diff --git a/CONTRIBUTORS.md b/CONTRIBUTORS.md
index c34eb45..ec0042d 100644
--- a/CONTRIBUTORS.md
+++ b/CONTRIBUTORS.md
@@ -3,3 +3,4 @@
 | GitHub user | Real Name | Affiliation | Date |
 | ----------- | --------- | ----------- | ---- |
 | james-bruten-mo | James Bruten | Met Office | 2025-12-09 |
+| trjr | Todd Jones | University of Reading | 2026-05-01 |
diff --git a/checkpoint_files/.gitignore b/checkpoint_files/.gitignore
new file mode 100644
index 0000000..5e7d273
--- /dev/null
+++ b/checkpoint_files/.gitignore
@@ -0,0 +1,4 @@
+# Ignore everything in this directory
+*
+# Except this file
+!.gitignore
diff --git a/diagnostic_files/.gitignore b/diagnostic_files/.gitignore
new file mode 100644
index 0000000..5e7d273
--- /dev/null
+++ b/diagnostic_files/.gitignore
@@ -0,0 +1,4 @@
+# Ignore everything in this directory
+*
+# Except this file
+!.gitignore
diff --git a/ib_diagnostic_files/.gitignore b/ib_diagnostic_files/.gitignore
new file mode 100644
index 0000000..5e7d273
--- /dev/null
+++ b/ib_diagnostic_files/.gitignore
@@ -0,0 +1,4 @@
+# Ignore everything in this directory
+*
+# Except this file
+!.gitignore
diff --git a/monc_stdout/.gitignore b/monc_stdout/.gitignore
new file mode 100644
index 0000000..5e7d273
--- /dev/null
+++ b/monc_stdout/.gitignore
@@ -0,0 +1,4 @@
+# Ignore everything in this directory
+*
+# Except this file
+!.gitignore