diff --git a/templates/go/msg.go b/templates/go/msg.go
index dc40c2ebc..bc01ace08 100644
--- a/templates/go/msg.go
+++ b/templates/go/msg.go
@@ -91,5 +91,23 @@ var _ error = {{ errname . }}{}
 		var {{ lookup .Field "Pattern" }} = regexp.MustCompile({{ lit .Rules.GetPattern }})
 	{{ end }}{{ end }}
 
+	{{ if has .Rules "Items"}}{{ if .Rules.Items }}
+	{{ if has .Rules.Items.GetString_ "Pattern" }} {{ if .Rules.Items.GetString_.Pattern }}
+		var {{ lookup .Field "Pattern" }} = regexp.MustCompile({{ lit .Rules.Items.GetString_.GetPattern }})
+	{{ end }}{{ end }}
+	{{ end }}{{ end }}
+
+	{{ if has .Rules "Keys"}}{{ if .Rules.Keys }}
+	{{ if has .Rules.Keys.GetString_ "Pattern" }} {{ if .Rules.Keys.GetString_.Pattern }}
+		var {{ lookup .Field "Pattern" }} = regexp.MustCompile({{ lit .Rules.Keys.GetString_.GetPattern }})
+	{{ end }}{{ end }}
+	{{ end }}{{ end }}
+
+	{{ if has .Rules "Values"}}{{ if .Rules.Values }}
+	{{ if has .Rules.Values.GetString_ "Pattern" }} {{ if .Rules.Values.GetString_.Pattern }}
+		var {{ lookup .Field "Pattern" }} = regexp.MustCompile({{ lit .Rules.Values.GetString_.GetPattern }})
+	{{ end }}{{ end }}
+	{{ end }}{{ end }}
+
 {{ end }}{{ end }}
 `
diff --git a/tests/harness/cases/maps.proto b/tests/harness/cases/maps.proto
index 2bc7b2d56..8b76894fe 100644
--- a/tests/harness/cases/maps.proto
+++ b/tests/harness/cases/maps.proto
@@ -19,3 +19,6 @@ message MapNoSparse {
 
 message MapKeys   { map<sint32, string> val = 1 [(validate.rules).map.keys.sint32.lt = 0]; }
 message MapValues { map<string, string> val = 1 [(validate.rules).map.values.string.min_len = 3]; }
+
+message MapKeysPattern   { map<string, string> val = 1 [(validate.rules).map.keys.string.pattern = "(?i)^[a-z0-9]+$"]; }
+message MapValuesPattern { map<string, string> val = 1 [(validate.rules).map.values.string.pattern = "(?i)^[a-z0-9]+$"]; }
diff --git a/tests/harness/cases/repeated.proto b/tests/harness/cases/repeated.proto
index e44178963..c80f6ff61 100644
--- a/tests/harness/cases/repeated.proto
+++ b/tests/harness/cases/repeated.proto
@@ -18,4 +18,5 @@ message RepeatedMinMax    { repeated sfixed32 val = 1 [(validate.rules).repeated
 message RepeatedExact     { repeated uint32 val = 1 [(validate.rules).repeated = {min_items: 3, max_items: 3}]; }
 message RepeatedUnique    { repeated string val = 1 [(validate.rules).repeated.unique = true]; }
 message RepeatedItemRule  { repeated float val = 1 [(validate.rules).repeated.items.float.gt = 0]; }
+message RepeatedItemPattern  { repeated string val = 1 [(validate.rules).repeated.items.string.pattern = "(?i)^[a-z0-9]+$"]; }
 message RepeatedEmbedSkip { repeated Embed val = 1 [(validate.rules).repeated.items.message.skip = true]; }
diff --git a/tests/harness/executor/cases.go b/tests/harness/executor/cases.go
index fe945107f..612265a48 100644
--- a/tests/harness/executor/cases.go
+++ b/tests/harness/executor/cases.go
@@ -950,7 +950,9 @@ var repeatedCases = []TestCase{
 
 	{"repeated - items - valid", &cases.RepeatedItemRule{Val: []float32{1, 2, 3}}, true},
 	{"repeated - items - valid (empty)", &cases.RepeatedItemRule{Val: []float32{}}, true},
+	{"repeated - items - valid (pattern)", &cases.RepeatedItemPattern{Val: []string{"Alpha", "Beta123"}}, true},
 	{"repeated - items - invalid", &cases.RepeatedItemRule{Val: []float32{1, -2, 3}}, false},
+	{"repeated - items - invalid (pattern)", &cases.RepeatedItemPattern{Val: []string{"Alpha", "!@#$%^&*()"}}, false},
 
 	{"repeated - embed skip - valid", &cases.RepeatedEmbedSkip{Val: []*cases.Embed{{Val: 1}}}, true},
 	{"repeated - embed skip - valid (invalid element)", &cases.RepeatedEmbedSkip{Val: []*cases.Embed{{Val: -1}}}, true},
@@ -983,11 +985,15 @@ var mapCases = []TestCase{
 
 	{"map - keys - valid", &cases.MapKeys{Val: map[int32]string{-1: "a", -2: "b"}}, true},
 	{"map - keys - valid (empty)", &cases.MapKeys{Val: map[int32]string{}}, true},
+	{"map - keys - valid (pattern)", &cases.MapKeysPattern{Val: map[string]string{"A": "a"}}, true},
 	{"map - keys - invalid", &cases.MapKeys{Val: map[int32]string{1: "a"}}, false},
+	{"map - keys - invalid (pattern)", &cases.MapKeysPattern{Val: map[string]string{"A": "a", "!@#$%^&*()": "b"}}, false},
 
 	{"map - values - valid", &cases.MapValues{Val: map[string]string{"a": "Alpha", "b": "Beta"}}, true},
 	{"map - values - valid (empty)", &cases.MapValues{Val: map[string]string{}}, true},
+	{"map - values - valid (pattern)", &cases.MapValuesPattern{Val: map[string]string{"a": "A"}}, true},
 	{"map - values - invalid", &cases.MapValues{Val: map[string]string{"a": "A", "b": "B"}}, false},
+	{"map - values - invalid (pattern)", &cases.MapValuesPattern{Val: map[string]string{"a": "A", "b": "!@#$%^&*()"}}, false},
 }
 
 var oneofCases = []TestCase{