diff --git a/courses/dss/Cargo.lock b/courses/dss/Cargo.lock
index 18466a33..63b5b1cc 100644
--- a/courses/dss/Cargo.lock
+++ b/courses/dss/Cargo.lock
@@ -513,6 +513,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "once_cell"
+version = "1.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7709cef83f0c1f58f666e746a08b21e0085f7440fa6a29cc194d68aac97a4225"
+
 [[package]]
 name = "oorandom"
 version = "11.1.0"
@@ -905,11 +911,11 @@ dependencies = [
 
 [[package]]
 name = "thread_local"
-version = "1.0.1"
+version = "1.1.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d40c6d1b69745a6ec6fb1ca717914848da4b44ae29d9b3080cbee91d72a69b14"
+checksum = "5516c27b78311c50bf42c071425c560ac799b11c30b31f87e3081965fe5e0180"
 dependencies = [
- "lazy_static",
+ "once_cell",
 ]
 
 [[package]]