
+++ b/file/system_nfile.cc
@@ -112,16 +112,14 @@ class NFile final : public nf7::FileBase,
   };
 
   NFile(nf7::Env& env, Data&& data = {}) noexcept :
-      nf7::FileBase(kType, env, {&nwatch_}),
+      nf7::FileBase(kType, env),
       nf7::DirItem(nf7::DirItem::kMenu |
                    nf7::DirItem::kTooltip),
       nf7::Node(nf7::Node::kMenu_DirItem),
-      life_(*this),
+      life_(*this), nwatch_(*this),
       shared_(std::make_shared<SharedData>(*this)),
       th_(std::make_shared<Thread>(*this, Runner {shared_})),
       mem_(std::move(data), *this) {
-    nf7::FileBase::Install(shared_->log);
-
     mtx_.onLock   = [this]() { SetUp(); };
     mtx_.onUnlock = [this]() { shared_->nfile.reset(); };
 
diff --git a/file/value_plot.cc b/file/value_plot.cc
index e271211..7624e39 100644
--- a/file/value_plot.cc
+++ b/file/value_plot.cc
@@ -110,7 +110,7 @@ class Plot final : public nf7::FileBase,
   };
 
   Plot(nf7::Env& env, const nf7::gui::Window* win = nullptr, Data&& data = {}) noexcept :
-      nf7::FileBase(kType, env, {&log_}),
+      nf7::FileBase(kType, env),
       nf7::DirItem(nf7::DirItem::kMenu | nf7::DirItem::kWidget),
       nf7::Node(nf7::Node::kNone),
       life_(*this), log_(*this), win_(*this, "Plot", win), mem_(std::move(data)) {