diff --git a/material/5_fri/optimizing_julia/optimizing_julia.jl b/material/5_fri/optimizing_julia/optimizing_julia.jl
index 2475b70..929351a 100644
--- a/material/5_fri/optimizing_julia/optimizing_julia.jl
+++ b/material/5_fri/optimizing_julia/optimizing_julia.jl
@@ -118,6 +118,9 @@ using BenchmarkTools
 @profview simulate()
 
 # Task: Optimize the code!
+#
+# You can find one improved version in the file
+# [`optimizing_julia_solution.jl`](optimizing_julia_solution.jl).
 
 
 # ## Introduction to generic Julia code and AD
diff --git a/material/5_fri/optimizing_julia/optimizing_julia.md b/material/5_fri/optimizing_julia/optimizing_julia.md
index 7b1296c..f62df7e 100644
--- a/material/5_fri/optimizing_julia/optimizing_julia.md
+++ b/material/5_fri/optimizing_julia/optimizing_julia.md
@@ -134,6 +134,9 @@ PProf.jl (`pprof()` after creating a profile via `@profview`).
 
 Task: Optimize the code!
 
+You can find one improved version in the file
+[`optimizing_julia_solution.jl`](optimizing_julia_solution.jl).
+
 ## Introduction to generic Julia code and AD
 
 One of the strengths of Julia is that you can use quite a few