diff --git a/Cargo.lock b/Cargo.lock
index e46474a8..3e68a245 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -301,6 +301,33 @@ dependencies = [
  "zeroize",
 ]
 
+[[package]]
+name = "curve25519-dalek"
+version = "4.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f711ade317dd348950a9910f81c5947e3d8907ebd2b83f76203ff1807e6a2bc2"
+dependencies = [
+ "cfg-if",
+ "cpufeatures",
+ "curve25519-dalek-derive",
+ "fiat-crypto",
+ "platforms",
+ "rustc_version",
+ "subtle",
+ "zeroize",
+]
+
+[[package]]
+name = "curve25519-dalek-derive"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "83fdaf97f4804dcebfa5862639bc9ce4121e82140bec2a987ac5140294865b5b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.26",
+]
+
 [[package]]
 name = "derive_more"
 version = "0.99.17"
@@ -344,6 +371,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "fiat-crypto"
+version = "0.1.20"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e825f6987101665dea6ec934c09ec6d721de7bc1bf92248e1d5810c8cd636b77"
+
 [[package]]
 name = "fnv"
 version = "1.0.7"
@@ -720,6 +753,12 @@ version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8b870d8c151b6f2fb93e84a13146138f05d02ed11c7e7c54f8826aaaf7c9f184"
 
+[[package]]
+name = "platforms"
+version = "3.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e3d7ddaed09e0eb771a79ab0fd64609ba0afb0a8366421957936ad14cbd13630"
+
 [[package]]
 name = "ppoprf"
 version = "0.2.1"
@@ -729,7 +768,7 @@ dependencies = [
  "base64 0.13.1",
  "bincode",
  "bitvec",
- "curve25519-dalek",
+ "curve25519-dalek 3.2.0",
  "derive_more",
  "rand",
  "rand_core 0.5.1",
@@ -1016,7 +1055,7 @@ dependencies = [
  "axum",
  "base64 0.21.2",
  "clap",
- "curve25519-dalek",
+ "curve25519-dalek 4.0.0",
  "hyper",
  "ppoprf",
  "rand_core 0.5.1",
diff --git a/Cargo.toml b/Cargo.toml
index 87abc068..84743687 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -10,7 +10,7 @@ edition = "2021"
 axum = "0.6.19"
 base64 = "0.21.2"
 clap = { version = "4.3.17", features = ["derive"] }
-curve25519-dalek = "3.2.0"
+curve25519-dalek = "4.0.0"
 ppoprf = "0.2.1"
 rlimit = "0.10"
 serde = "1.0.179"