diff --git a/.github/workflows/pipeline.yml b/.github/workflows/pipeline.yml
index d6f5e92d..1500a938 100644
--- a/.github/workflows/pipeline.yml
+++ b/.github/workflows/pipeline.yml
@@ -176,7 +176,7 @@ jobs:
           papermill notebooks/1-single-node.ipynb notebooks/1-single-node-out.ipynb -k python3
           flux start papermill notebooks/2-hpc-cluster.ipynb notebooks/2-hpc-cluster-out.ipynb -k python3
           flux start papermill notebooks/3-hpc-job.ipynb notebooks/3-hpc-job-out.ipynb -k python3
-          papermill notebooks/4-developer.ipynb notebooks/4-developer-out.ipynb -k python3
+          papermill notebooks/5-developer.ipynb notebooks/5-developer-out.ipynb -k python3
 
   notebooks_integration:
     needs: [black]
@@ -198,8 +198,8 @@ jobs:
         shell: bash -l {0}
         timeout-minutes: 20
         run: |
-          flux start papermill notebooks/5-1-gpaw.ipynb notebooks/5-1-gpaw-out.ipynb -k python3
-          flux start papermill notebooks/5-2-quantum-espresso.ipynb notebooks/5-2-quantum-espresso-out.ipynb -k python3
+          flux start papermill notebooks/4-1-gpaw.ipynb notebooks/4-1-gpaw-out.ipynb -k python3
+          flux start papermill notebooks/4-2-quantum-espresso.ipynb notebooks/4-2-quantum-espresso-out.ipynb -k python3
 
   unittest_flux_mpich:
     needs: [black]
diff --git a/README.md b/README.md
index e7756136..8c3c93e9 100644
--- a/README.md
+++ b/README.md
@@ -144,8 +144,8 @@ as hierarchical job scheduler within the allocations.
   * [SLURM with Flux](https://executorlib.readthedocs.io/en/latest/3-hpc-job.html#slurm-with-flux)
   * [Flux](https://executorlib.readthedocs.io/en/latest/3-hpc-job.html#flux)
 * [Application](https://executorlib.readthedocs.io/en/latest/application.html)
-  * [GPAW](https://executorlib.readthedocs.io/en/latest/5-1-gpaw.html)
-  * [Quantum Espresso](https://executorlib.readthedocs.io/en/latest/5-2-quantum-espresso.html)
+  * [GPAW](https://executorlib.readthedocs.io/en/latest/4-1-gpaw.html)
+  * [Quantum Espresso](https://executorlib.readthedocs.io/en/latest/4-2-quantum-espresso.html)
 * [Trouble Shooting](https://executorlib.readthedocs.io/en/latest/trouble_shooting.html)
   * [Filesystem Usage](https://executorlib.readthedocs.io/en/latest/trouble_shooting.html#filesystem-usage)
   * [Firewall Issues](https://executorlib.readthedocs.io/en/latest/trouble_shooting.html#firewall-issues)
@@ -154,14 +154,14 @@ as hierarchical job scheduler within the allocations.
   * [Python Version](https://executorlib.readthedocs.io/en/latest/trouble_shooting.html#python-version)
   * [Resource Dictionary](https://executorlib.readthedocs.io/en/latest/trouble_shooting.html#resource-dictionary)
   * [SSH Connection](https://executorlib.readthedocs.io/en/latest/trouble_shooting.html#ssh-connection)
-* [Support & Contribution](https://executorlib.readthedocs.io/en/latest/4-developer.html)
-  * [Issues](https://executorlib.readthedocs.io/en/latest/4-developer.html#issues)
-  * [Pull Requests](https://executorlib.readthedocs.io/en/latest/4-developer.html#pull-requests)
-  * [License](https://executorlib.readthedocs.io/en/latest/4-developer.html#license)
-  * [Modules](https://executorlib.readthedocs.io/en/latest/4-developer.html#modules)
-  * [Interface Class Hierarchy](https://executorlib.readthedocs.io/en/latest/4-developer.html#interface-class-hierarchy)
-  * [Test Environment](https://executorlib.readthedocs.io/en/latest/4-developer.html#test-environment)
-  * [Communication](https://executorlib.readthedocs.io/en/latest/4-developer.html#communication)
-  * [External Libraries](https://executorlib.readthedocs.io/en/latest/4-developer.html#external-libraries)
-  * [External Executables](https://executorlib.readthedocs.io/en/latest/4-developer.html#external-executables)
+* [Support & Contribution](https://executorlib.readthedocs.io/en/latest/5-developer.html)
+  * [Issues](https://executorlib.readthedocs.io/en/latest/5-developer.html#issues)
+  * [Pull Requests](https://executorlib.readthedocs.io/en/latest/5-developer.html#pull-requests)
+  * [License](https://executorlib.readthedocs.io/en/latest/5-developer.html#license)
+  * [Modules](https://executorlib.readthedocs.io/en/latest/5-developer.html#modules)
+  * [Interface Class Hierarchy](https://executorlib.readthedocs.io/en/latest/5-developer.html#interface-class-hierarchy)
+  * [Test Environment](https://executorlib.readthedocs.io/en/latest/5-developer.html#test-environment)
+  * [Communication](https://executorlib.readthedocs.io/en/latest/5-developer.html#communication)
+  * [External Libraries](https://executorlib.readthedocs.io/en/latest/5-developer.html#external-libraries)
+  * [External Executables](https://executorlib.readthedocs.io/en/latest/5-developer.html#external-executables)
 * [Interface](https://executorlib.readthedocs.io/en/latest/api.html)
diff --git a/docs/_toc.yml b/docs/_toc.yml
index 5abb79fb..ca7887a9 100644
--- a/docs/_toc.yml
+++ b/docs/_toc.yml
@@ -7,8 +7,8 @@ chapters:
 - file: 3-hpc-job.ipynb
 - file: application.md
   sections:
-    - file: 5-1-gpaw.ipynb
-    - file: 5-2-quantum-espresso.ipynb
+    - file: 4-1-gpaw.ipynb
+    - file: 4-2-quantum-espresso.ipynb
 - file: trouble_shooting.md
-- file: 4-developer.ipynb
+- file: 5-developer.ipynb
 - file: api.rst
diff --git a/notebooks/5-1-gpaw.ipynb b/notebooks/4-1-gpaw.ipynb
similarity index 100%
rename from notebooks/5-1-gpaw.ipynb
rename to notebooks/4-1-gpaw.ipynb
diff --git a/notebooks/5-2-quantum-espresso.ipynb b/notebooks/4-2-quantum-espresso.ipynb
similarity index 100%
rename from notebooks/5-2-quantum-espresso.ipynb
rename to notebooks/4-2-quantum-espresso.ipynb
diff --git a/notebooks/4-developer.ipynb b/notebooks/5-developer.ipynb
similarity index 100%
rename from notebooks/4-developer.ipynb
rename to notebooks/5-developer.ipynb