diff --git a/third-party/manyhow/Cargo.toml b/third-party/manyhow/Cargo.toml
index 5909456..dd62aca 100644
--- a/third-party/manyhow/Cargo.toml
+++ b/third-party/manyhow/Cargo.toml
@@ -84,7 +84,7 @@ default-features = false
 package = "syn"
 
 [dependencies.syn2]
-version = "2"
+version = "3"
 features = [
     "printing",
     "parsing",
@@ -101,7 +101,7 @@ version = "1"
 features = ["span-locations"]
 
 [dev-dependencies.syn2]
-version = "2"
+version = "3"
 features = ["full"]
 package = "syn"