diff --git a/Cargo.lock b/Cargo.lock
index 626e896..e7cfe6d 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -11,21 +11,6 @@ dependencies = [
  "memchr",
 ]
 
-[[package]]
-name = "android-tzdata"
-version = "0.1.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e999941b234f3131b00bc13c22d06e8c5ff726d1b6318ac7eb276997bbb4fef0"
-
-[[package]]
-name = "android_system_properties"
-version = "0.1.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "819e7219dbd41043ac279b19830f2efc897156490d7fd6ea916720117ee66311"
-dependencies = [
- "libc",
-]
-
 [[package]]
 name = "anstream"
 version = "0.3.2"
@@ -114,12 +99,6 @@ dependencies = [
  "generic-array",
 ]
 
-[[package]]
-name = "bumpalo"
-version = "3.13.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a3e2c3daef883ecc1b5d58c15adae93470a91d425f3532ba1695849656af3fc1"
-
 [[package]]
 name = "byteorder"
 version = "1.4.3"
@@ -141,21 +120,6 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
-[[package]]
-name = "chrono"
-version = "0.4.26"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ec837a71355b28f6556dbd569b37b3f363091c0bd4b2e735674521b4c5fd9bc5"
-dependencies = [
- "android-tzdata",
- "iana-time-zone",
- "js-sys",
- "num-traits",
- "time",
- "wasm-bindgen",
- "winapi",
-]
-
 [[package]]
 name = "cipher"
 version = "0.4.4"
@@ -219,12 +183,6 @@ version = "0.9.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "28c122c3980598d243d63d9a704629a2d748d101f278052ff068be5a4423ab6f"
 
-[[package]]
-name = "core-foundation-sys"
-version = "0.8.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e496a50fda8aacccc86d7529e2c1e0892dbd0f898a6b5645b5561b89c3210efa"
-
 [[package]]
 name = "cpufeatures"
 version = "0.2.9"
@@ -405,7 +363,7 @@ checksum = "be4136b2a15dd319360be1c07d9933517ccf0be8f16bf62a3bee4f0d618df427"
 dependencies = [
  "cfg-if",
  "libc",
- "wasi 0.11.0+wasi-snapshot-preview1",
+ "wasi",
 ]
 
 [[package]]
@@ -455,29 +413,6 @@ version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9a3a5bfb195931eeb336b2a7b4d761daec841b97f947d34394601737a7bba5e4"
 
-[[package]]
-name = "iana-time-zone"
-version = "0.1.57"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2fad5b825842d2b38bd206f3e81d6957625fd7f0a361e345c30e01a0ae2dd613"
-dependencies = [
- "android_system_properties",
- "core-foundation-sys",
- "iana-time-zone-haiku",
- "js-sys",
- "wasm-bindgen",
- "windows",
-]
-
-[[package]]
-name = "iana-time-zone-haiku"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f31827a206f56af32e590ba56d5d2d085f558508192593743f16b2306495269f"
-dependencies = [
- "cc",
-]
-
 [[package]]
 name = "inout"
 version = "0.1.3"
@@ -498,15 +433,6 @@ dependencies = [
  "windows-sys",
 ]
 
-[[package]]
-name = "js-sys"
-version = "0.3.64"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c5f195fe497f702db0f318b07fdd68edb16955aed830df8363d837542f8f935a"
-dependencies = [
- "wasm-bindgen",
-]
-
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -959,17 +885,6 @@ dependencies = [
  "winapi-util",
 ]
 
-[[package]]
-name = "time"
-version = "0.1.45"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1b797afad3f312d1c66a56d11d0316f916356d11bd158fbc6ca6389ff6bf805a"
-dependencies = [
- "libc",
- "wasi 0.10.0+wasi-snapshot-preview1",
- "winapi",
-]
-
 [[package]]
 name = "typenum"
 version = "1.16.0"
@@ -1003,72 +918,12 @@ version = "0.9.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "49874b5167b65d7193b8aba1567f5c7d93d001cafc34600cee003eda787e483f"
 
-[[package]]
-name = "wasi"
-version = "0.10.0+wasi-snapshot-preview1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1a143597ca7c7793eff794def352d41792a93c481eb1042423ff7ff72ba2c31f"
-
 [[package]]
 name = "wasi"
 version = "0.11.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c8d87e72b64a3b4db28d11ce29237c246188f4f51057d65a7eab63b7987e423"
 
-[[package]]
-name = "wasm-bindgen"
-version = "0.2.87"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7706a72ab36d8cb1f80ffbf0e071533974a60d0a308d01a5d0375bf60499a342"
-dependencies = [
- "cfg-if",
- "wasm-bindgen-macro",
-]
-
-[[package]]
-name = "wasm-bindgen-backend"
-version = "0.2.87"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5ef2b6d3c510e9625e5fe6f509ab07d66a760f0885d858736483c32ed7809abd"
-dependencies = [
- "bumpalo",
- "log",
- "once_cell",
- "proc-macro2",
- "quote",
- "syn",
- "wasm-bindgen-shared",
-]
-
-[[package]]
-name = "wasm-bindgen-macro"
-version = "0.2.87"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "dee495e55982a3bd48105a7b947fd2a9b4a8ae3010041b9e0faab3f9cd028f1d"
-dependencies = [
- "quote",
- "wasm-bindgen-macro-support",
-]
-
-[[package]]
-name = "wasm-bindgen-macro-support"
-version = "0.2.87"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "54681b18a46765f095758388f2d0cf16eb8d4169b639ab575a8f5693af210c7b"
-dependencies = [
- "proc-macro2",
- "quote",
- "syn",
- "wasm-bindgen-backend",
- "wasm-bindgen-shared",
-]
-
-[[package]]
-name = "wasm-bindgen-shared"
-version = "0.2.87"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ca6ad05a4870b2bf5fe995117d3728437bd27d7cd5f06f13c17443ef369775a1"
-
 [[package]]
 name = "winapi"
 version = "0.3.9"
@@ -1100,15 +955,6 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
-[[package]]
-name = "windows"
-version = "0.48.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e686886bc078bc1b0b600cac0147aadb815089b6e4da64016cbd754b6342700f"
-dependencies = [
- "windows-targets",
-]
-
 [[package]]
 name = "windows-sys"
 version = "0.48.0"
@@ -1193,7 +1039,6 @@ name = "yubikey"
 version = "0.8.0-pre.0"
 dependencies = [
  "base16ct",
- "chrono",
  "der",
  "des",
  "ecdsa",
diff --git a/Cargo.toml b/Cargo.toml
index 3b79c2b..249841b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -23,7 +23,6 @@ members = [".", "cli"]
 x509-cert = { version = "0.2.3", features = [ "builder", "hazmat" ] }
 
 [dependencies]
-chrono = "0.4.23"
 der = "0.7.1"
 des = "0.8"
 elliptic-curve = "0.13"
@@ -44,7 +43,7 @@ rsa = { version = "0.9.2", features = ["sha2"] }
 secrecy = "0.8"
 sha1 = { version = "0.10", features = ["oid"] }
 sha2 = { version = "0.10", features = ["oid"] }
-signature = "2.0.0"
+signature = "2"
 subtle = "2"
 uuid = { version = "1.2", features = ["v4"] }
 x509-cert.workspace = true