diff --git a/cpp/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md b/cpp/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
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+++ b/cpp/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
@@ -0,0 +1,4 @@
+---
+category: feature
+---
+* Data flow barriers and barrier guards can now be added using data extensions. For more information see `Customizing library models for C and C++ <https://codeql.github.com/docs/codeql-language-guides/customizing-library-models-for-cpp/>`__.
diff --git a/csharp/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md b/csharp/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
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index 00000000000..4d5cc0c0d0d
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+++ b/csharp/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
@@ -0,0 +1,4 @@
+---
+category: feature
+---
+* Data flow barriers and barrier guards can now be added using data extensions. For more information see `Customizing library models for C# <https://codeql.github.com/docs/codeql-language-guides/customizing-library-models-for-csharp/>`__.
diff --git a/go/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md b/go/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
new file mode 100644
index 00000000000..1e86b59d5b5
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+++ b/go/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
@@ -0,0 +1,4 @@
+---
+category: feature
+---
+* Data flow barriers and barrier guards can now be added using data extensions. For more information see `Customizing library models for Go <https://codeql.github.com/docs/codeql-language-guides/customizing-library-models-for-go/>`__.
diff --git a/java/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md b/java/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
new file mode 100644
index 00000000000..d4ae1f8711d
--- /dev/null
+++ b/java/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
@@ -0,0 +1,4 @@
+---
+category: feature
+---
+* Data flow barriers and barrier guards can now be added using data extensions. For more information see `Customizing library models for Java and Kotlin <https://codeql.github.com/docs/codeql-language-guides/customizing-library-models-for-java-and-kotlin/>`__.
diff --git a/javascript/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md b/javascript/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
new file mode 100644
index 00000000000..e8bacba89b1
--- /dev/null
+++ b/javascript/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
@@ -0,0 +1,4 @@
+---
+category: feature
+---
+* Data flow barriers and barrier guards can now be added using data extensions. For more information see `Customizing library models for JavaScript <https://codeql.github.com/docs/codeql-language-guides/customizing-library-models-for-javascript/>`__.
diff --git a/python/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md b/python/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
new file mode 100644
index 00000000000..b33a89ba776
--- /dev/null
+++ b/python/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
@@ -0,0 +1,4 @@
+---
+category: feature
+---
+* Data flow barriers and barrier guards can now be added using data extensions. For more information see `Customizing library models for Python <https://codeql.github.com/docs/codeql-language-guides/customizing-library-models-for-python/>`__.
diff --git a/ruby/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md b/ruby/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
new file mode 100644
index 00000000000..fecf79a0de7
--- /dev/null
+++ b/ruby/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
@@ -0,0 +1,4 @@
+---
+category: feature
+---
+* Data flow barriers and barrier guards can now be added using data extensions. For more information see `Customizing library models for Ruby <https://codeql.github.com/docs/codeql-language-guides/customizing-library-models-for-ruby/>`__.
diff --git a/rust/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md b/rust/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
new file mode 100644
index 00000000000..5e97a1533a9
--- /dev/null
+++ b/rust/ql/lib/change-notes/2026-03-20-data-extensions-barriers.md
@@ -0,0 +1,4 @@
+---
+category: feature
+---
+* Data flow barriers and barrier guards can now be added using data extensions.