diff --git a/Cargo.lock b/Cargo.lock
index 67eccc5..0bc6a94 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,12 +2,6 @@
 # It is not intended for manual editing.
 version = 3
 
-[[package]]
-name = "autocfg"
-version = "1.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
-
 [[package]]
 name = "cfg-if"
 version = "1.0.0"
@@ -30,16 +24,22 @@ dependencies = [
 name = "econf-derive"
 version = "0.2.1"
 dependencies = [
- "proc-macro2",
- "quote",
- "syn",
+ "proc-macro2 0.4.30",
+ "quote 0.6.13",
+ "syn 0.15.44",
 ]
 
+[[package]]
+name = "equivalent"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5443807d6dff69373d433ab9ef5378ad8df50ca6298caf15de6e52e24aaf54d5"
+
 [[package]]
 name = "hashbrown"
-version = "0.11.2"
+version = "0.14.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ab5ef0d4909ef3724cc8cce6ccc8572c5c817592e9285f5464f8e86f8bd3726e"
+checksum = "e5274423e17b7c9fc20b6e7e208532f9b19825d82dfd615708b70edd83df41f1"
 
 [[package]]
 name = "humantime"
@@ -49,25 +49,25 @@ checksum = "9a3a5bfb195931eeb336b2a7b4d761daec841b97f947d34394601737a7bba5e4"
 
 [[package]]
 name = "indexmap"
-version = "1.8.2"
+version = "2.2.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e6012d540c5baa3589337a98ce73408de9b5a25ec9fc2c6fd6be8f0d39e0ca5a"
+checksum = "168fb715dda47215e360912c096649d23d58bf392ac62f73919e831745e40f26"
 dependencies = [
- "autocfg",
+ "equivalent",
  "hashbrown",
 ]
 
 [[package]]
-name = "libc"
-version = "0.2.126"
+name = "itoa"
+version = "1.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "349d5a591cd28b49e1d1037471617a32ddcda5731b99419008085f72d5a53836"
+checksum = "49f1f14873335454500d59611f1cf4a4b0f786f9ac11f4312a78e4cf2566695b"
 
 [[package]]
-name = "linked-hash-map"
-version = "0.5.4"
+name = "libc"
+version = "0.2.126"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7fb9b38af92608140b86b693604b9ffcc5824240a484d1ecd4795bacb2fe88f3"
+checksum = "349d5a591cd28b49e1d1037471617a32ddcda5731b99419008085f72d5a53836"
 
 [[package]]
 name = "log"
@@ -87,13 +87,31 @@ dependencies = [
  "unicode-xid",
 ]
 
+[[package]]
+name = "proc-macro2"
+version = "1.0.86"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5e719e8df665df0d1c8fbfd238015744736151d4445ec0836b8e628aae103b77"
+dependencies = [
+ "unicode-ident",
+]
+
 [[package]]
 name = "quote"
 version = "0.6.13"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6ce23b6b870e8f94f81fb0a363d65d86675884b34a09043c81e5562f11c1f8e1"
 dependencies = [
- "proc-macro2",
+ "proc-macro2 0.4.30",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.36"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0fa76aaf39101c457836aec0ce2316dbdc3ab723cdda1c6bd4e6ad4208acaca7"
+dependencies = [
+ "proc-macro2 1.0.86",
 ]
 
 [[package]]
@@ -104,20 +122,35 @@ checksum = "f3f6f92acf49d1b98f7a81226834412ada05458b7364277387724a237f062695"
 
 [[package]]
 name = "serde"
-version = "1.0.137"
+version = "1.0.203"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "61ea8d54c77f8315140a05f4c7237403bf38b72704d031543aa1d16abbf517d1"
+checksum = "7253ab4de971e72fb7be983802300c30b5a7f0c2e56fab8abfc6a214307c0094"
+dependencies = [
+ "serde_derive",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.203"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "500cbc0ebeb6f46627f50f3f5811ccf6bf00643be300b4c3eabc0ef55dc5b5ba"
+dependencies = [
+ "proc-macro2 1.0.86",
+ "quote 1.0.36",
+ "syn 2.0.68",
+]
 
 [[package]]
 name = "serde_yaml"
-version = "0.8.24"
+version = "0.9.34+deprecated"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "707d15895415db6628332b737c838b88c598522e4dc70647e59b72312924aebc"
+checksum = "6a8b1a1a2ebf674015cc02edccce75287f1a0130d394307b36743c2f5d504b47"
 dependencies = [
  "indexmap",
+ "itoa",
  "ryu",
  "serde",
- "yaml-rust",
+ "unsafe-libyaml",
 ]
 
 [[package]]
@@ -136,11 +169,22 @@ version = "0.15.44"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9ca4b3b69a77cbe1ffc9e198781b7acb0c7365a883670e8f1c1bc66fba79a5c5"
 dependencies = [
- "proc-macro2",
- "quote",
+ "proc-macro2 0.4.30",
+ "quote 0.6.13",
  "unicode-xid",
 ]
 
+[[package]]
+name = "syn"
+version = "2.0.68"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "901fa70d88b9d6c98022e23b4136f9f3e54e4662c3bc1bd1d84a42a9a0f0c1e9"
+dependencies = [
+ "proc-macro2 1.0.86",
+ "quote 1.0.36",
+ "unicode-ident",
+]
+
 [[package]]
 name = "time"
 version = "0.1.44"
@@ -152,12 +196,24 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "unicode-ident"
+version = "1.0.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3354b9ac3fae1ff6755cb6db53683adb661634f67557942dea4facebec0fee4b"
+
 [[package]]
 name = "unicode-xid"
 version = "0.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fc72304796d0818e357ead4e000d19c9c174ab23dc11093ac919054d20a6a7fc"
 
+[[package]]
+name = "unsafe-libyaml"
+version = "0.2.11"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "673aac59facbab8a9007c7f6108d11f63b603f7cabff99fabf650fea5c32b861"
+
 [[package]]
 name = "wasi"
 version = "0.10.0+wasi-snapshot-preview1"
@@ -185,12 +241,3 @@ name = "winapi-x86_64-pc-windows-gnu"
 version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
-
-[[package]]
-name = "yaml-rust"
-version = "0.4.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "56c1936c4cc7a1c9ab21a1ebb602eb942ba868cbd44a99cb7cdc5892335e1c85"
-dependencies = [
- "linked-hash-map",
-]
diff --git a/econf/Cargo.toml b/econf/Cargo.toml
index 157eb7f..0ab0a6b 100644
--- a/econf/Cargo.toml
+++ b/econf/Cargo.toml
@@ -13,7 +13,7 @@ readme = "README.md"
 [dependencies]
 log = "0.4"
 serde = "1.0"
-serde_yaml = "0.8"
+serde_yaml = "0.9"
 econf-derive = { version = "0.2.1", path = "../econf-derive" }
 humantime = "2.1"