diff --git a/.github/workflows/CI.yml b/.github/workflows/CI.yml
index 730df49..8861727 100644
--- a/.github/workflows/CI.yml
+++ b/.github/workflows/CI.yml
@@ -15,7 +15,7 @@ jobs:
       fail-fast: false
       matrix:
         version:
-          - '1.6'
+          - '1.9'
           - 'nightly'
         os:
           - ubuntu-latest
diff --git a/Project.toml b/Project.toml
index 00c5a65..8eb12d5 100644
--- a/Project.toml
+++ b/Project.toml
@@ -19,7 +19,7 @@ Polyhedra = "0.6, 0.7"
 ProgressMeter = "1"
 RecipesBase = "1"
 StaticArrays = "0.12, 1"
-julia = "1.6, 1.7"
+julia = "1.9"
 
 [extras]
 Test = "8dfed614-e22c-5e08-85e1-65c5234f0b40"
diff --git a/src/raycast.jl b/src/raycast.jl
index e865a0b..73deaad 100644
--- a/src/raycast.jl
+++ b/src/raycast.jl
@@ -116,6 +116,7 @@ function raycast(sig::Sigma, r::Point, u::Point, xs::Points, searcher::RaycastIn
     return tau, t
 end
 
+global warn_degenerate::Bool = false
 
 struct RaycastIncircleSkip{T}
     tree::T
@@ -162,9 +163,11 @@ function raycast(sig::Sigma, r::Point, u::Point, xs::Points, searcher::RaycastIn
 
         (j in sig || j == i) && break  # converged to the smallest circle
 
-        # why is this test actually meaningful?
-        dold = sqrt(sum(abs2, x0-candidate))
-        isapprox(d, dold) && @warn "degenerate vertex at $sig + [$j]/[$i] ($d $dold)"
+        if warn_degenerate
+            # why is this test actually meaningful?
+            dold = sqrt(sum(abs2, x0 - candidate))
+            isapprox(d, dold) && @warn "degenerate vertex at $sig + [$j]/[$i] ($d $dold)"
+        end
 
         i = j
     end