diff --git a/cpp/ql/lib/semmle/code/cpp/dataflow/internal/ExternalFlowExtensions.qll b/cpp/ql/lib/semmle/code/cpp/dataflow/internal/ExternalFlowExtensions.qll
index cd1af34c8d8..16597020620 100644
--- a/cpp/ql/lib/semmle/code/cpp/dataflow/internal/ExternalFlowExtensions.qll
+++ b/cpp/ql/lib/semmle/code/cpp/dataflow/internal/ExternalFlowExtensions.qll
@@ -2,6 +2,8 @@
  * This module provides extensible predicates for defining MaD models.
  */
 
+private import codeql.mad.static.MaD as SharedMaD
+
 /**
  * Holds if an external source model exists for the given parameters.
  */
@@ -18,6 +20,22 @@ extensible predicate sinkModel(
   string input, string kind, string provenance, QlBuiltins::ExtensionId madId
 );
 
+/**
+ * Holds if a barrier model exists for the given parameters.
+ */
+extensible predicate barrierModel(
+  string namespace, string type, boolean subtypes, string name, string signature, string ext,
+  string output, string kind, string provenance, QlBuiltins::ExtensionId madId
+);
+
+/**
+ * Holds if a barrier guard model exists for the given parameters.
+ */
+extensible predicate barrierGuardModel(
+  string namespace, string type, boolean subtypes, string name, string signature, string ext,
+  string input, string acceptingvalue, string kind, string provenance, QlBuiltins::ExtensionId madId
+);
+
 /**
  * Holds if an external summary model exists for the given parameters.
  */
@@ -25,3 +43,14 @@ extensible predicate summaryModel(
   string namespace, string type, boolean subtypes, string name, string signature, string ext,
   string input, string output, string kind, string provenance, QlBuiltins::ExtensionId madId
 );
+
+/**
+ * Holds if a neutral model exists for the given parameters.
+ */
+extensible predicate neutralModel(
+  string namespace, string type, string name, string signature, string kind, string provenance
+);
+
+module Extensions implements SharedMaD::ExtensionsSig {
+  import ExternalFlowExtensions
+}
diff --git a/csharp/ql/lib/semmle/code/csharp/dataflow/internal/ExternalFlowExtensions.qll b/csharp/ql/lib/semmle/code/csharp/dataflow/internal/ExternalFlowExtensions.qll
index f761a0a9f5c..f845ddf7951 100644
--- a/csharp/ql/lib/semmle/code/csharp/dataflow/internal/ExternalFlowExtensions.qll
+++ b/csharp/ql/lib/semmle/code/csharp/dataflow/internal/ExternalFlowExtensions.qll
@@ -2,6 +2,8 @@
  * This module provides extensible predicates for defining MaD models.
  */
 
+private import codeql.mad.static.MaD as SharedMaD
+
 /**
  * Holds if a source model exists for the given parameters.
  */
@@ -18,6 +20,22 @@ extensible predicate sinkModel(
   string input, string kind, string provenance, QlBuiltins::ExtensionId madId
 );
 
+/**
+ * Holds if a barrier model exists for the given parameters.
+ */
+extensible predicate barrierModel(
+  string namespace, string type, boolean subtypes, string name, string signature, string ext,
+  string output, string kind, string provenance, QlBuiltins::ExtensionId madId
+);
+
+/**
+ * Holds if a barrier guard model exists for the given parameters.
+ */
+extensible predicate barrierGuardModel(
+  string namespace, string type, boolean subtypes, string name, string signature, string ext,
+  string input, string acceptingvalue, string kind, string provenance, QlBuiltins::ExtensionId madId
+);
+
 /**
  * Holds if a summary model exists for the given parameters.
  */
@@ -32,3 +50,7 @@ extensible predicate summaryModel(
 extensible predicate neutralModel(
   string namespace, string type, string name, string signature, string kind, string provenance
 );
+
+module Extensions implements SharedMaD::ExtensionsSig {
+  import ExternalFlowExtensions
+}
diff --git a/go/ql/lib/semmle/go/dataflow/internal/ExternalFlowExtensions.qll b/go/ql/lib/semmle/go/dataflow/internal/ExternalFlowExtensions.qll
index b1e1c906028..588951944e1 100644
--- a/go/ql/lib/semmle/go/dataflow/internal/ExternalFlowExtensions.qll
+++ b/go/ql/lib/semmle/go/dataflow/internal/ExternalFlowExtensions.qll
@@ -2,6 +2,8 @@
  * This module provides extensible predicates for defining MaD models.
  */
 
+private import codeql.mad.static.MaD as SharedMaD
+
 /**
  * Holds if a source model exists for the given parameters.
  */
@@ -18,6 +20,22 @@ extensible predicate sinkModel(
   string input, string kind, string provenance, QlBuiltins::ExtensionId madId
 );
 
+/**
+ * Holds if a barrier model exists for the given parameters.
+ */
+extensible predicate barrierModel(
+  string package, string type, boolean subtypes, string name, string signature, string ext,
+  string output, string kind, string provenance, QlBuiltins::ExtensionId madId
+);
+
+/**
+ * Holds if a barrier guard model exists for the given parameters.
+ */
+extensible predicate barrierGuardModel(
+  string package, string type, boolean subtypes, string name, string signature, string ext,
+  string input, string acceptingvalue, string kind, string provenance, QlBuiltins::ExtensionId madId
+);
+
 /**
  * Holds if a summary model exists for the given parameters.
  */
@@ -37,3 +55,7 @@ extensible predicate neutralModel(
  * Holds if the package `package` is part of the group `group`.
  */
 extensible predicate packageGrouping(string group, string package);
+
+module Extensions implements SharedMaD::ExtensionsSig {
+  import ExternalFlowExtensions
+}