diff --git a/config/ext.json b/config/ext.json
index af3c48bc..1cf99d1f 100644
--- a/config/ext.json
+++ b/config/ext.json
@@ -370,6 +370,9 @@
         "ext-depends": [
             "zlib",
             "session"
+        ],
+        "shared-ext-depends": [
+            "session"
         ]
     },
     "memcached": {
@@ -388,6 +391,9 @@
         "ext-depends": [
             "session",
             "zlib"
+        ],
+        "shared-ext-depends": [
+            "session"
         ]
     },
     "mongodb": {
@@ -692,7 +698,8 @@
         ],
         "ext-depends-windows": [
             "xml"
-        ]
+        ],
+        "build-with-php": true
     },
     "snappy": {
         "support": {
@@ -912,7 +919,8 @@
         ]
     },
     "tokenizer": {
-        "type": "builtin"
+        "type": "builtin",
+        "build-with-php": true
     },
     "uuid": {
         "support": {
@@ -995,7 +1003,8 @@
         ],
         "ext-depends-windows": [
             "iconv"
-        ]
+        ],
+        "build-with-php": true
     },
     "xmlreader": {
         "support": {
@@ -1009,7 +1018,8 @@
         "ext-depends-windows": [
             "xml",
             "dom"
-        ]
+        ],
+        "build-with-php": true
     },
     "xmlwriter": {
         "support": {
@@ -1022,7 +1032,8 @@
         ],
         "ext-depends-windows": [
             "xml"
-        ]
+        ],
+        "build-with-php": true
     },
     "xsl": {
         "support": {
diff --git a/src/SPC/builder/BuilderBase.php b/src/SPC/builder/BuilderBase.php
index 08c580ea..599ccdc6 100644
--- a/src/SPC/builder/BuilderBase.php
+++ b/src/SPC/builder/BuilderBase.php
@@ -262,15 +262,17 @@ abstract class BuilderBase
                 if (!$ext->isBuildShared()) {
                     continue;
                 }
-                if (Config::getExt($ext->getName(), 'type') === 'builtin') {
+                if (Config::getExt($ext->getName(), 'type') === 'builtin' || Config::getExt($ext->getName(), 'build-with-php') === true) {
                     if (file_exists(BUILD_MODULES_PATH . '/' . $ext->getName() . '.so')) {
                         logger()->info('Shared extension [' . $ext->getName() . '] was already built by php-src/configure (' . $ext->getName() . '.so)');
                         continue;
                     }
-                    logger()->warning('Shared extension [' . $ext->getName() . '] was built statically by php-src/configure');
-                    continue;
+                    if (Config::getExt($ext->getName(), 'build-with-php') === true) {
+                        logger()->warning('Shared extension [' . $ext->getName() . '] did not build with php-src/configure (' . $ext->getName() . '.so)');
+                        logger()->warning('Try deleting your build and source folders and running `spc build`` again.');
+                        continue;
+                    }
                 }
-                logger()->info('Building extension [' . $ext->getName() . '] as shared extension (' . $ext->getName() . '.so)');
                 $ext->buildShared();
             }
         } catch (RuntimeException $e) {
@@ -293,7 +295,11 @@ abstract class BuilderBase
         foreach ($this->getExts() as $ext) {
             $arg = $ext->getConfigureArg();
             if ($ext->isBuildShared()) {
-                if (Config::getExt($ext->getName(), 'type') === 'builtin') {
+                if (
+                    (Config::getExt($ext->getName(), 'type') === 'builtin' &&
+                    !file_exists(SOURCE_PATH . '/php-src/ext/' . $ext->getName() . '/config.m4')) ||
+                    Config::getExt($ext->getName(), 'build-with-php') === true
+                ) {
                     $arg = $ext->getConfigureArg(true);
                 } else {
                     continue;