diff --git a/.gitignore b/.gitignore
index 3daa17c..33948d1 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,3 @@
 *.elc
 tests/*.elc
+.etaf-build/
diff --git a/Makefile b/Makefile
index 779f989..d430222 100644
--- a/Makefile
+++ b/Makefile
@@ -1,10 +1,15 @@
 EMACS ?= emacs
 LOAD_PATH = -L . -L ../etaf -L ../etaf-ui -L ../ebox -L ../ecss -L ../tp -L ../etaf-sqlite
+EBOX_NATIVE_RELEASE_DIR = $(shell $(EMACS) -Q --batch $(LOAD_PATH) \
+	--eval '(setq load-prefer-newer t)' -l ../ebox/ebox-native-reflow.el \
+	--eval '(princ (expand-file-name (format "../ebox/native/target/%s/release/" (ebox-native-reflow--rust-target))))')
 ENTRY_EXAMPLES := $(wildcard examples/*.el)
 EXAMPLES := $(ENTRY_EXAMPLES)
 EXAMPLE_ELC := $(EXAMPLES:.el=.elc)
+TEST_FILES := $(wildcard tests/*-tests.el)
 
-.PHONY: all compile examples-read test perf check checkdoc load clean
+.PHONY: all compile examples-read test perf perf-evaluator perf-regressions \
+	perf-check check checkdoc load clean
 
 all: check
 
@@ -24,7 +29,7 @@ compile:
 		--eval '(dolist (file (quote ($(foreach file,$(ENTRY_EXAMPLES),"$(file)")))) (load-file file))' \
 		--eval '(dolist (file (quote ($(foreach file,$(EXAMPLES),"$(file)")))) (byte-compile-file file))' \
 		--eval '(byte-compile-file "etaf-playground.el")' \
-		--eval '(byte-compile-file "tests/etaf-playground-tests.el")'
+		--eval '(dolist (file (quote ($(foreach file,$(TEST_FILES),"$(file)")))) (byte-compile-file file))'
 
 examples-read: compile
 	$(EMACS) -Q --batch $(LOAD_PATH) --eval '(setq load-prefer-newer t)' \
@@ -34,18 +39,40 @@ examples-read: compile
 
 test: examples-read
 	$(EMACS) -Q --batch $(LOAD_PATH) --eval '(setq load-prefer-newer t)' \
-		-l tests/etaf-playground-tests.el -f ert-run-tests-batch-and-exit
+		$(foreach test,$(TEST_FILES),-l $(test)) -f ert-run-tests-batch-and-exit
 
-perf: compile
+perf: perf-evaluator
+
+perf-evaluator: compile
+	$(MAKE) -C ../ebox native-build EMACS="$(EMACS)" ECSS_DIR=../ecss TP_DIR=../tp
+	EBOX_NATIVE_REFLOW_MODULE_PATH="$(EBOX_NATIVE_RELEASE_DIR)" \
 	$(EMACS) -Q --batch $(LOAD_PATH) --eval '(setq load-prefer-newer t)' \
-		-l scripts/benchmark-research-shelf.el
+		--eval '(setq ebox-native-reflow-module-path (getenv "EBOX_NATIVE_REFLOW_MODULE_PATH"))' \
+		-l scripts/benchmark-research-shelf.el \
+		-f etaf-performance-evaluator-batch
+
+# Run package regressions in dependency order.  Keeping them in one recipe
+# prevents parallel make from cleaning/recompiling a sibling while another
+# package is loading its artifacts.
+perf-regressions:
+	$(MAKE) -C ../ecss test EMACS="$(EMACS)"
+	$(MAKE) -C ../tp test EMACS="$(EMACS)"
+	$(MAKE) -C ../ebox test EMACS="$(EMACS)" ECSS_DIR=../ecss TP_DIR=../tp
+	$(MAKE) -C ../etaf test EMACS="$(EMACS)"
+	$(MAKE) -C ../etaf-ui test EMACS="$(EMACS)"
+	$(MAKE) -C ../etaf-sqlite test EMACS="$(EMACS)"
+	$(MAKE) test EMACS="$(EMACS)"
+
+perf-check:
+	$(MAKE) perf-regressions EMACS="$(EMACS)"
+	$(MAKE) perf-evaluator EMACS="$(EMACS)"
 
 load: compile
 	$(EMACS) -Q --batch $(LOAD_PATH) --eval '(require (quote etaf-playground))' \
 		--eval '(princ "etaf-playground load OK\\n")'
 
 checkdoc:
-	$(EMACS) -Q --batch --eval '(progn (require (quote checkdoc)) (dolist (file (append (list "etaf-playground.el" "tests/etaf-playground-tests.el") (directory-files-recursively "examples" "\\.el$$"))) (checkdoc-file file)))'
+	$(EMACS) -Q --batch --eval '(progn (require (quote checkdoc)) (dolist (file (append (list "etaf-playground.el" "scripts/benchmark-research-shelf.el") (directory-files-recursively "tests" "\\.el$$") (directory-files-recursively "examples" "\\.el$$"))) (checkdoc-file file)))'
 
 check: checkdoc test
 
diff --git a/README.md b/README.md
index 06795d4..2afe168 100644
--- a/README.md
+++ b/README.md
@@ -19,6 +19,13 @@ into the right-hand preview. Saving a source file also refreshes by default.
 `etaf-playground-register-example` is available when a companion needs a
 non-conventional root or feature name.
 
+ETAF core provides the generic `M-x etaf-compile-app` and
+`M-x etaf-app-compile-status` commands; see the [ETAF
+documentation](../etaf/README.md) for the full contract. Playground does not
+implement compilation. It registers discovered examples as ETAF Apps and adds
+a `Compile App` shortcut plus status to the header line. Its default artifact
+directory is `.etaf-build/`.
+
 The low-level `etaf-playground-mount-example` API remains available for batch
 tests and consumers that only need a preview buffer. Business Components,
 database schemas, palettes, refs, and handlers stay in the example companion.
diff --git a/README.zh-CN.md b/README.zh-CN.md
index 47954e2..aa4b482 100644
--- a/README.zh-CN.md
+++ b/README.zh-CN.md
@@ -18,6 +18,11 @@ ETAF Playground 是通用的应用构建工作区：左侧编辑同一个应用
 也会刷新。若 root 或 feature 不遵循命名约定，可在 companion 中调用
 `etaf-playground-register-example` 注册覆盖。
 
+ETAF core 提供通用 App 预编译命令 `M-x etaf-compile-app` 和状态命令
+`M-x etaf-app-compile-status`；完整合同见 [ETAF 文档](../etaf/README.zh-CN.md)。
+Playground 不实现编译，只把发现的 example 注册成 ETAF App，并在 header line
+显示 `Compile App` 快捷按钮和当前状态。默认产物目录是 `.etaf-build/`。
+
 `etaf-playground-mount-example` 仍作为低层 batch/consumer API 保留。业务
 Component、数据库 schema、palette、refs 和 handlers 都应该留在 example companion
 中；Playground 只提供 source/preview 会话、读文件、窗口切换与生命周期。
diff --git a/etaf-playground.el b/etaf-playground.el
index 1c9479d..2c9475a 100644
--- a/etaf-playground.el
+++ b/etaf-playground.el
@@ -50,6 +50,13 @@
   :type 'directory
   :group 'etaf-playground)
 
+(defcustom etaf-playground-artifact-directory
+  (expand-file-name ".etaf-build"
+                    (file-name-directory (or load-file-name buffer-file-name)))
+  "Directory containing manually compiled `.etafc' App artifacts."
+  :type 'directory
+  :group 'etaf-playground)
+
 (defcustom etaf-playground-source-extensions
   '(".etaf" ".el" ".ecss")
   "Source extensions shown in a Playground workspace, in tab order."
@@ -201,6 +208,15 @@ the root factory."
          (specs (mapcar (lambda (name)
                           (etaf-playground--example-spec name directory))
                         (sort (delete-dups names) #'string<))))
+    (dolist (spec specs)
+      (etaf-register-app
+       (plist-get spec :pair)
+       :source (plist-get spec :el-file)
+       :static (plist-get spec :etaf-file)
+       :style (plist-get spec :ecss-file)
+       :artifact
+       (expand-file-name (concat (plist-get spec :pair) ".etafc")
+                         etaf-playground-artifact-directory)))
     (setq etaf-playground-scenario-manifest specs
           etaf-playground-example-names (mapcar (lambda (spec)
                                                   (plist-get spec :pair))
@@ -436,6 +452,11 @@ One-argument roots remain supported for small existing examples."
       (wrong-number-of-arguments
        (funcall root static-form)))))
 
+(defun etaf-playground--compiled-artifact (spec session)
+  "Return SPEC's validated compiled artifact, unless SESSION owns sources."
+  (unless session
+    (etaf-app-load-artifact-or-warn (plist-get spec :pair))))
+
 (defun etaf-playground-read-pair (name &optional session)
   "Load NAME's companion and return its root View value.
 
@@ -443,8 +464,13 @@ When SESSION is supplied, its current source buffers are authoritative.  The
 `.etaf' and `.ecss' files are read as inert data.  The `.el' companion is the
 only file evaluated by the framework."
   (let* ((spec (etaf-playground-scenario name))
-         (static-form (etaf-playground-read-static name session))
-         (ecss-form (etaf-playground-read-ecss name session)))
+         (artifact (etaf-playground--compiled-artifact spec session))
+         (static-form (if artifact
+                          (plist-get artifact :static-form)
+                        (etaf-playground-read-static name session)))
+         (ecss-form (if artifact
+                        (or (plist-get artifact :style-form) '(styles))
+                      (etaf-playground-read-ecss name session))))
     (etaf-playground--load-companion spec session)
     (etaf-playground--call-root
      (etaf-playground--root-factory spec)
@@ -466,11 +492,13 @@ only file evaluated by the framework."
     (setq-local truncate-lines nil))
   buffer)
 
-(defun etaf-playground-mount-example (buffer-name name &optional session)
+(defun etaf-playground-mount-example
+    (buffer-name name &optional session mount-options)
   "Mount example NAME into BUFFER-NAME and return its buffer.
 
 This is the low-level consumer API.  `etaf-playground-open-example' adds the
-source editors and side-by-side workspace around it."
+source editors and side-by-side workspace around it.  MOUNT-OPTIONS is
+forwarded to `etaf-mount', including an optional initial viewport."
   (let ((buffer (get-buffer-create buffer-name)))
     (when-let ((runtime (etaf-runtime-for-buffer buffer)))
       (with-current-buffer buffer
@@ -480,7 +508,8 @@ source editors and side-by-side workspace around it."
     ;; buffer-local display API cannot accidentally style the source editor
     ;; which invoked `etaf-playground-refresh'.
     (with-current-buffer buffer
-      (etaf-mount buffer (etaf-playground-read-pair name session)))
+      (etaf-mount buffer (etaf-playground-read-pair name session)
+                  mount-options))
     (with-current-buffer buffer
       (setq-local etaf-playground-current-example name))
     buffer))
@@ -630,8 +659,71 @@ the preview instead of destroying the source workspace."
                'help-echo (format "Switch to %s" extension)))))
         etaf-playground-source-extensions
         " | ")
+       "  "
+       (let* ((name (etaf-playground-session-name session))
+              (dirty
+               (cl-some (lambda (entry)
+                          (and (buffer-live-p (cdr entry))
+                               (buffer-modified-p (cdr entry))))
+                        (etaf-playground-session-source-buffers session)))
+              (status (unless dirty (etaf-app-compile-status name)))
+              (state (if dirty 'dirty (plist-get status :status))))
+         (concat
+          (make-text-button
+           " Compile App " nil
+           'action #'etaf-playground-compile-current-app
+           'follow-link t
+           'button-data name
+           'help-echo "Save sources and compile this App with ETAF")
+          " | "
+          (make-text-button
+           (format " %s " state) nil
+           'action #'etaf-playground-show-current-app-compile-status
+           'follow-link t
+           'button-data name
+           'help-echo "Show the generic ETAF App compilation status")))
        "  C-c C-c refresh"))))
 
+(defun etaf-playground--button-app-name (button)
+  "Return App name carried by header BUTTON."
+  (or (and (stringp button)
+           (get-text-property 0 'button-data button))
+      (and (fboundp 'button-get)
+           (ignore-errors (button-get button 'button-data)))
+      etaf-playground-current-example
+      (and (etaf-playground-session-p etaf-playground-session)
+           (etaf-playground-session-name etaf-playground-session))))
+
+;;;###autoload
+(defun etaf-playground-compile-current-app (&optional button)
+  "Compile BUTTON's App, or the current App, through generic ETAF APIs."
+  (interactive)
+  (let* ((name (etaf-playground--button-app-name button))
+         (session (and name (gethash name etaf-playground--sessions))))
+    (unless name (user-error "No ETAF App is associated with this buffer"))
+    (when (and session
+               (cl-some (lambda (entry)
+                          (and (buffer-live-p (cdr entry))
+                               (buffer-modified-p (cdr entry))))
+                        (etaf-playground-session-source-buffers session)))
+      (user-error "Save %s source buffers before compiling the App" name))
+    (let ((status (etaf-compile-app name)))
+      (when session (etaf-playground--refresh-source-headers session))
+      (message "Compiled ETAF App %s: %s"
+               name (plist-get status :file))
+      status)))
+
+;;;###autoload
+(defun etaf-playground-show-current-app-compile-status (&optional button)
+  "Show generic compile status for BUTTON's App or the current App."
+  (interactive)
+  (let* ((name (etaf-playground--button-app-name button))
+         (status (and name (etaf-app-compile-status name))))
+    (unless status (user-error "No ETAF App is associated with this buffer"))
+    (message "ETAF App %s: %s (%s)" name
+             (plist-get status :status) (plist-get status :file))
+    status))
+
 (defun etaf-playground--activate-source-tab (button)
   "Activate source tab BUTTON from a header-line text button."
   (let ((extension
@@ -893,7 +985,8 @@ batch tests and callers which do not need editor windows."
                          nil t)))
   (if buffer-name
       (etaf-playground--mount-for-display buffer-name name)
-    (let ((session (etaf-playground--make-session name)))
+    (let ((_artifact-status (etaf-app-load-artifact-or-warn name))
+          (session (etaf-playground--make-session name)))
       (etaf-playground--show-session session)
       (etaf-playground-refresh session)
       (etaf-playground--refresh-source-headers session)
diff --git a/examples/research-shelf.el b/examples/research-shelf.el
index 484e3b2..2794824 100644
--- a/examples/research-shelf.el
+++ b/examples/research-shelf.el
@@ -247,18 +247,22 @@ user's prior local additions cannot collide with the generated dataset."
   "Return stable identity for a reading ROW."
   (plist-get row :id))
 
-(defun etaf-research-shelf--create-model ()
-  "Create the Research Shelf model inside the owning Component Scope."
+(defun etaf-research-shelf--create-model (&optional initial-result)
+  "Create the Research Shelf model, optionally from INITIAL-RESULT."
   (let* ((database (etaf-research-shelf--ensure-database))
          (controller
           (etaf-data-controller
            (etaf-sqlite-source database)
            :page-size etaf-research-shelf-page-size
+           :initial-result initial-result
            :auto-load nil :item-key #'etaf-research-shelf--item-id
            :name 'etaf-research-shelf))
          (filter (etaf-ref 'all :name 'research-shelf-filter))
          (dark (etaf-ref nil :name 'research-shelf-dark-theme))
-         (toast (etaf-ref "Ready to read." :name 'research-shelf-toast)))
+         (toast (etaf-ref (if initial-result
+                              "✓ SQLite shelf ready"
+                            "Ready to read.")
+                          :name 'research-shelf-toast)))
     (list :database database
           :database-file etaf-research-shelf-database-file
           :controller controller :filter filter :dark dark :toast toast)))
@@ -407,10 +411,6 @@ user's prior local additions cannot collide with the generated dataset."
     (:key :kind :label "Kind" :width 7))
   "Compact DataGrid columns for the Research Shelf list.")
 
-(defun etaf-research-shelf--theme-value (key &optional default)
-  "Return inherited Research Shelf Theme token KEY or DEFAULT."
-  (etaf-theme-value key default))
-
 (defun etaf-research-shelf--static-child (form tag)
   "Return the first TAG child from inert FORM."
   (etaf-playground-static-child form tag))
@@ -462,16 +462,15 @@ user's prior local additions cannot collide with the generated dataset."
 
 (defun etaf-research-shelf--filter-view (model)
   "Return the filter rail for MODEL and inherited filter Context."
-  (let ((theme (etaf-theme-defaults)))
-    (etaf-view
-     (column :class "research-shelf-filter-rail" :width 'stretch :min-width 0
-             :flex-grow 1 :flex-shrink 1 :flex-basis '(220)
-             :padding '(1 1)
-             :border (plist-get theme :line)
-             :color (plist-get theme :ink)
-             :bgcolor (plist-get theme :panel)
+  (etaf-view
+   (column :class "research-shelf-filter-rail" :width 'stretch :min-width 0
+           :flex-grow 1 :flex-shrink 1 :flex-basis '(220)
+           :padding '(1 1)
+           :border (etaf-theme-token :line)
+           :color (etaf-theme-token :ink)
+           :bgcolor (etaf-theme-token :panel)
       (label :text "Library" :face 'bold)
-      (label :text "VIEWS" :color (plist-get theme :muted))
+      (label :text "VIEWS" :color (etaf-theme-token :muted))
       (etaf-research-shelf-filter-button
        :filter-key 'all :fallback "All" :ref 'research-shelf-filter-all)
       (etaf-research-shelf-filter-button
@@ -486,32 +485,31 @@ user's prior local additions cannot collide with the generated dataset."
        :filter-key 'starred :fallback "★ Starred"
        :ref 'research-shelf-filter-starred)
       (spacer :height 1)
-      (label :text "STORAGE" :color (plist-get theme :muted))
+      (label :text "STORAGE" :color (etaf-theme-token :muted))
       (label :text (file-name-nondirectory
                     (plist-get model :database-file)))
       (button :label "↻ Reload library" :ref 'research-shelf-reload
               :variant 'ghost
               :on-press (lambda ()
                           (etaf-dispatch 'etaf-research-shelf-reload
-                                         model)))))))
+                                         model))))))
 
 (defun etaf-research-shelf--reading-list-view (model form)
   "Return the reading list for MODEL and static MAIN FORM."
-  (let ((controller (etaf-research-shelf--controller model))
-        (theme (etaf-theme-defaults)))
+  (let ((controller (etaf-research-shelf--controller model)))
     (etaf-view
      (column :class "research-shelf-list" :width 'stretch :min-width 0
              :flex-grow 4 :flex-shrink 1 :flex-basis '(620)
              :padding '(1 2)
-             :border (plist-get theme :line)
-             :bgcolor (plist-get theme :panel)
+             :border (etaf-theme-token :line)
+             :bgcolor (etaf-theme-token :panel)
       (flex :width 'stretch :flex-wrap 'wrap :align-items 'center :gap '(1 (8))
        (column :flex-grow 1 :flex-shrink 1 :flex-basis '(0) :min-width 0
         (label :text (etaf-research-shelf--static-value
                       form :title "Reading queue") :face 'bold)
         (label :text (format "%d items · SQLite-backed"
                             (or (etaf-value (etaf-data-total controller)) 0))
-               :color (plist-get theme :muted)))
+               :color (etaf-theme-token :muted)))
        (number-input :label "Rows"
                      :value (etaf-value (etaf-data-page-size controller))
                      :ref 'research-shelf-page-size :min 1 :max 100
@@ -530,10 +528,6 @@ user's prior local additions cannot collide with the generated dataset."
        :row-ref (lambda (row)
                   (intern (format "research-shelf-row-%s"
                                   (etaf-research-shelf--item-id row))))
-       :row-selected-p
-       (lambda (row)
-         (etaf-data-selected-p controller
-                               (etaf-research-shelf--item-id row)))
        :on-row-press
        (lambda (row)
          (etaf-data-select-one controller
@@ -543,26 +537,25 @@ user's prior local additions cannot collide with the generated dataset."
       (etaf-pagination :controller controller
        :previous-ref 'research-shelf-page-previous
        :next-ref 'research-shelf-page-next
-       :color (plist-get theme :ink))))))
+       :color (etaf-theme-token :ink))))))
 
 (defun etaf-research-shelf--detail-view (model form)
   "Return the selected record inspector for MODEL and static FORM."
-  (let ((theme (etaf-theme-defaults)))
-    (etaf-view
+  (etaf-view
    (column :class "research-shelf-detail" :width 'stretch :min-width 0
            :flex-grow 2 :flex-shrink 1 :flex-basis '(340)
            :padding '(2 2)
-           :border (plist-get theme :line)
-           :bgcolor (plist-get theme :panel)
+           :border (etaf-theme-token :line)
+           :bgcolor (etaf-theme-token :panel)
     (label :text (etaf-research-shelf--static-value form :title
                                                      "Selected item")
-           :color (plist-get theme :accent))
+           :color (etaf-theme-token :accent))
     (text :face 'bold
      (expr :value
            (if-let ((row (etaf-research-shelf--selected model)))
                (plist-get row :title)
              "Choose a record")))
-    (text :color (plist-get theme :muted)
+    (text :color (etaf-theme-token :muted)
      (expr :value
            (if-let ((row (etaf-research-shelf--selected model)))
                (format "%s · %s" (plist-get row :author)
@@ -581,7 +574,7 @@ user's prior local additions cannot collide with the generated dataset."
                        (or (plist-get row :progress) 0)
                        (plist-get row :priority))
              "Progress  —  ·  Priority —")))
-    (text :color (plist-get theme :accent)
+    (text :color (etaf-theme-token :accent)
      (expr :value
            (let* ((row (etaf-research-shelf--selected model))
                   (progress (or (and row (plist-get row :progress)) 0))
@@ -589,13 +582,13 @@ user's prior local additions cannot collide with the generated dataset."
              (format "%s %s" (make-string filled ?█)
                      (make-string (- 10 filled) ?░)))))
     (spacer :height 1)
-    (text :color (plist-get theme :muted)
+    (text :color (etaf-theme-token :muted)
      (expr :value
            (if-let ((row (etaf-research-shelf--selected model)))
                (concat "“" (or (plist-get row :note) "No note yet.") "”")
              "Your notes and actions will appear here.")))
     (spacer :height 1)
-    (etaf-research-shelf-detail-actions)))))
+    (etaf-research-shelf-detail-actions))))
 
 (etaf-define-component etaf-research-shelf-detail-actions ()
   "Render selected-record actions from the inherited Research Shelf model."
@@ -649,11 +642,13 @@ user's prior local additions cannot collide with the generated dataset."
         (form (etaf-inject 'research-shelf-detail nil t)))
     (lambda () (etaf-research-shelf--detail-view model form))))
 
-(etaf-define-component etaf-research-shelf-shell (&key static-form)
+(etaf-define-component etaf-research-shelf-shell
+    (&key static-form initial-result)
   "Compose the Research Shelf app and provide its model/theme Context."
   :setup
   (let* ((static-form (etaf-current-prop :static-form))
-         (model (etaf-research-shelf--create-model))
+         (initial-result (etaf-current-prop :initial-result))
+         (model (etaf-research-shelf--create-model initial-result))
          (theme (etaf-computed
                  (lambda ()
                    (etaf-research-shelf--theme-defaults model))
@@ -663,41 +658,43 @@ user's prior local additions cannot collide with the generated dataset."
          (main (etaf-research-shelf--static-child static-form 'main))
          (library (etaf-research-shelf--static-child main 'library))
          (detail (etaf-research-shelf--static-child main 'detail)))
-    (etaf-on-mounted
-     (lambda ()
-       (etaf-research-shelf--load model "✓ SQLite shelf ready")))
+    (unless initial-result
+      (etaf-on-mounted
+       (lambda ()
+         (etaf-research-shelf--load model "✓ SQLite shelf ready"))))
     (etaf-theme-provide theme)
     (etaf-provide 'research-shelf-model model)
     (etaf-provide 'research-shelf-filters filters)
     (etaf-provide 'research-shelf-library library)
     (etaf-provide 'research-shelf-detail detail)
     (lambda ()
-      (let ((dark (etaf-value (plist-get model :dark))))
-        (etaf-view
-         (column :class "research-shelf-shell" :width '(viewport)
-                 :height '(viewport-height)
-                 :color (etaf-research-shelf--theme-value :ink)
-                 :bgcolor (etaf-research-shelf--theme-value :paper)
+      (etaf-view
+       (column :class "research-shelf-shell" :width '(viewport)
+               :height '(viewport-height)
+               :color (etaf-theme-token :ink)
+               :bgcolor (etaf-theme-token :paper)
           (flex :class "research-shelf-header" :width 'stretch :min-width 0
                 :flex-wrap 'wrap :align-items 'center :gap '(1 (10))
            (column :flex-grow 1 :flex-shrink 1 :flex-basis '(0) :min-width 0
             (label :text (etaf-research-shelf--static-value
                           header :eyebrow "Research Shelf")
-                   :color (etaf-research-shelf--theme-value :accent))
+                   :color (etaf-theme-token :accent))
             (label :text (etaf-research-shelf--static-value
                           static-form :title "Research Shelf") :face 'bold)
             (label :text (etaf-research-shelf--static-value
                           static-form :subtitle
                           "A quiet place for unfinished ideas")
-                   :color (etaf-research-shelf--theme-value :muted)))
+                   :color (etaf-theme-token :muted)))
            (column :width 'max-content :min-width 0
                    :flex-grow 0 :flex-shrink 0
             (checkbox :label "Dark" :ref 'research-shelf-theme-toggle
-                      :checked dark
+                      :checked (plist-get model :dark)
                       :on-change (lambda (value)
                                    (setf (etaf-value (plist-get model :dark)) value)
                                    (setf (etaf-value (plist-get model :toast))
-                                         (if value "Dark theme" "Light theme"))))))
+                                         (if value
+                                             "Dark theme"
+                                           "Light theme"))))))
           (flex :class "research-shelf-workspace" :width 'stretch
                 :flex-wrap 'wrap :align-items 'stretch :align-content 'start
                 :gap '(1 (6))
@@ -707,10 +704,10 @@ user's prior local additions cannot collide with the generated dataset."
           (flex :class "research-shelf-footer" :width 'stretch
                 :flex-wrap 'wrap :gap '(1 (8))
            (column :flex-grow 1 :flex-shrink 1 :flex-basis '(0) :min-width 0
-            (label :text (or (etaf-value (plist-get model :toast)) "Ready")))
+            (label :text (plist-get model :toast)))
            (label :text (file-name-nondirectory
                          (plist-get model :database-file))
-                  :color (etaf-research-shelf--theme-value :muted)))))))))
+                  :color (etaf-theme-token :muted))))))))
 
 ;;; ---------------------------------------------------------------------------
 ;;; ROOT / PLAYGROUND REGISTRATION
@@ -721,9 +718,17 @@ user's prior local additions cannot collide with the generated dataset."
   (unless (eq (car static-form) 'research-shelf-shell)
     (error "Unsupported Research Shelf static root: %S" static-form))
   (etaf-component-set-styles 'etaf-research-shelf-shell ecss-form)
-  (lambda ()
-    (etaf-view
-     (research-shelf-shell :static-form static-form))))
+  (let* ((database (etaf-research-shelf--ensure-database))
+         (initial-result
+          (condition-case nil
+              (etaf-data-source-load-page
+               (etaf-sqlite-source database)
+               nil 1 etaf-research-shelf-page-size)
+            (error nil))))
+    (lambda ()
+      (etaf-view
+       (research-shelf-shell
+        :static-form static-form :initial-result initial-result)))))
 
 (etaf-playground-register-example
  "research-shelf"
diff --git a/scripts/benchmark-research-shelf.el b/scripts/benchmark-research-shelf.el
index 4615111..cc7688f 100644
--- a/scripts/benchmark-research-shelf.el
+++ b/scripts/benchmark-research-shelf.el
@@ -1,93 +1,557 @@
-;;; benchmark-research-shelf.el --- Research Shelf latency gate -*- lexical-binding: t; -*-
+;;; benchmark-research-shelf.el --- Cross-package ETAF latency gate -*- lexical-binding: t; -*-
 
 ;;; Commentary:
-;; Reproducible fullscreen-equivalent warm interaction benchmark.  The process
-;; exits nonzero when the declared p50/max budgets are exceeded.
+;; Generic evaluator primitives exercised with Research Shelf as one fixed,
+;; deterministic, real cross-package workload.  Trace assertions consume only
+;; public `etaf-performance' records; application concepts stay out of the
+;; recorder itself.
 
 ;;; Code:
 (require 'cl-lib)
+(require 'seq)
 (require 'etaf-playground)
+(require 'etaf-performance)
 
-(defconst etaf-research-shelf-benchmark-row-p50-budget-ms 100.0)
-(defconst etaf-research-shelf-benchmark-row-max-budget-ms 250.0)
-(defconst etaf-research-shelf-benchmark-theme-p50-budget-ms 250.0)
-(defconst etaf-research-shelf-benchmark-theme-max-budget-ms 500.0)
+(defvar etaf-research-shelf-database-file)
+(defvar etaf-research-shelf-fixture-size)
+(defvar etaf-research-shelf-page-size)
+(declare-function etaf-research-shelf--ensure-database
+                  "../examples/research-shelf")
 
-(defun etaf-research-shelf-benchmark--percentile (samples percentile)
-  "Return PERCENTILE from numeric SAMPLES using nearest rank."
+(defconst etaf-performance-evaluator-sample-count 20)
+(defconst etaf-performance-evaluator-latency-budget-ms 50.0)
+(defconst etaf-performance-evaluator-scenario-budgets-ms
+  '(("theme-toggle" :p95 90.0 :max 110.0))
+  "User-approved scenario budgets overriding the default latency budget.")
+(defconst etaf-performance-evaluator-overhead-budget-ms 2.0)
+(defconst etaf-performance-evaluator-fixture-size 256)
+(defconst etaf-performance-evaluator-page-size 12)
+(defconst etaf-performance-evaluator-viewport-width 1413)
+(defconst etaf-performance-evaluator-viewport-height 62)
+
+(defun etaf-performance-evaluator--percentile (samples percentile)
+  "Return nearest-rank PERCENTILE from non-empty numeric SAMPLES."
+  (unless samples (error "Cannot summarize an empty performance sample"))
   (let* ((ordered (sort (copy-sequence samples) #'<))
-         (index (min (1- (length ordered))
-                     (floor (* percentile (length ordered))))))
-    (nth index ordered)))
+         (rank (max 1 (ceiling (* percentile (length ordered))))))
+    (nth (1- rank) ordered)))
 
-(defun etaf-research-shelf-benchmark--measure (runtime refs runs)
-  "Measure warm press events through RUNTIME while cycling REFS.
-The number of measured events is `RUNS'."
-  (cl-loop for index below runs
-           for ref = (nth (% index (length refs)) refs)
-           collect
-           (let ((started (float-time)))
-             (etaf-dispatch-event runtime ref 'press)
-             (* 1000.0 (- (float-time) started)))))
+(defun etaf-performance-evaluator--statistics (samples)
+  "Return min, p50, p95, and max statistics for SAMPLES."
+  (list :count (length samples) :min (apply #'min samples)
+        :p50 (etaf-performance-evaluator--percentile samples 0.50)
+        :p95 (etaf-performance-evaluator--percentile samples 0.95)
+        :max (apply #'max samples)))
 
-(defun etaf-research-shelf-benchmark--summary (label samples)
-  "Print and return LABEL summary for SAMPLES."
-  (let ((p50 (etaf-research-shelf-benchmark--percentile samples 0.5))
-        (maximum (apply #'max samples)))
-    (princ (format "%s p50=%.3fms max=%.3fms samples=%S\n"
-                   label p50 maximum samples))
-    (list :p50 p50 :max maximum)))
+(defun etaf-performance-evaluator--print-statistics (label statistics)
+  "Print LABEL and STATISTICS in stable machine-readable form."
+  (princ (format (concat "perf-scenario=%s samples=%d min=%.3fms "
+                         "p50=%.3fms p95=%.3fms max=%.3fms\n")
+                 label (plist-get statistics :count)
+                 (plist-get statistics :min) (plist-get statistics :p50)
+                 (plist-get statistics :p95) (plist-get statistics :max))))
 
-(defun etaf-research-shelf-benchmark-run ()
-  "Run the Research Shelf evaluator and return non-nil on success."
+(defun etaf-performance-evaluator--timed-call (function)
+  "Call FUNCTION and return `(ELAPSED-MS . RESULT)'."
+  (let ((started (float-time)) result)
+    (setq result (funcall function))
+    (cons (* 1000.0 (- (float-time) started)) result)))
+
+(cl-defun etaf-performance-evaluator--measure
+    (label action verify &key setup cleanup
+           (samples etaf-performance-evaluator-sample-count))
+  "Warm, then measure ACTION under LABEL and verify every result.
+ACTION, VERIFY, SETUP, and CLEANUP receive an index.  Warmup uses -1 and is
+never included in SAMPLES.  ACTION's result is passed to VERIFY and CLEANUP."
+  (let (durations)
+    (when setup (funcall setup -1))
+    ;; Batch Emacs does not run the interactive 0.2s deferred-GC timer between
+    ;; synthetic inputs.  Settle that idle work before, never inside, samples.
+    (garbage-collect)
+    (let ((result (funcall action -1)))
+      (funcall verify result -1)
+      (when cleanup (funcall cleanup result -1)))
+    (dotimes (index samples)
+      (when setup (funcall setup index))
+      (garbage-collect)
+      (pcase-let* ((`(,elapsed . ,result)
+                    (etaf-performance-evaluator--timed-call
+                     (lambda () (funcall action index)))))
+        (funcall verify result index)
+        (when cleanup (funcall cleanup result index))
+        (push elapsed durations)))
+    (let ((statistics
+           (etaf-performance-evaluator--statistics (nreverse durations))))
+      (etaf-performance-evaluator--print-statistics label statistics)
+      (cons label statistics))))
+
+(defun etaf-performance-evaluator--text (buffer)
+  "Return BUFFER's rendered text without properties."
+  (with-current-buffer buffer
+    (substring-no-properties (buffer-string))))
+
+(defun etaf-performance-evaluator--surface-invariant (runtime buffer label)
+  "Assert committed RUNTIME/publication invariants in BUFFER for LABEL."
+  (unless (and (buffer-live-p (get-buffer buffer))
+               (eq runtime (etaf-runtime-for-buffer buffer)))
+    (error "%s: mounted Runtime/buffer invariant failed" label))
+  (let ((generation (etaf-runtime-current-generation runtime)))
+    (unless (and (etaf-generation-p generation)
+                 (integerp (etaf-runtime-generation runtime))
+                 (> (etaf-runtime-generation runtime) 0)
+                 (integerp (etaf-generation-root-semantic-id generation))
+                 (etaf-runtime-handler-entries runtime)
+                 (etaf-runtime-host-props-entries runtime))
+      (error "%s: committed generation/publication structure is incomplete"
+             label)))
+  (unless (> (buffer-size (get-buffer buffer)) 0)
+    (error "%s: publication produced an empty visible buffer" label))
+  t)
+
+(defun etaf-performance-evaluator--load-workload ()
+  "Load the deterministic integration workload companion."
   (let* ((source (expand-file-name "examples/research-shelf.el"
-                                  default-directory))
-         (compiled (concat (file-name-sans-extension source) ".elc"))
-         (file (if (and (file-readable-p compiled)
-                        (not (file-newer-than-file-p source compiled)))
-                    compiled
-                  source)))
-    (load file nil nil t))
-  (let ((database (make-temp-file "etaf-research-shelf-perf-" nil ".sqlite"))
-        (buffer " *etaf-research-shelf-perf*"))
+                                   default-directory))
+         (compiled (concat (file-name-sans-extension source) ".elc")))
+    (load (if (and (file-readable-p compiled)
+                   (not (file-newer-than-file-p source compiled)))
+              compiled source)
+          nil nil t)))
+
+(defun etaf-performance-evaluator--prepare-database (database)
+  "Prepare DATABASE outside the measured mount operation."
+  (let ((etaf-research-shelf-database-file database)
+        (etaf-research-shelf-fixture-size
+         etaf-performance-evaluator-fixture-size)
+        (etaf-research-shelf-page-size etaf-performance-evaluator-page-size))
+    (etaf-research-shelf--ensure-database))
+  (unless (and (file-exists-p database)
+               (> (file-attribute-size (file-attributes database)) 0))
+    (error "Prepared SQLite fixture was not created: %s" database)))
+
+(defun etaf-performance-evaluator--verify-compiled-runtime (status)
+  "Require compiled App STATUS to include its native runtime accelerator."
+  (unless (and (eq (plist-get status :status) 'current)
+               (eq (plist-get status :runtime-accelerator) 'ready))
+    (error "Performance evaluator requires the compiled native runtime: %S"
+           status))
+  (princ "perf-runtime-accelerator=ready\n")
+  status)
+
+(defun etaf-performance-evaluator--verify-environment (environment)
+  "Require ENVIRONMENT to be suitable for an absolute latency gate."
+  (let* ((power (plist-get environment :power-state))
+         (source (or (plist-get power :source) 'unknown))
+         (low-power (or (plist-get power :low-power-mode) 'unknown))
+         (load (plist-get environment :load-average)))
+    (princ (format "perf-environment power-source=%s low-power-mode=%s load=%S\n"
+                   source low-power load))
+    (when (eq low-power 'on)
+      (error (concat "Performance evaluator requires low-power mode off; "
+                     "current source=%s")
+             source)))
+  environment)
+
+(defun etaf-performance-evaluator--mount (buffer)
+  "Mount the fixed workload in BUFFER at the fixed viewport."
+  (etaf-playground-mount-example
+   buffer "research-shelf" nil
+   (list :viewport-width etaf-performance-evaluator-viewport-width
+         :viewport-height etaf-performance-evaluator-viewport-height))
+  (etaf-runtime-for-buffer buffer))
+
+(defun etaf-performance-evaluator--close-buffer (buffer)
+  "Unmount and close BUFFER when it is live."
+  (when (get-buffer buffer) (etaf-playground-close buffer)))
+
+(defun etaf-performance-evaluator--visible-match-p (buffer regexp)
+  "Return non-nil when BUFFER's visible text matches REGEXP."
+  (string-match-p regexp (etaf-performance-evaluator--text buffer)))
+
+(defun etaf-performance-evaluator--trace-categories (records)
+  "Return unique stage categories present in performance RECORDS."
+  (let (categories)
+    (dolist (operation records)
+      (dolist (stage (etaf-performance-operation-stages operation))
+        (cl-pushnew (etaf-performance-stage-category stage) categories)))
+    categories))
+
+(defun etaf-performance-evaluator--verify-trace-records (records)
+  "Verify generic cross-package RECORDS are successful and complete."
+  (unless records (error "Trace-on run produced no etaf-performance records"))
+  (dolist (operation records)
+    (unless (eq (etaf-performance-operation-status operation) 'success)
+      (error "Trace operation %s (%s) finished with status %s"
+             (etaf-performance-operation-id operation)
+             (etaf-performance-operation-label operation)
+             (etaf-performance-operation-status operation)))
+    (dolist (stage (etaf-performance-operation-stages operation))
+      (unless (eq (etaf-performance-stage-status stage) 'success)
+        (error "Trace stage %s/%s finished with status %s"
+               (etaf-performance-stage-category stage)
+               (etaf-performance-stage-function stage)
+               (etaf-performance-stage-status stage)))))
+  (let ((categories (etaf-performance-evaluator--trace-categories records)))
+    (dolist (required '(runtime ebox tp sqlite))
+      (unless (memq required categories)
+        (error "Trace records lack required %s stage; present=%S"
+               required categories)))
+    (setq categories
+          (sort categories (lambda (left right)
+                             (string< (symbol-name left)
+                                      (symbol-name right)))))
+    (princ (format "perf-trace records=%d categories=%S status=success\n"
+                   (length records) categories))))
+
+(defun etaf-performance-evaluator--print-slowest-records (records)
+  "Print the two slowest generic operation RECORDS per kind/label."
+  (let ((groups (make-hash-table :test #'equal)) selected)
+    (dolist (operation records)
+      (let ((key (cons (etaf-performance-operation-kind operation)
+                       (etaf-performance-operation-label operation))))
+        (puthash key (cons operation (gethash key groups)) groups)))
+    (maphash
+     (lambda (_key operations)
+       (setq selected
+             (append
+              (seq-take
+               (sort operations
+                     (lambda (left right)
+                       (> (etaf-performance-operation-elapsed left)
+                          (etaf-performance-operation-elapsed right))))
+               2)
+              selected)))
+     groups)
+    (dolist
+        (operation
+         (sort selected
+               (lambda (left right)
+                 (> (etaf-performance-operation-elapsed left)
+                    (etaf-performance-operation-elapsed right)))))
+    (let* ((gc-count
+            (- (etaf-performance-operation-gc-count-after operation)
+               (etaf-performance-operation-gc-count-before operation)))
+           (gc-ms
+            (* 1000.0
+               (- (etaf-performance-operation-gc-elapsed-after operation)
+                  (etaf-performance-operation-gc-elapsed-before operation))))
+           (stages
+            (mapcar
+             (lambda (entry)
+               (cons (plist-get entry :category)
+                     (plist-get entry :exclusive-ms)))
+             (etaf-performance-operation-stage-summary operation)))
+           (ebox
+            (plist-get (etaf-performance-operation-metadata operation) :ebox)))
+      (princ
+       (format (concat "perf-slowest id=%d kind=%s label=%S elapsed=%.3fms "
+                       "gc=%d/%.3fms stages=%S ebox=%S\n")
+               (etaf-performance-operation-id operation)
+               (etaf-performance-operation-kind operation)
+               (etaf-performance-operation-label operation)
+               (etaf-performance-operation-elapsed operation)
+               gc-count gc-ms stages ebox))))))
+
+(defun etaf-performance-evaluator--select-ref (runtime ref)
+  "Select workload row REF through RUNTIME's public event path."
+  (etaf-dispatch-event runtime ref 'press)
+  ref)
+
+(defun etaf-performance-evaluator--measure-overhead (runtime buffer)
+  "Measure trace overhead for RUNTIME with visible state in BUFFER."
+  (let (signed-deltas absolute-deltas traced-samples plain-samples)
+    (dotimes (index etaf-performance-evaluator-sample-count)
+      (let ((order (if (zerop (% index 2)) '(nil t) '(t nil))) plain traced)
+        (dolist (trace-p order)
+          (etaf-performance-mode (if trace-p 1 -1))
+          ;; Restore equivalent state outside the timed region; AB/BA order
+          ;; cancels drift without retries or skipped real work.
+          (garbage-collect)
+          (etaf-focus runtime 'research-shelf-row-1)
+          (when trace-p (etaf-performance-clear))
+          (let ((before (etaf-focused-host-ref runtime))
+                (elapsed
+                 (let ((gc-cons-threshold most-positive-fixnum)
+                       (gc-cons-percentage 1.0))
+                   (car (etaf-performance-evaluator--timed-call
+                         (lambda () (etaf-focus-next runtime)))))))
+            (unless (and (buffer-live-p (get-buffer buffer))
+                         (not (equal before
+                                     (etaf-focused-host-ref runtime))))
+              (error "Trace-overhead: equivalent focus-navigation work failed"))
+            (if trace-p
+                (progn (setq traced elapsed)
+                       (unless (etaf-performance-records)
+                         (error "Trace-overhead: trace-on sample recorded nothing")))
+              (setq plain elapsed))))
+        (push plain plain-samples)
+        (push traced traced-samples)
+        (push (- traced plain) signed-deltas)
+        (push (abs (- traced plain)) absolute-deltas)))
+    (etaf-performance-mode -1)
+    (let ((signed
+           (etaf-performance-evaluator--statistics (nreverse signed-deltas)))
+          (jitter
+           (etaf-performance-evaluator--statistics
+            (nreverse absolute-deltas))))
+      (princ (format (concat "perf-trace-overhead pairs=%d off-p50=%.3fms "
+                             "on-p50=%.3fms signed-p50=%.3fms "
+                             "signed-p95=%.3fms jitter-p50=%.3fms "
+                             "budget=%.3fms\n")
+                     etaf-performance-evaluator-sample-count
+                     (etaf-performance-evaluator--percentile plain-samples .5)
+                     (etaf-performance-evaluator--percentile traced-samples .5)
+                     (plist-get signed :p50) (plist-get signed :p95)
+                     (plist-get jitter :p50)
+                     etaf-performance-evaluator-overhead-budget-ms))
+      (list :signed signed :jitter jitter))))
+
+(defun etaf-performance-evaluator--latency-failures (results)
+  "Return hard latency budget failures from scenario RESULTS."
+  (cl-loop for (label . statistics) in results append
+           (let* ((scenario
+                   (cdr (assoc label
+                               etaf-performance-evaluator-scenario-budgets-ms)))
+                  (p95-budget
+                   (or (plist-get scenario :p95)
+                       etaf-performance-evaluator-latency-budget-ms))
+                  (max-budget
+                   (or (plist-get scenario :max)
+                       etaf-performance-evaluator-latency-budget-ms))
+                 failures)
+             (when (> (plist-get statistics :p95)
+                      p95-budget)
+               (push (format "%s p95 %.3fms > %.3fms" label
+                             (plist-get statistics :p95)
+                             p95-budget)
+                     failures))
+             (when (> (plist-get statistics :max)
+                      max-budget)
+               (push (format "%s max %.3fms > %.3fms" label
+                             (plist-get statistics :max)
+                             max-budget)
+                     failures))
+             (nreverse failures))))
+
+(defun etaf-performance-evaluator-run ()
+  "Run the fixed cross-package evaluator and return non-nil on success."
+  (etaf-performance-evaluator--load-workload)
+  (etaf-performance-evaluator--verify-environment
+   (etaf-performance-environment-data))
+  (let* ((database (make-temp-file "etaf-perf-fixture-" nil ".sqlite"))
+         (buffer " *etaf-cross-package-perf*")
+         (mount-buffer " *etaf-cross-package-mount-perf*")
+         (etaf-research-shelf-database-file database)
+         (etaf-research-shelf-fixture-size
+          etaf-performance-evaluator-fixture-size)
+         (etaf-research-shelf-page-size etaf-performance-evaluator-page-size)
+         (etaf-performance-max-records 10000)
+         results runtime trace-records overhead failures)
     (unwind-protect
-        (let ((etaf-research-shelf-database-file database))
-          (ignore etaf-research-shelf-database-file)
-          (etaf-playground-open buffer)
-          (ebox-surface-update-buffer-viewport (get-buffer buffer) 1413 62)
-          (let ((runtime (etaf-runtime-for-buffer buffer)))
-            ;; Prewarm both structural states before collecting evidence.
-            (etaf-dispatch-event runtime 'research-shelf-row-1 'press)
-            (etaf-dispatch-event runtime 'research-shelf-row-2 'press)
-            (etaf-dispatch-event runtime 'research-shelf-theme-toggle 'press)
-            (etaf-dispatch-event runtime 'research-shelf-theme-toggle 'press)
-            (let* ((row (etaf-research-shelf-benchmark--summary
-                         "row-selection"
-                         (etaf-research-shelf-benchmark--measure
-                          runtime '(research-shelf-row-1 research-shelf-row-2) 8)))
-                   (theme (etaf-research-shelf-benchmark--summary
-                           "theme-toggle"
-                           (etaf-research-shelf-benchmark--measure
-                            runtime '(research-shelf-theme-toggle) 8)))
-                   (pass
-                    (and (<= (plist-get row :p50)
-                             etaf-research-shelf-benchmark-row-p50-budget-ms)
-                         (<= (plist-get row :max)
-                             etaf-research-shelf-benchmark-row-max-budget-ms)
-                         (<= (plist-get theme :p50)
-                             etaf-research-shelf-benchmark-theme-p50-budget-ms)
-                         (<= (plist-get theme :max)
-                             etaf-research-shelf-benchmark-theme-max-budget-ms))))
-              (princ (format "research-shelf-perf %s\n"
-                             (if pass "PASS" "FAIL")))
-              (unless pass
-                (error "Research Shelf interaction latency budget exceeded"))
-              t)))
-      (when (get-buffer buffer)
-        (etaf-playground-close buffer))
-      (when (file-exists-p database)
-        (delete-file database)))))
+        (progn
+          (etaf-performance-evaluator--prepare-database database)
+          ;; The maintained product path is a manually compiled App.  Compile
+          ;; and activate its optional native runtime before latency samples;
+          ;; compiler command latency remains visible through the generic
+          ;; compiler operation when users profile that command itself.
+          (etaf-performance-evaluator--verify-compiled-runtime
+           (etaf-compile-app "research-shelf"))
+          ;; Latency samples measure the product path without observer work.
+          ;; Trace behavior and overhead have separate, explicit gates below.
+          (etaf-performance-mode -1)
+          (etaf-performance-clear)
+          (push
+           (etaf-performance-evaluator--measure
+            "prepared-database-mount"
+            (lambda (_index)
+              (etaf-performance-evaluator--mount mount-buffer))
+            (lambda (mounted _index)
+              (etaf-performance-evaluator--surface-invariant
+               mounted mount-buffer "prepared-database-mount")
+              (let ((text (etaf-performance-evaluator--text mount-buffer)))
+                (unless (and (string-match-p "256 items · SQLite-backed" text)
+                             (string-match-p "Page 1 / 22" text))
+                  (error "Prepared-database-mount: fixture/page invariant failed"))))
+            :cleanup (lambda (_result _index)
+                       (etaf-performance-evaluator--close-buffer mount-buffer)))
+           results)
+          (setq runtime (etaf-performance-evaluator--mount buffer))
+          (etaf-performance-evaluator--surface-invariant runtime buffer "setup")
 
-(etaf-research-shelf-benchmark-run)
+          (push
+           (etaf-performance-evaluator--measure
+            "row-selection"
+            (lambda (index)
+              (let* ((ref (if (zerop (% (1+ index) 2))
+                              'research-shelf-row-1 'research-shelf-row-2))
+                     (before (etaf-runtime-generation runtime)))
+                (etaf-performance-evaluator--select-ref runtime ref)
+                (list ref before (etaf-runtime-generation runtime))))
+            (lambda (result _index)
+              (pcase-let ((`(,ref ,before ,after) result))
+                (unless (and (>= after before)
+                             (string-match-p
+                              "selected"
+                              (or (plist-get
+                                   (etaf-runtime-host-props-for runtime ref)
+                                   :class) "")))
+                  (error "Row-selection: selection/generation invariant failed")))
+              (etaf-performance-evaluator--surface-invariant
+               runtime buffer "row-selection")))
+           results)
 
+          (push
+           (etaf-performance-evaluator--measure
+            "theme-toggle"
+            (lambda (_index)
+              (let ((before (etaf-runtime-generation runtime)))
+                (etaf-dispatch-event runtime 'research-shelf-theme-toggle 'press)
+                (list before (etaf-runtime-generation runtime))))
+            (lambda (result _index)
+              (unless (and (> (cadr result) (car result))
+                           (etaf-performance-evaluator--visible-match-p
+                            buffer "\\(Dark theme\\|Light theme\\)"))
+                (error "Theme-toggle: theme/generation invariant failed"))
+              (etaf-performance-evaluator--surface-invariant
+               runtime buffer "theme-toggle")))
+           results)
+
+          (push
+           (etaf-performance-evaluator--measure
+            "filter-query"
+            (lambda (index)
+              (let* ((reading-p (zerop (% (1+ index) 2)))
+                     (ref (if reading-p 'research-shelf-filter-reading
+                            'research-shelf-filter-all))
+                     (before (etaf-runtime-generation runtime)))
+                (etaf-dispatch-event runtime ref 'press)
+                (list reading-p before (etaf-runtime-generation runtime))))
+            (lambda (result _index)
+              (unless (and (> (nth 2 result) (nth 1 result))
+                           (etaf-performance-evaluator--visible-match-p
+                            buffer (if (car result) "Showing Reading"
+                                     "Showing All")))
+                (error "Filter-query: query/generation invariant failed"))
+              (etaf-performance-evaluator--surface-invariant
+               runtime buffer "filter-query")))
+           results)
+
+          (etaf-dispatch-event runtime 'research-shelf-filter-all 'press)
+          (push
+           (etaf-performance-evaluator--measure
+            "pagination"
+            (lambda (_index)
+              (let* ((on-first (etaf-performance-evaluator--visible-match-p
+                                buffer "Page 1 / 22"))
+                     (ref (if on-first 'research-shelf-page-next
+                            'research-shelf-page-previous))
+                     (before (etaf-runtime-generation runtime)))
+                (etaf-dispatch-event runtime ref 'press)
+                (list (if on-first 2 1) before
+                      (etaf-runtime-generation runtime))))
+            (lambda (result _index)
+              (unless (and (> (nth 2 result) (nth 1 result))
+                           (etaf-performance-evaluator--visible-match-p
+                            buffer (format "Page %d / 22" (car result))))
+                (error "Pagination: page/generation invariant failed"))
+              (etaf-performance-evaluator--surface-invariant
+               runtime buffer "pagination")))
+           results)
+
+          (unless (etaf-performance-evaluator--visible-match-p
+                   buffer "Page 1 / 22")
+            (etaf-dispatch-event runtime 'research-shelf-page-previous 'press))
+          (let ((refs '(research-shelf-row-2 research-shelf-row-4
+                        research-shelf-row-5 research-shelf-row-8
+                        research-shelf-row-9 research-shelf-row-10)))
+            (push
+             (etaf-performance-evaluator--measure
+              "progress-mutation"
+              (lambda (_index)
+                (let ((before (etaf-runtime-generation runtime)))
+                  (etaf-dispatch-event runtime 'research-shelf-progress 'press)
+                  (list before (etaf-runtime-generation runtime))))
+              (lambda (result _index)
+                (unless (and (> (cadr result) (car result))
+                             (etaf-performance-evaluator--visible-match-p
+                              buffer "Progress saved"))
+                  (error "Progress-mutation: persistence invariant failed"))
+                (etaf-performance-evaluator--surface-invariant
+                 runtime buffer "progress-mutation"))
+              :setup (lambda (index)
+                       (etaf-performance-evaluator--select-ref
+                        runtime (nth (% (1+ index) (length refs)) refs))))
+             results))
+
+          (push
+           (etaf-performance-evaluator--measure
+            "focus-navigation"
+            (lambda (_index)
+              (let ((before (etaf-focused-host-ref runtime)))
+                (etaf-focus-next runtime)
+                (list before (etaf-focused-host-ref runtime))))
+            (lambda (result _index)
+              (unless (and (cadr result)
+                           (not (equal (car result) (cadr result))))
+                (error "Focus-navigation: focus did not advance"))
+              (etaf-performance-evaluator--surface-invariant
+               runtime buffer "focus-navigation")))
+           results)
+
+          ;; Capture one representative cross-package trace after the latency
+          ;; samples.  This validates coverage without folding observer work
+          ;; into the product latency distribution.
+          (etaf-performance-mode 1)
+          (etaf-performance-clear)
+          (etaf-performance-evaluator--select-ref
+           runtime 'research-shelf-row-1)
+          (etaf-performance-evaluator--select-ref
+           runtime 'research-shelf-row-2)
+          (etaf-dispatch-event runtime 'research-shelf-theme-toggle 'press)
+          (etaf-dispatch-event runtime 'research-shelf-theme-toggle 'press)
+          (etaf-dispatch-event runtime 'research-shelf-filter-reading 'press)
+          (etaf-dispatch-event runtime 'research-shelf-filter-all 'press)
+          (etaf-dispatch-event runtime 'research-shelf-page-next 'press)
+          (etaf-dispatch-event runtime 'research-shelf-page-previous 'press)
+          (etaf-performance-evaluator--select-ref
+           runtime 'research-shelf-row-2)
+          (etaf-dispatch-event runtime 'research-shelf-progress 'press)
+          (etaf-focus-next runtime)
+          (setq results (nreverse results)
+                trace-records (etaf-performance-records))
+          (etaf-performance-evaluator--verify-trace-records trace-records)
+          (etaf-performance-evaluator--print-slowest-records trace-records)
+          (etaf-performance-mode -1)
+          (setq overhead
+                (etaf-performance-evaluator--measure-overhead runtime buffer)
+                failures (etaf-performance-evaluator--latency-failures results))
+          (when (> (abs (plist-get (plist-get overhead :signed) :p50))
+                   etaf-performance-evaluator-overhead-budget-ms)
+            (push (format "trace signed |p50| %.3fms > %.3fms"
+                          (abs (plist-get (plist-get overhead :signed) :p50))
+                          etaf-performance-evaluator-overhead-budget-ms)
+                  failures))
+          (if failures
+              (let ((failure-count (length failures)))
+                (princ "etaf-cross-package-perf FAIL\n")
+                (dolist (failure (reverse failures))
+                  (princ (format "PERF-GATE-FAIL: %s\n" failure)))
+                (error "Cross-package performance gate failed (%d conditions)"
+                       failure-count))
+            (princ "etaf-cross-package-perf PASS\n") t))
+      (etaf-performance-mode -1)
+      (etaf-performance-evaluator--close-buffer mount-buffer)
+      (etaf-performance-evaluator--close-buffer buffer)
+      (when (file-exists-p database) (delete-file database)))))
+
+(defun etaf-performance-evaluator-batch ()
+  "Batch entry point for the cross-package performance evaluator."
+  (condition-case condition
+      (progn (etaf-performance-evaluator-run) (kill-emacs 0))
+    (error
+     (princ (format "PERF-EVALUATOR-ERROR: %s\n"
+                    (error-message-string condition)))
+     (kill-emacs 1))))
+
+(provide 'benchmark-research-shelf)
 ;;; benchmark-research-shelf.el ends here
diff --git a/tests/benchmark-research-shelf-tests.el b/tests/benchmark-research-shelf-tests.el
new file mode 100644
index 0000000..4c342cf
--- /dev/null
+++ b/tests/benchmark-research-shelf-tests.el
@@ -0,0 +1,93 @@
+;;; benchmark-research-shelf-tests.el --- Performance evaluator tests -*- lexical-binding: t; -*-
+
+;;; Code:
+(require 'ert)
+(load-file (expand-file-name "scripts/benchmark-research-shelf.el"
+                            default-directory))
+
+(declare-function etaf-performance-evaluator--percentile
+                  "../scripts/benchmark-research-shelf")
+(declare-function etaf-performance-evaluator--measure
+                  "../scripts/benchmark-research-shelf")
+(declare-function etaf-performance-evaluator--latency-failures
+                  "../scripts/benchmark-research-shelf")
+(declare-function etaf-performance-evaluator--verify-compiled-runtime
+                  "../scripts/benchmark-research-shelf")
+(declare-function etaf-performance-evaluator--verify-environment
+                  "../scripts/benchmark-research-shelf")
+
+(ert-deftest etaf-performance-evaluator-uses-nearest-rank-percentiles ()
+  "Return nearest-rank values for evaluator percentiles."
+  (let ((samples (number-sequence 1 20)))
+    (should (= 10 (etaf-performance-evaluator--percentile samples 0.50)))
+    (should (= 19 (etaf-performance-evaluator--percentile samples 0.95)))))
+
+(ert-deftest etaf-performance-evaluator-warms-before-exact-sample-count ()
+  "Execute one unmeasured warmup before the requested measured samples."
+  (let (actions verifications)
+    (let ((result
+           (etaf-performance-evaluator--measure
+            "unit-workload"
+            (lambda (index) (push index actions) index)
+            (lambda (value index)
+              (should (= value index))
+              (push index verifications))
+            :samples 3)))
+      (should (equal '(-1 0 1 2) (nreverse actions)))
+      (should (equal '(-1 0 1 2) (nreverse verifications)))
+      (should (= 3 (plist-get (cdr result) :count))))))
+
+(ert-deftest etaf-performance-evaluator-reports-both-hard-budget-failures ()
+  "Report p95 and max independently when both exceed the hard budget."
+  (let ((failures
+         (etaf-performance-evaluator--latency-failures
+          '((slow :count 20 :min 1.0 :p50 2.0 :p95 51.0 :max 60.0)))))
+    (should (= 2 (length failures)))
+    (should (string-match-p "slow p95" (car failures)))
+    (should (string-match-p "slow max" (cadr failures)))))
+
+(ert-deftest etaf-performance-evaluator-uses-approved-theme-budget ()
+  "Accept the approved 90ms Theme budget without relaxing other scenarios."
+  (should-not
+   (etaf-performance-evaluator--latency-failures
+    '(("theme-toggle" :count 20 :min 80.0 :p50 84.0
+                      :p95 86.0 :max 99.0))))
+  (should (= 2
+             (length
+              (etaf-performance-evaluator--latency-failures
+               '(("theme-toggle" :count 20 :min 80.0 :p50 84.0
+                                 :p95 91.0 :max 111.0)))))))
+
+(ert-deftest etaf-performance-evaluator-requires-native-compiled-runtime ()
+  "Never report fallback-renderer latency as the optimized product gate."
+  (cl-letf (((symbol-function 'princ) #'ignore))
+    (should
+     (equal
+      (etaf-performance-evaluator--verify-compiled-runtime
+       '(:status current :runtime-accelerator ready))
+      '(:status current :runtime-accelerator ready))))
+  (should-error
+   (etaf-performance-evaluator--verify-compiled-runtime
+    '(:status current :runtime-accelerator unavailable)))
+  (let ((makefile (with-temp-buffer
+                    (insert-file-contents "Makefile")
+                    (buffer-string))))
+    (should (string-match-p "native-build" makefile))
+    (should (string-match-p "EBOX_NATIVE_REFLOW_MODULE_PATH" makefile))))
+
+(ert-deftest etaf-performance-evaluator-rejects-low-power-baselines ()
+  "Absolute latency gates fail closed when macOS throttles the CPU."
+  (cl-letf (((symbol-function 'princ) #'ignore))
+    (should
+     (equal
+      '(:power-state (:source ac :low-power-mode off) :load-average (1.0))
+      (etaf-performance-evaluator--verify-environment
+       '(:power-state (:source ac :low-power-mode off)
+         :load-average (1.0)))))
+    (should-error
+     (etaf-performance-evaluator--verify-environment
+      '(:power-state (:source battery :low-power-mode on)
+        :load-average (1.0))))))
+
+(provide 'benchmark-research-shelf-tests)
+;;; benchmark-research-shelf-tests.el ends here
diff --git a/tests/etaf-playground-tests.el b/tests/etaf-playground-tests.el
index a0f0c68..fa88599 100644
--- a/tests/etaf-playground-tests.el
+++ b/tests/etaf-playground-tests.el
@@ -113,6 +113,23 @@ database and mounts a test buffer before running BODY."
                           "$(MAKE) -C ../etaf-sqlite compile"))
       (should (string-match-p (regexp-quote dependency) makefile)))))
 
+(ert-deftest etaf-playground-registers-app-for-interactive-compilation ()
+  "Discovered examples use the generic ETAF App compile/status commands."
+  (let ((directory (make-temp-file "etaf-playground-artifacts-" t)))
+    (unwind-protect
+        (let ((etaf-playground-artifact-directory directory))
+          (etaf-playground-refresh-examples)
+          (should (eq (plist-get (etaf-app-compile-status "research-shelf")
+                                 :status)
+                      'missing))
+          (let ((compiled (etaf-compile-app "research-shelf")))
+            (should (eq (plist-get compiled :status) 'current))
+            (should (> (plist-get compiled :blueprints) 0))
+            (should (file-readable-p (plist-get compiled :file)))))
+      (etaf-playground-refresh-examples)
+      (when (file-directory-p directory)
+        (delete-directory directory t)))))
+
 (ert-deftest etaf-playground-static-reader-is-inert-and-strict ()
   "Read pair structure as inert data and reject executable AST nodes."
   (let* ((form (etaf-playground-read-static "research-shelf"))
@@ -195,7 +212,8 @@ database and mounts a test buffer before running BODY."
                   (etaf-playground-session-preview-buffer
                    etaf-playground-session))))
         (let* ((header (etaf-playground--source-header))
-               (position (string-match " EL" header)))
+               (position (string-match " EL" header))
+               (compile-position (string-match "Compile App" header)))
           (should position)
           (should (get-text-property position 'button header))
           (should (equal ".el"
@@ -204,7 +222,12 @@ database and mounts a test buffer before running BODY."
            (propertize " EL " 'etaf-playground-extension ".el"))
           (should (equal ".el"
                          (etaf-playground-session-active-extension
-                          etaf-playground-session))))))))
+                          etaf-playground-session)))
+          (should compile-position)
+          (should (get-text-property compile-position 'button header))
+          (should (equal "research-shelf"
+                         (get-text-property compile-position
+                                            'button-data header))))))))
 
 (ert-deftest etaf-playground-direct-etaf-c-c-c-opens-workspace ()
   "The source render command opens a workspace for a directly opened `.etaf'."
@@ -278,6 +301,23 @@ database and mounts a test buffer before running BODY."
                  (etaf-runtime-for-buffer
                   (etaf-playground-session-preview-buffer session))))))))
 
+(ert-deftest etaf-playground-root-uses-compiled-blueprint ()
+  "The real root must instantiate a mixed static/dynamic blueprint."
+  (etaf-playground-test--with-app (buffer database)
+    (etaf-compiler-clear-cache)
+    (let* ((before (etaf-compiler-statistics))
+           (instantiations (plist-get before :instantiations))
+           (fallbacks (plist-get before :fallbacks))
+           (cache-entries (plist-get before :static-cache-entries)))
+      (etaf-playground-open buffer)
+      (let* ((after (etaf-compiler-statistics))
+             (blueprint (plist-get after :last-blueprint)))
+        (should (> (plist-get after :instantiations) instantiations))
+        (should (= (plist-get after :fallbacks) fallbacks))
+        (should (> (plist-get after :static-cache-entries) cache-entries))
+        (should (> (plist-get blueprint :dynamic-nodes) 0))
+        (should (> (plist-get blueprint :hole-count) 0))))))
+
 (ert-deftest etaf-playground-pair-mounts-sqlite-backed-surface ()
   "Mounting the pair initializes SQLite and renders the real app shell."
   (etaf-playground-test--with-app (buffer database)
@@ -448,14 +488,32 @@ database and mounts a test buffer before running BODY."
     (etaf-playground-open buffer)
     (let ((runtime (etaf-runtime-for-buffer buffer)))
       (etaf-dispatch-event runtime 'research-shelf-row-1 'press)
-      (dotimes (_ 4)
-        (etaf-dispatch-event runtime 'research-shelf-theme-toggle 'press))
+      (let (dark-output light-output)
+        (dotimes (cycle 2)
+          (etaf-dispatch-event runtime 'research-shelf-theme-toggle 'press)
+          (with-current-buffer buffer
+            (let ((output (buffer-substring (point-min) (point-max))))
+              (if (zerop cycle)
+                  (setq dark-output output)
+                (should (equal-including-properties output dark-output)))))
+        (etaf-dispatch-event runtime 'research-shelf-theme-toggle 'press)
+          (with-current-buffer buffer
+            (let ((output (buffer-substring (point-min) (point-max))))
+              (if (zerop cycle)
+                  (setq light-output output)
+                (should (equal-including-properties output light-output)))))))
       (should (string-match-p "The Shape of Tools"
                               (etaf-playground-test--text buffer)))
       (should (or (string-match-p "☑ Dark"
                                   (etaf-playground-test--text buffer))
                   (string-match-p "☐ Dark"
-                                  (etaf-playground-test--text buffer)))))
+                                  (etaf-playground-test--text buffer))))
+      ;; Theme-only Host reconstruction must preserve nested Component
+      ;; backend anchors for the next unrelated interaction.
+      (let ((generation (etaf-runtime-generation runtime)))
+        (etaf-dispatch-event runtime 'research-shelf-filter-reading 'press)
+        (should (= (etaf-runtime-generation runtime) (1+ generation)))
+        (should (eq runtime (etaf-runtime-for-buffer buffer)))))
     (etaf-playground-reset buffer)
     (should (etaf-runtime-p (etaf-runtime-for-buffer buffer))))
   (should-not (get-buffer " *etaf-research-shelf-test*")))