diff --git a/Cargo.toml b/Cargo.toml
index 9b19c02..60f1b5d 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -24,6 +24,7 @@ num = { version = "0.4", optional = true }
 paste = "1"
 serde = { version = "1", optional = true }
 serde_json = { version = "1", optional = true }
+thiserror = "1.0"
 wasm-bindgen = "0.2"
 wasm-bindgen-futures = "0.4"