diff --git a/pkgs/by-name/pr/prometheus/package.nix b/pkgs/by-name/pr/prometheus/package.nix
index fae4e2500a89..40cfe2fec8f0 100644
--- a/pkgs/by-name/pr/prometheus/package.nix
+++ b/pkgs/by-name/pr/prometheus/package.nix
@@ -63,6 +63,8 @@ let
 
     env.CI = true;
 
+    __darwinAllowLocalNetworking = true;
+
     doCheck = true;
     checkPhase = ''
       runHook preCheck
@@ -92,6 +94,10 @@ buildGoModule (finalAttrs: {
 
   proxyVendor = true;
 
+  patches = [
+    ./prometheus-pr18519-fix-TestFsType.patch
+  ];
+
   outputs = [
     "out"
     "doc"
diff --git a/pkgs/by-name/pr/prometheus/prometheus-pr18519-fix-TestFsType.patch b/pkgs/by-name/pr/prometheus/prometheus-pr18519-fix-TestFsType.patch
new file mode 100644
index 000000000000..a7ad2c20b32c
--- /dev/null
+++ b/pkgs/by-name/pr/prometheus/prometheus-pr18519-fix-TestFsType.patch
@@ -0,0 +1,25 @@
+--- a/util/runtime/statfs_unix_test.go
++++ b/util/runtime/statfs_unix_test.go
+@@ -19,20 +19,18 @@ import (
+ 	"os"
+ 	"testing"
+
+-	"github.com/grafana/regexp"
+ 	"github.com/stretchr/testify/require"
+ )
+
+-var regexpFsType = regexp.MustCompile("^[A-Z][A-Z0-9_]*_MAGIC$")
+-
+ func TestFsType(t *testing.T) {
+ 	var fsType string
+
+ 	path, err := os.Getwd()
+ 	require.NoError(t, err)
+
++	// A real path must yield a non-zero filesystem type.
+ 	fsType = FsType(path)
+-	require.Regexp(t, regexpFsType, fsType)
++	require.NotEqual(t, "0", fsType)
+
+ 	fsType = FsType("/no/where/to/be/found")
+ 	require.Equal(t, "0", fsType)