diff --git a/shared/static/scripts/sx-browser.js b/shared/static/scripts/sx-browser.js
index fbd46a2..b29982b 100644
--- a/shared/static/scripts/sx-browser.js
+++ b/shared/static/scripts/sx-browser.js
@@ -14,7 +14,7 @@
   // =========================================================================
 
   var NIL = Object.freeze({ _nil: true, toString: function() { return "nil"; } });
-  var SX_VERSION = "2026-03-07T00:46:09Z";
+  var SX_VERSION = "2026-03-07T00:52:37Z";
 
   function isNil(x) { return x === NIL || x === null || x === undefined; }
   function isSxTruthy(x) { return x !== false && !isNil(x); }
@@ -515,6 +515,92 @@
     return NIL;
   }
 
+  // =========================================================================
+  // Platform: deps module — component dependency analysis
+  // =========================================================================
+
+  function componentDeps(c) {
+    return c.deps ? c.deps.slice() : [];
+  }
+
+  function componentSetDeps(c, deps) {
+    c.deps = deps;
+  }
+
+  function componentCssClasses(c) {
+    return c.cssClasses ? c.cssClasses.slice() : [];
+  }
+
+  function envComponents(env) {
+    var names = [];
+    for (var k in env) {
+      var v = env[k];
+      if (v && (v._component || v._macro)) names.push(k);
+    }
+    return names;
+  }
+
+  function regexFindAll(pattern, source) {
+    var re = new RegExp(pattern, "g");
+    var results = [];
+    var m;
+    while ((m = re.exec(source)) !== null) {
+      if (m[1] !== undefined) results.push(m[1]);
+      else results.push(m[0]);
+    }
+    return results;
+  }
+
+  function scanCssClasses(source) {
+    var classes = {};
+    var result = [];
+    var m;
+    var re1 = /:class\s+"([^"]*)"/g;
+    while ((m = re1.exec(source)) !== null) {
+      var parts = m[1].split(/\s+/);
+      for (var i = 0; i < parts.length; i++) {
+        if (parts[i] && !classes[parts[i]]) {
+          classes[parts[i]] = true;
+          result.push(parts[i]);
+        }
+      }
+    }
+    var re2 = /:class\s+\(str\s+((?:"[^"]*"\s*)+)\)/g;
+    while ((m = re2.exec(source)) !== null) {
+      var re3 = /"([^"]*)"/g;
+      var m2;
+      while ((m2 = re3.exec(m[1])) !== null) {
+        var parts2 = m2[1].split(/\s+/);
+        for (var j = 0; j < parts2.length; j++) {
+          if (parts2[j] && !classes[parts2[j]]) {
+            classes[parts2[j]] = true;
+            result.push(parts2[j]);
+          }
+        }
+      }
+    }
+    var re4 = /;;\s*@css\s+(.+)/g;
+    while ((m = re4.exec(source)) !== null) {
+      var parts3 = m[1].split(/\s+/);
+      for (var k = 0; k < parts3.length; k++) {
+        if (parts3[k] && !classes[parts3[k]]) {
+          classes[parts3[k]] = true;
+          result.push(parts3[k]);
+        }
+      }
+    }
+    return result;
+  }
+
+  function componentIoRefs(c) {
+    return c.ioRefs ? c.ioRefs.slice() : [];
+  }
+
+  function componentSetIoRefs(c, refs) {
+    c.ioRefs = refs;
+  }
+
+
   // =========================================================================
   // Platform interface — Parser
   // =========================================================================
@@ -2076,17 +2162,19 @@ return bindInlineHandlers(root); };
 
   // handle-popstate
   var handlePopstate = function(scrollY) { return (function() {
-  var boostEl = domQuery("[sx-boost]");
   var url = browserLocationHref();
-  return (isSxTruthy(boostEl) ? (function() {
-  var targetSel = domGetAttr(boostEl, "sx-boost");
-  var target = (isSxTruthy((isSxTruthy(targetSel) && !isSxTruthy((targetSel == "true")))) ? domQuery(targetSel) : NIL);
+  var boostEl = domQuery("[sx-boost]");
+  var targetSel = (isSxTruthy(boostEl) ? (function() {
+  var attr = domGetAttr(boostEl, "sx-boost");
+  return (isSxTruthy((isSxTruthy(attr) && !isSxTruthy((attr == "true")))) ? attr : NIL);
+})() : NIL);
+  var targetSel = sxOr(targetSel, "#main-panel");
+  var target = domQuery(targetSel);
   var pathname = urlPathname(url);
   return (isSxTruthy(target) ? (isSxTruthy(tryClientRoute(pathname, targetSel)) ? browserScrollTo(0, scrollY) : (function() {
   var headers = buildRequestHeaders(target, loadedComponentNames(), _cssHash);
   return fetchAndRestore(target, url, headers, scrollY);
 })()) : NIL);
-})() : NIL);
 })(); };
 
   // engine-init
@@ -2415,6 +2503,119 @@ callExpr.push(dictGet(kwargs, k)); } }
   var bootInit = function() { return (logInfo((String("sx-browser ") + String(SX_VERSION))), initCssTracking(), initStyleDict(), processPageScripts(), processSxScripts(NIL), sxHydrateElements(NIL), processElements(NIL)); };
 
 
+  // === Transpiled from deps (component dependency analysis) ===
+
+  // scan-refs
+  var scanRefs = function(node) { return (function() {
+  var refs = [];
+  scanRefsWalk(node, refs);
+  return refs;
+})(); };
+
+  // scan-refs-walk
+  var scanRefsWalk = function(node, refs) { return (isSxTruthy((typeOf(node) == "symbol")) ? (function() {
+  var name = symbolName(node);
+  return (isSxTruthy(startsWith(name, "~")) ? (isSxTruthy(!isSxTruthy(contains(refs, name))) ? append_b(refs, name) : NIL) : NIL);
+})() : (isSxTruthy((typeOf(node) == "list")) ? forEach(function(item) { return scanRefsWalk(item, refs); }, node) : (isSxTruthy((typeOf(node) == "dict")) ? forEach(function(key) { return scanRefsWalk(dictGet(node, key), refs); }, keys(node)) : NIL))); };
+
+  // transitive-deps-walk
+  var transitiveDepsWalk = function(n, seen, env) { return (isSxTruthy(!isSxTruthy(contains(seen, n))) ? (append_b(seen, n), (function() {
+  var val = envGet(env, n);
+  return (isSxTruthy((typeOf(val) == "component")) ? forEach(function(ref) { return transitiveDepsWalk(ref, seen, env); }, scanRefs(componentBody(val))) : (isSxTruthy((typeOf(val) == "macro")) ? forEach(function(ref) { return transitiveDepsWalk(ref, seen, env); }, scanRefs(macroBody(val))) : NIL));
+})()) : NIL); };
+
+  // transitive-deps
+  var transitiveDeps = function(name, env) { return (function() {
+  var seen = [];
+  var key = (isSxTruthy(startsWith(name, "~")) ? name : (String("~") + String(name)));
+  transitiveDepsWalk(key, seen, env);
+  return filter(function(x) { return !isSxTruthy((x == key)); }, seen);
+})(); };
+
+  // compute-all-deps
+  var computeAllDeps = function(env) { return forEach(function(name) { return (function() {
+  var val = envGet(env, name);
+  return (isSxTruthy((typeOf(val) == "component")) ? componentSetDeps(val, transitiveDeps(name, env)) : NIL);
+})(); }, envComponents(env)); };
+
+  // scan-components-from-source
+  var scanComponentsFromSource = function(source) { return (function() {
+  var matches = regexFindAll("\\(~([a-zA-Z_][a-zA-Z0-9_\\-]*)", source);
+  return map(function(m) { return (String("~") + String(m)); }, matches);
+})(); };
+
+  // components-needed
+  var componentsNeeded = function(pageSource, env) { return (function() {
+  var direct = scanComponentsFromSource(pageSource);
+  var allNeeded = [];
+  { var _c = direct; for (var _i = 0; _i < _c.length; _i++) { var name = _c[_i]; if (isSxTruthy(!isSxTruthy(contains(allNeeded, name)))) {
+  allNeeded.push(name);
+}
+(function() {
+  var val = envGet(env, name);
+  return (function() {
+  var deps = (isSxTruthy((isSxTruthy((typeOf(val) == "component")) && !isSxTruthy(isEmpty(componentDeps(val))))) ? componentDeps(val) : transitiveDeps(name, env));
+  return forEach(function(dep) { return (isSxTruthy(!isSxTruthy(contains(allNeeded, dep))) ? append_b(allNeeded, dep) : NIL); }, deps);
+})();
+})(); } }
+  return allNeeded;
+})(); };
+
+  // page-component-bundle
+  var pageComponentBundle = function(pageSource, env) { return componentsNeeded(pageSource, env); };
+
+  // page-css-classes
+  var pageCssClasses = function(pageSource, env) { return (function() {
+  var needed = componentsNeeded(pageSource, env);
+  var classes = [];
+  { var _c = needed; for (var _i = 0; _i < _c.length; _i++) { var name = _c[_i]; (function() {
+  var val = envGet(env, name);
+  return (isSxTruthy((typeOf(val) == "component")) ? forEach(function(cls) { return (isSxTruthy(!isSxTruthy(contains(classes, cls))) ? append_b(classes, cls) : NIL); }, componentCssClasses(val)) : NIL);
+})(); } }
+  { var _c = scanCssClasses(pageSource); for (var _i = 0; _i < _c.length; _i++) { var cls = _c[_i]; if (isSxTruthy(!isSxTruthy(contains(classes, cls)))) {
+  classes.push(cls);
+} } }
+  return classes;
+})(); };
+
+  // scan-io-refs-walk
+  var scanIoRefsWalk = function(node, ioNames, refs) { return (isSxTruthy((typeOf(node) == "symbol")) ? (function() {
+  var name = symbolName(node);
+  return (isSxTruthy(contains(ioNames, name)) ? (isSxTruthy(!isSxTruthy(contains(refs, name))) ? append_b(refs, name) : NIL) : NIL);
+})() : (isSxTruthy((typeOf(node) == "list")) ? forEach(function(item) { return scanIoRefsWalk(item, ioNames, refs); }, node) : (isSxTruthy((typeOf(node) == "dict")) ? forEach(function(key) { return scanIoRefsWalk(dictGet(node, key), ioNames, refs); }, keys(node)) : NIL))); };
+
+  // scan-io-refs
+  var scanIoRefs = function(node, ioNames) { return (function() {
+  var refs = [];
+  scanIoRefsWalk(node, ioNames, refs);
+  return refs;
+})(); };
+
+  // transitive-io-refs-walk
+  var transitiveIoRefsWalk = function(n, seen, allRefs, env, ioNames) { return (isSxTruthy(!isSxTruthy(contains(seen, n))) ? (append_b(seen, n), (function() {
+  var val = envGet(env, n);
+  return (isSxTruthy((typeOf(val) == "component")) ? (forEach(function(ref) { return (isSxTruthy(!isSxTruthy(contains(allRefs, ref))) ? append_b(allRefs, ref) : NIL); }, scanIoRefs(componentBody(val), ioNames)), forEach(function(dep) { return transitiveIoRefsWalk(dep, seen, allRefs, env, ioNames); }, scanRefs(componentBody(val)))) : (isSxTruthy((typeOf(val) == "macro")) ? (forEach(function(ref) { return (isSxTruthy(!isSxTruthy(contains(allRefs, ref))) ? append_b(allRefs, ref) : NIL); }, scanIoRefs(macroBody(val), ioNames)), forEach(function(dep) { return transitiveIoRefsWalk(dep, seen, allRefs, env, ioNames); }, scanRefs(macroBody(val)))) : NIL));
+})()) : NIL); };
+
+  // transitive-io-refs
+  var transitiveIoRefs = function(name, env, ioNames) { return (function() {
+  var allRefs = [];
+  var seen = [];
+  var key = (isSxTruthy(startsWith(name, "~")) ? name : (String("~") + String(name)));
+  transitiveIoRefsWalk(key, seen, allRefs, env, ioNames);
+  return allRefs;
+})(); };
+
+  // compute-all-io-refs
+  var computeAllIoRefs = function(env, ioNames) { return forEach(function(name) { return (function() {
+  var val = envGet(env, name);
+  return (isSxTruthy((typeOf(val) == "component")) ? componentSetIoRefs(val, transitiveIoRefs(name, env, ioNames)) : NIL);
+})(); }, envComponents(env)); };
+
+  // component-pure?
+  var componentPure_p = function(name, env, ioNames) { return isEmpty(transitiveIoRefs(name, env, ioNames)); };
+
+
   // === Transpiled from router (client-side route matching) ===
 
   // split-path-segments
@@ -3137,9 +3338,12 @@ callExpr.push(dictGet(kwargs, k)); } }
     link.addEventListener("click", function(e) {
       e.preventDefault();
       var pathname = urlPathname(href);
-      // Find the sx-boost target selector from the link's ancestor
+      // Find target selector: sx-boost ancestor, explicit sx-target, or #main-panel
       var boostEl = link.closest("[sx-boost]");
       var targetSel = boostEl ? boostEl.getAttribute("sx-boost") : null;
+      if (!targetSel || targetSel === "true") {
+        targetSel = link.getAttribute("sx-target") || "#main-panel";
+      }
       if (tryClientRoute(pathname, targetSel)) {
         try { history.pushState({ sxUrl: href, scrollY: window.scrollY }, "", href); } catch (err) {}
         if (typeof window !== "undefined") window.scrollTo(0, 0);
@@ -3663,6 +3867,16 @@ callExpr.push(dictGet(kwargs, k)); } }
     renderComponent: typeof sxRenderComponent === "function" ? sxRenderComponent : null,
     getEnv: function() { return componentEnv; },
     init: typeof bootInit === "function" ? bootInit : null,
+    scanRefs: scanRefs,
+    transitiveDeps: transitiveDeps,
+    computeAllDeps: computeAllDeps,
+    componentsNeeded: componentsNeeded,
+    pageComponentBundle: pageComponentBundle,
+    pageCssClasses: pageCssClasses,
+    scanIoRefs: scanIoRefs,
+    transitiveIoRefs: transitiveIoRefs,
+    computeAllIoRefs: computeAllIoRefs,
+    componentPure_p: componentPure_p,
     splitPathSegments: splitPathSegments,
     parseRoutePattern: parseRoutePattern,
     matchRoute: matchRoute,
diff --git a/shared/sx/ref/bootstrap_js.py b/shared/sx/ref/bootstrap_js.py
index 4d9595a..37c0425 100644
--- a/shared/sx/ref/bootstrap_js.py
+++ b/shared/sx/ref/bootstrap_js.py
@@ -2616,9 +2616,12 @@ PLATFORM_ORCHESTRATION_JS = """
     link.addEventListener("click", function(e) {
       e.preventDefault();
       var pathname = urlPathname(href);
-      // Find the sx-boost target selector from the link's ancestor
+      // Find target selector: sx-boost ancestor, explicit sx-target, or #main-panel
       var boostEl = link.closest("[sx-boost]");
       var targetSel = boostEl ? boostEl.getAttribute("sx-boost") : null;
+      if (!targetSel || targetSel === "true") {
+        targetSel = link.getAttribute("sx-target") || "#main-panel";
+      }
       if (tryClientRoute(pathname, targetSel)) {
         try { history.pushState({ sxUrl: href, scrollY: window.scrollY }, "", href); } catch (err) {}
         if (typeof window !== "undefined") window.scrollTo(0, 0);
diff --git a/shared/sx/ref/orchestration.sx b/shared/sx/ref/orchestration.sx
index 550d534..3906556 100644
--- a/shared/sx/ref/orchestration.sx
+++ b/shared/sx/ref/orchestration.sx
@@ -829,22 +829,24 @@
 (define handle-popstate
   (fn (scrollY)
     ;; Handle browser back/forward navigation.
-    ;; Derive target from the nearest [sx-boost] container.
+    ;; Derive target from [sx-boost] container or fall back to #main-panel.
     ;; Try client-side route first, fall back to server fetch.
-    (let ((boost-el (dom-query "[sx-boost]"))
-          (url (browser-location-href)))
-      (when boost-el
-        (let ((target-sel (dom-get-attr boost-el "sx-boost"))
-              (target (if (and target-sel (not (= target-sel "true")))
-                        (dom-query target-sel)
+    (let ((url (browser-location-href))
+          (boost-el (dom-query "[sx-boost]"))
+          (target-sel (if boost-el
+                        (let ((attr (dom-get-attr boost-el "sx-boost")))
+                          (if (and attr (not (= attr "true"))) attr nil))
                         nil))
-              (pathname (url-pathname url)))
-          (when target
-            (if (try-client-route pathname target-sel)
-              (browser-scroll-to 0 scrollY)
-              (let ((headers (build-request-headers target
-                               (loaded-component-names) _css-hash)))
-                (fetch-and-restore target url headers scrollY)))))))))
+          ;; Fall back to #main-panel if no sx-boost target
+          (target-sel (or target-sel "#main-panel"))
+          (target (dom-query target-sel))
+          (pathname (url-pathname url)))
+      (when target
+        (if (try-client-route pathname target-sel)
+          (browser-scroll-to 0 scrollY)
+          (let ((headers (build-request-headers target
+                           (loaded-component-names) _css-hash)))
+            (fetch-and-restore target url headers scrollY)))))))
 
 
 ;; --------------------------------------------------------------------------