diff --git a/Cargo.lock b/Cargo.lock
index 52b1e19..a39270f 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -194,11 +194,11 @@ checksum = "dbf0c48bc1d91375ae5c3cd81e3722dff1abcf81a30960240640d223f59fe0e5"
 
 [[package]]
 name = "proc-macro2"
-version = "1.0.32"
+version = "1.0.47"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ba508cc11742c0dc5c1659771673afbab7a0efab23aa17e854cbab0837ed0b43"
+checksum = "5ea3d908b0e36316caf9e9e2c4625cdde190a7e6f440d794667ed17a1855e725"
 dependencies = [
- "unicode-xid",
+ "unicode-ident",
 ]
 
 [[package]]
@@ -288,13 +288,13 @@ checksum = "1a55ca5f3b68e41c979bf8c46a6f1da892ca4db8f94023ce0bd32407573b1ac0"
 
 [[package]]
 name = "syn"
-version = "1.0.86"
+version = "1.0.103"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8a65b3f4ffa0092e9887669db0eae07941f023991ab58ea44da8fe8e2d511c6b"
+checksum = "a864042229133ada95abf3b54fdc62ef5ccabe9515b64717bcb9a1919e59445d"
 dependencies = [
  "proc-macro2",
  "quote",
- "unicode-xid",
+ "unicode-ident",
 ]
 
 [[package]]
@@ -329,10 +329,10 @@ dependencies = [
 ]
 
 [[package]]
-name = "unicode-xid"
-version = "0.2.1"
+name = "unicode-ident"
+version = "1.0.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f7fe0bb3479651439c9112f72b6c505038574c9fbb575ed1bf3b797fa39dd564"
+checksum = "6ceab39d59e4c9499d4e5a8ee0e2735b891bb7308ac83dfb4e80cad195c9f6f3"
 
 [[package]]
 name = "unindent"
diff --git a/Cargo.toml b/Cargo.toml
index b27a3d7..b81e716 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -13,5 +13,5 @@ crate-type = ["cdylib", "rlib"]
 [dependencies]
 quote = "1.0.10"
 zip = "0.5.13"
-syn = { version = "1.0.86", features = ["full"] }
+syn = { version = "1.0.103", features = ["full"] }
 pyo3 = { version = "0.15.1", features = ["extension-module"] }  # version corresponds to numpy