diff --git a/Cargo.lock b/Cargo.lock
index e57cd2d..b127814 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -182,9 +182,9 @@ dependencies = [
 name = "furigana_gen"
 version = "0.1.0"
 dependencies = [
+ "lz4_flex",
  "once_cell",
  "regex",
- "ruzstd",
  "vibrato",
 ]
 
@@ -256,6 +256,15 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "lz4_flex"
+version = "0.11.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "75761162ae2b0e580d7e7c390558127e5f01b4194debd6221fd8c207fc80e3f5"
+dependencies = [
+ "twox-hash",
+]
+
 [[package]]
 name = "memchr"
 version = "2.7.4"
@@ -441,16 +450,6 @@ version = "1.0.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "955d28af4278de8121b7ebeb796b6a45735dc01436d898801014aced2773a3d6"
 
-[[package]]
-name = "ruzstd"
-version = "0.7.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1c8b8f3d26bd9f945e5cbae77f7cdfbf37af9a66956f1115eb4516e45df519f4"
-dependencies = [
- "byteorder",
- "twox-hash",
-]
-
 [[package]]
 name = "ryu"
 version = "1.0.18"
diff --git a/Cargo.toml b/Cargo.toml
index 8db4433..13ffae0 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -7,6 +7,6 @@ edition = "2021"
 
 [dependencies]
 vibrato = "0.5"
-ruzstd = "0.7"
+lz4_flex = "0.11"
 regex = "1.10"
 once_cell = "1.19"
diff --git a/dictionary/system.dic b/dictionary/system.dic
new file mode 100644
index 0000000..f2186f4
Binary files /dev/null and b/dictionary/system.dic differ
diff --git a/dictionary/system.dic.lz4 b/dictionary/system.dic.lz4
new file mode 100644
index 0000000..af5769d
Binary files /dev/null and b/dictionary/system.dic.lz4 differ
diff --git a/dictionary/system.dic.xz b/dictionary/system.dic.xz
new file mode 100644
index 0000000..7cb1e03
Binary files /dev/null and b/dictionary/system.dic.xz differ
diff --git a/dictionary/system.dic.zst b/dictionary/system.dic.zst
deleted file mode 100644
index 7a24093..0000000
Binary files a/dictionary/system.dic.zst and /dev/null differ
diff --git a/src/main.rs b/src/main.rs
index 5e7bbbe..f8365cb 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -3,17 +3,23 @@ use std::{
     io::{Cursor, Read},
 };
 
+use lz4_flex::frame::FrameDecoder;
 use once_cell::sync::Lazy;
 use regex::Regex;
-use ruzstd::StreamingDecoder;
 use vibrato::{Dictionary, Tokenizer};
 
-const DICT: &[u8] = include_bytes!("../dictionary/system.dic.zst");
+const DICT: &[u8] = include_bytes!("../dictionary/system.dic.lz4");
 
 fn main() {
     let dict = {
-        let decoder = StreamingDecoder::new(Cursor::new(DICT)).unwrap();
-        Dictionary::read(decoder).unwrap()
+        // Note: we could just pass the decoder straight to `Dictionary::read()`
+        // below, and it would work.  However, that ends up being slower than
+        // first decompressing the whole thing ahead of time.
+        let mut decoder = FrameDecoder::new(Cursor::new(DICT));
+        let mut data = Vec::new();
+        decoder.read_to_end(&mut data).unwrap();
+
+        Dictionary::read(Cursor::new(&data)).unwrap()
     };
 
     let text = {