diff --git a/Cargo.lock b/Cargo.lock
index 8980e2a5d..69cf89df3 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -341,7 +341,7 @@ checksum = "0e97ce7de6cf12de5d7226c73f5ba9811622f4db3a5b91b55c53e987e5f91cba"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -433,7 +433,7 @@ checksum = "b9ccdd8f2a161be9bd5c023df56f1b2a0bd1d83872ae53b71a84a12c9bf6e842"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -562,7 +562,7 @@ dependencies = [
  "regex",
  "rustc-hash",
  "shlex",
- "syn 2.0.20",
+ "syn 2.0.23",
  "which",
 ]
 
@@ -1401,7 +1401,7 @@ checksum = "487585f4d0c6655fe74905e2504d8ad6908e4db67f744eb140876906c2f3175d"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -1454,7 +1454,7 @@ checksum = "5e9a1f9f7d83e59740248a6e14ecf93929ade55027844dfcea78beafccc15745"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -1721,7 +1721,7 @@ checksum = "89ca545a94061b6365f2c7355b4b32bd20df3ff95f02da9329b34ccc3bd6ee72"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -2700,7 +2700,7 @@ version = "0.1.0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -3355,7 +3355,7 @@ checksum = "a948666b637a0f465e8564c73e89d4dde00d72d4d473cc972f390fc3dcee7d9c"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -3591,7 +3591,7 @@ checksum = "39407670928234ebc5e6e580247dd567ad73a3578460c5990f9503df207e8f07"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -3707,7 +3707,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3b69d39aab54d069e7f2fe8cb970493e7834601ca2d8c65fd7bbd183578080d1"
 dependencies = [
  "proc-macro2",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -4335,7 +4335,7 @@ checksum = "d9735b638ccc51c28bf6914d90a2e9725b377144fc612c49a611fddd1b631d68"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -4740,9 +4740,9 @@ dependencies = [
 
 [[package]]
 name = "syn"
-version = "2.0.20"
+version = "2.0.23"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fcb8d4cebc40aa517dfb69618fa647a346562e67228e2236ae0042ee6ac14775"
+checksum = "59fb7d6d8281a51045d62b8eb3a7d1ce347b76f312af50cd3dc0af39c87c1737"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -4796,7 +4796,7 @@ version = "0.1.0"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -4822,7 +4822,7 @@ checksum = "f9456a42c5b0d803c8cd86e73dd7cc9edd429499f37a3550d286d5e86720569f"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -5036,7 +5036,7 @@ checksum = "630bdcf245f78637c13ec01ffae6187cca34625e8c63150d424b59e55af2675e"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -5147,7 +5147,7 @@ checksum = "0f57e3ca2a01450b1a921183a9c9cbfda207fd822cef4ccb00a65402cbba7a74"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
@@ -5453,7 +5453,7 @@ dependencies = [
  "once_cell",
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
  "wasm-bindgen-shared",
 ]
 
@@ -5487,7 +5487,7 @@ checksum = "54681b18a46765f095758388f2d0cf16eb8d4169b639ab575a8f5693af210c7b"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
  "wasm-bindgen-backend",
  "wasm-bindgen-shared",
 ]
@@ -5994,7 +5994,7 @@ checksum = "ce36e65b0d2999d2aafac989fb249189a141aee1f53c612c1f37d72631959f69"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn 2.0.20",
+ "syn 2.0.23",
 ]
 
 [[package]]
diff --git a/Cargo.toml b/Cargo.toml
index a897a2300..acea046ac 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -131,7 +131,7 @@ sketching = { path = "./libs/sketching" }
 smartstring = "^1.0.1"
 smolset = "^1.3.1"
 sshkeys = "^0.3.1"
-syn = { version = "2.0.20", features = ["full"] }
+syn = { version = "2.0.23", features = ["full"] }
 testkit-macros = { path = "./server/testkit-macros" }
 tide = "^0.16.0"
 # Including brotli *very* slow, so don't do that. Including the "default" feature pulls a mime-type list from the internet on build, which isn't used.