diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index b30eeffc..a26d7dd2 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -23,7 +23,7 @@ jobs:
           python-version: "3.12"
       - uses: julia-actions/setup-julia@v1
         with:
-          version: '1.10.1'
+          version: '1.9.2'
       - uses: julia-actions/cache@v1
       - name: Install JuliaFormatter and format
         run: |
diff --git a/.github/workflows/docs.yml b/.github/workflows/docs.yml
index 6deb6c2d..7793b3c3 100644
--- a/.github/workflows/docs.yml
+++ b/.github/workflows/docs.yml
@@ -48,7 +48,7 @@ jobs:
       
       - uses: julia-actions/setup-julia@v1
         with:
-          version: '1.10.1'
+          version: '1.9.3'
       - uses: julia-actions/cache@v1
         with:
           cache-name: ${{ runner.os }}-${{ steps.get-date.outputs.date }}
diff --git a/docs/julia/heater_3d.jl b/docs/julia/heater_3d.jl
index 0010a40a..b51087ba 100644
--- a/docs/julia/heater_3d.jl
+++ b/docs/julia/heater_3d.jl
@@ -11,7 +11,7 @@
 #   kernelspec:
 #     display_name: base
 #     language: julia
-#     name: julia-1.10
+#     name: julia-1.9
 # ---
 
 # %% [markdown]
diff --git a/docs/julia/lithium_niobate_phase_shifter.jl b/docs/julia/lithium_niobate_phase_shifter.jl
index 366b7ff0..c78ecd43 100644
--- a/docs/julia/lithium_niobate_phase_shifter.jl
+++ b/docs/julia/lithium_niobate_phase_shifter.jl
@@ -11,7 +11,7 @@
 #   kernelspec:
 #     display_name: base
 #     language: julia
-#     name: julia-1.10
+#     name: julia-1.9
 # ---
 
 # %% [markdown]
diff --git a/docs/julia/microstrip.jl b/docs/julia/microstrip.jl
index 4d534aac..27ffe145 100644
--- a/docs/julia/microstrip.jl
+++ b/docs/julia/microstrip.jl
@@ -11,7 +11,7 @@
 #   kernelspec:
 #     display_name: base
 #     language: julia
-#     name: julia-1.10
+#     name: julia-1.9
 # ---
 
 # %% [markdown]
diff --git a/docs/julia/thermal_fill.jl b/docs/julia/thermal_fill.jl
index 581c36bd..af329b21 100644
--- a/docs/julia/thermal_fill.jl
+++ b/docs/julia/thermal_fill.jl
@@ -11,7 +11,7 @@
 #   kernelspec:
 #     display_name: base
 #     language: julia
-#     name: julia-1.10
+#     name: julia-1.9
 # ---
 
 # %% [markdown]
diff --git a/docs/julia/thermal_simple.jl b/docs/julia/thermal_simple.jl
index 83389206..f03a7302 100644
--- a/docs/julia/thermal_simple.jl
+++ b/docs/julia/thermal_simple.jl
@@ -11,7 +11,7 @@
 #   kernelspec:
 #     display_name: base
 #     language: julia
-#     name: julia-1.10
+#     name: julia-1.9
 # ---
 
 # %% [markdown]
diff --git a/docs/julia/waveguide.jl b/docs/julia/waveguide.jl
index 2f7684d8..9e80f3ce 100644
--- a/docs/julia/waveguide.jl
+++ b/docs/julia/waveguide.jl
@@ -11,7 +11,7 @@
 #   kernelspec:
 #     display_name: base
 #     language: julia
-#     name: julia-1.10
+#     name: julia-1.9
 # ---
 
 # %% [markdown]
diff --git a/docs/julia/waveguide_anisotropic.jl b/docs/julia/waveguide_anisotropic.jl
index 39596207..4bf62e8b 100644
--- a/docs/julia/waveguide_anisotropic.jl
+++ b/docs/julia/waveguide_anisotropic.jl
@@ -11,7 +11,7 @@
 #   kernelspec:
 #     display_name: base
 #     language: julia
-#     name: julia-1.10
+#     name: julia-1.9
 # ---
 
 # %% [markdown]
diff --git a/docs/julia/waveguide_bent.jl b/docs/julia/waveguide_bent.jl
index beb82e09..f171918a 100644
--- a/docs/julia/waveguide_bent.jl
+++ b/docs/julia/waveguide_bent.jl
@@ -11,7 +11,7 @@
 #   kernelspec:
 #     display_name: base
 #     language: julia
-#     name: julia-1.10
+#     name: julia-1.9
 # ---
 
 # %% [markdown]
diff --git a/docs/julia/waveguide_bent_coupling.jl b/docs/julia/waveguide_bent_coupling.jl
index 9a3e22f6..a0271536 100644
--- a/docs/julia/waveguide_bent_coupling.jl
+++ b/docs/julia/waveguide_bent_coupling.jl
@@ -11,7 +11,7 @@
 #   kernelspec:
 #     display_name: base
 #     language: julia
-#     name: julia-1.10
+#     name: julia-1.9
 # ---
 
 # %% [markdown]
diff --git a/docs/julia/waveguide_overlap_integral.jl b/docs/julia/waveguide_overlap_integral.jl
index ed8c5b21..6600d927 100644
--- a/docs/julia/waveguide_overlap_integral.jl
+++ b/docs/julia/waveguide_overlap_integral.jl
@@ -11,7 +11,7 @@
 #   kernelspec:
 #     display_name: base
 #     language: julia
-#     name: julia-1.10
+#     name: julia-1.9
 # ---
 
 # %% [markdown]