diff --git a/Cargo.lock b/Cargo.lock
index 41e444b..c3e39d8 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -13,9 +13,9 @@ dependencies = [
 
 [[package]]
 name = "autocfg"
-version = "1.0.1"
+version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cdb031dd78e28731d87d56cc8ffef4a8f36ca26c38fe2de700543e627f8a464a"
+checksum = "d468802bab17cbc0cc575e9b053f41e72aa36bfa6b7f55e3529ffa43161b97fa"
 
 [[package]]
 name = "bitflags"
@@ -185,9 +185,9 @@ dependencies = [
 
 [[package]]
 name = "hashbrown"
-version = "0.11.2"
+version = "0.12.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ab5ef0d4909ef3724cc8cce6ccc8572c5c817592e9285f5464f8e86f8bd3726e"
+checksum = "8a9ee70c43aaf417c914396645a0fa852624801b24ebb7ae78fe8272889ac888"
 
 [[package]]
 name = "hermit-abi"
@@ -224,9 +224,9 @@ checksum = "ce23b50ad8242c51a442f3ff322d56b02f08852c77e4c0b4d3fd684abc89c683"
 
 [[package]]
 name = "indexmap"
-version = "1.7.0"
+version = "1.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "bc633605454125dec4b66843673f01c7df2b89479b32e0ed634e43a91cff62a5"
+checksum = "10a35a97730320ffe8e2d410b5d3b69279b98d2c14bdb8b70ea89ecf7888d41e"
 dependencies = [
  "autocfg",
  "hashbrown",
@@ -241,6 +241,12 @@ dependencies = [
  "cfg-if",
 ]
 
+[[package]]
+name = "itoa"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4217ad341ebadf8d8e724e264f13e593e0648f5b3e94b3896a5df283be015ecc"
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -253,12 +259,6 @@ version = "0.2.112"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1b03d17f364a3a042d5e5d46b053bbbf82c92c9430c592dd4c064dc6ee997125"
 
-[[package]]
-name = "linked-hash-map"
-version = "0.5.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7fb9b38af92608140b86b693604b9ffcc5824240a484d1ecd4795bacb2fe88f3"
-
 [[package]]
 name = "log"
 version = "0.4.14"
@@ -465,9 +465,9 @@ dependencies = [
 
 [[package]]
 name = "ryu"
-version = "1.0.9"
+version = "1.0.11"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "73b4b750c782965c211b42f022f59af1fbceabdd026623714f104152f1ec149f"
+checksum = "4501abdff3ae82a1c1b477a17252eb69cee9e66eb915c1abaa4f44d873df9f09"
 
 [[package]]
 name = "same-file"
@@ -486,20 +486,21 @@ checksum = "d29ab0c6d3fc0ee92fe66e2d99f700eab17a8d57d1c1d3b748380fb20baa78cd"
 
 [[package]]
 name = "serde"
-version = "1.0.132"
+version = "1.0.147"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8b9875c23cf305cd1fd7eb77234cbb705f21ea6a72c637a5c6db5fe4b8e7f008"
+checksum = "d193d69bae983fc11a79df82342761dfbf28a99fc8d203dca4c3c1b590948965"
 
 [[package]]
 name = "serde_yaml"
-version = "0.8.26"
+version = "0.9.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "578a7433b776b56a35785ed5ce9a7e777ac0598aac5a6dd1b4b18a307c7fc71b"
+checksum = "6d232d893b10de3eb7258ff01974d6ee20663d8e833263c99409d4b13a0209da"
 dependencies = [
  "indexmap",
+ "itoa",
  "ryu",
  "serde",
- "yaml-rust",
+ "unsafe-libyaml",
 ]
 
 [[package]]
@@ -587,6 +588,12 @@ version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ccb82d61f80a663efe1f787a51b16b5a51e3314d6ac365b08639f52387b33f3"
 
+[[package]]
+name = "unsafe-libyaml"
+version = "0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c1e5fa573d8ac5f1a856f8d7be41d390ee973daf97c806b2c1a465e4e1406e68"
+
 [[package]]
 name = "version_check"
 version = "0.9.4"
@@ -635,15 +642,6 @@ 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",
-]
-
 [[package]]
 name = "yansi"
 version = "0.5.1"
diff --git a/Cargo.toml b/Cargo.toml
index 31dac85..f577ade 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -36,7 +36,7 @@ pulldown-cmark = "0.9.2"
 pulldown-cmark-to-cmark = "9.0.0"
 rayon = "1.5.3"
 regex = "1.6.0"
-serde_yaml = "0.8.26"
+serde_yaml = "0.9.14"
 slug = "0.1.4"
 snafu = "0.6.10"
 
diff --git a/src/frontmatter.rs b/src/frontmatter.rs
index 2637815..6d3d387 100644
--- a/src/frontmatter.rs
+++ b/src/frontmatter.rs
@@ -40,6 +40,7 @@ pub fn frontmatter_to_str(frontmatter: Frontmatter) -> Result<String> {
     }
 
     let mut buffer = String::new();
+    buffer.push_str("---\n");
     buffer.push_str(&serde_yaml::to_string(&frontmatter)?);
     buffer.push_str("---\n");
     Ok(buffer)