diff --git a/Cargo.lock b/Cargo.lock
index 90c7b5f..f05e6f6 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -2,6 +2,12 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "Inflector"
+version = "0.11.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fe438c63458706e03479442743baae6c88256498e6431708f6dfc520a26515d3"
+
 [[package]]
 name = "addr2line"
 version = "0.22.0"
@@ -28,6 +34,46 @@ dependencies = [
  "cpufeatures",
 ]
 
+[[package]]
+name = "aformat"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "888c88fe52c66481cc389ba777a85715b1868b76cfd37e018911f89bc9a84388"
+dependencies = [
+ "aformat-macros",
+ "to-arraystring",
+ "typenum",
+ "typenum_mappings",
+]
+
+[[package]]
+name = "aformat-macros"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f1d3370253838699d84eb0eba50100317518c8dc4cdf69ddbcba7a4e9938f09e"
+dependencies = [
+ "bytestring",
+ "proc-macro2",
+ "procout",
+ "quote",
+ "syn 2.0.72",
+]
+
+[[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 = "anyhow"
 version = "1.0.86"
@@ -40,6 +86,12 @@ version = "1.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "69f7f8c3906b62b754cd5326047894316021dcfe5a194c8ea52bdd94934a3457"
 
+[[package]]
+name = "arrayvec"
+version = "0.7.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "96d30a06541fbafbc7f82ed10c06164cfbd2c401138f6addd8404629c4b16711"
+
 [[package]]
 name = "async-trait"
 version = "0.1.81"
@@ -48,7 +100,7 @@ checksum = "6e0c28dcc82d7c8ead5cb13beb15405b57b8546e93215673ff8ca0349a028107"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.72",
 ]
 
 [[package]]
@@ -536,6 +588,15 @@ dependencies = [
  "either",
 ]
 
+[[package]]
+name = "bytestring"
+version = "1.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "74d80203ea6b29df88012294f62733de21cfeab47f17b41af3a38bc30a03ee72"
+dependencies = [
+ "bytes",
+]
+
 [[package]]
 name = "cbc"
 version = "0.1.2"
@@ -557,6 +618,20 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
+[[package]]
+name = "chrono"
+version = "0.4.38"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a21f936df1771bf62b77f047b726c4625ff2e8aa607c01ec06e5a05bd8463401"
+dependencies = [
+ "android-tzdata",
+ "iana-time-zone",
+ "js-sys",
+ "num-traits",
+ "wasm-bindgen",
+ "windows-targets 0.52.6",
+]
+
 [[package]]
 name = "cipher"
 version = "0.4.4"
@@ -1017,6 +1092,29 @@ dependencies = [
  "tracing",
 ]
 
+[[package]]
+name = "iana-time-zone"
+version = "0.1.60"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e7ffbb5a1b541ea2561f8c41c087286cc091e21e556a4f09a8f6cbf17b69b141"
+dependencies = [
+ "android_system_properties",
+ "core-foundation-sys",
+ "iana-time-zone-haiku",
+ "js-sys",
+ "wasm-bindgen",
+ "windows-core",
+]
+
+[[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 = "idna"
 version = "0.5.0"
@@ -1327,7 +1425,7 @@ checksum = "2f38a4412a78282e09a2cf38d195ea5420d15ba0602cb375210efbc877243965"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.72",
 ]
 
 [[package]]
@@ -1366,6 +1464,19 @@ dependencies = [
  "unicode-ident",
 ]
 
+[[package]]
+name = "procout"
+version = "0.1.13"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9d710f595d4e0a6df3265e2fc65731ee564ada41400628563fe635905ab70418"
+dependencies = [
+ "Inflector",
+ "chrono",
+ "proc-macro2",
+ "quote",
+ "syn 1.0.109",
+]
+
 [[package]]
 name = "quinn"
 version = "0.11.3"
@@ -1753,7 +1864,7 @@ checksum = "e0cd7e117be63d3c3678776753929474f3b04a43a080c744d6b0ae2a8c28e222"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.72",
 ]
 
 [[package]]
@@ -1877,6 +1988,17 @@ version = "2.6.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "13c2bddecc57b384dee18652358fb23172facb8a2c51ccc10d74c157bdea3292"
 
+[[package]]
+name = "syn"
+version = "1.0.109"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "72b64191b275b66ffe2469e8af2c1cfe3bafa67b529ead792a6d0160888b4237"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-ident",
+]
+
 [[package]]
 name = "syn"
 version = "2.0.72"
@@ -1917,7 +2039,7 @@ checksum = "a4558b58466b9ad7ca0f102865eccc95938dca1a74a856f2b57b6629050da261"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.72",
 ]
 
 [[package]]
@@ -1976,6 +2098,17 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1f3ccbac311fea05f86f61904b462b55fb3df8837a366dfc601a0161d0532f20"
 
+[[package]]
+name = "to-arraystring"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0fafaa22f176928fb926345e78eb2ec404603c878b274e6ab1f76de1f6dde1b1"
+dependencies = [
+ "arrayvec",
+ "itoa",
+ "ryu",
+]
+
 [[package]]
 name = "tokio"
 version = "1.39.2"
@@ -2002,7 +2135,7 @@ checksum = "693d596312e88961bc67d7f1f97af8a70227d9f90c31bba5806eec004978d752"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.72",
 ]
 
 [[package]]
@@ -2085,7 +2218,7 @@ checksum = "34704c8d6ebcbc939824180af020566b01a7c01f80641264eba0999f6c2b6be7"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.72",
 ]
 
 [[package]]
@@ -2121,6 +2254,7 @@ checksum = "e421abadd41a4225275504ea4d6566923418b7f05506fbc9c0fe86ba7396114b"
 name = "tts-service"
 version = "0.1.0"
 dependencies = [
+ "aformat",
  "anyhow",
  "aws-config",
  "aws-sdk-polly",
@@ -2152,6 +2286,18 @@ version = "1.17.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "42ff0bf0c66b8238c6f3b578df37d0b7848e55df8577b3f74f92a69acceeb825"
 
+[[package]]
+name = "typenum_mappings"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0cbc2d8952dd1e08b0164a5b51549e80631ac9da4107669d26c8ea89cb0b5545"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn 2.0.72",
+ "to-arraystring",
+]
+
 [[package]]
 name = "unicode-bidi"
 version = "0.3.15"
@@ -2250,7 +2396,7 @@ dependencies = [
  "once_cell",
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.72",
  "wasm-bindgen-shared",
 ]
 
@@ -2284,7 +2430,7 @@ checksum = "e94f17b526d0a461a191c78ea52bbce64071ed5c04c9ffe424dcb38f74171bb7"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.72",
  "wasm-bindgen-backend",
  "wasm-bindgen-shared",
 ]
@@ -2336,6 +2482,15 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 
+[[package]]
+name = "windows-core"
+version = "0.52.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "33ab640c8d7e35bf8ba19b884ba838ceb4fba93a4e8c65a9059d08afcfc683d9"
+dependencies = [
+ "windows-targets 0.52.6",
+]
+
 [[package]]
 name = "windows-sys"
 version = "0.48.0"
@@ -2509,7 +2664,7 @@ checksum = "fa4f8080344d4671fb4e831a13ad1e68092748387dfc4f55e356242fae12ce3e"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.72",
 ]
 
 [[package]]
@@ -2529,5 +2684,5 @@ checksum = "ce36e65b0d2999d2aafac989fb249189a141aee1f53c612c1f37d72631959f69"
 dependencies = [
  "proc-macro2",
  "quote",
- "syn",
+ "syn 2.0.72",
 ]
diff --git a/Cargo.toml b/Cargo.toml
index efe27b2..b6ced4a 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -23,6 +23,7 @@ itertools = "0.13"
 aws-sdk-polly = "1.7.0"
 small-fixed-array = { version = "0.4.0", features = ["serde"] }
 memchr = "2.7.4"
+aformat = "0.1.4"
 
 [dependencies.fernet]
 version = "0.2"
diff --git a/src/espeak.rs b/src/espeak.rs
index 90b9826..2ccd275 100644
--- a/src/espeak.rs
+++ b/src/espeak.rs
@@ -1,5 +1,6 @@
 use std::sync::{LazyLock, OnceLock};
 
+use aformat::{aformat, CapStr, ToArrayString};
 use memchr::memmem::Finder;
 use reqwest::header::HeaderValue;
 use tokio::io::AsyncReadExt;
@@ -25,6 +26,7 @@ pub async fn get_tts(
         anyhow::bail!("Invalid voice: {voice}");
     }
 
+    let voice = CapStr::<8>(voice);
     let Finders {
         repeat_err,
         replaced_with_err,
@@ -41,9 +43,9 @@ pub async fn get_tts(
                 "--pho",
                 "-q",
                 "-s",
-                &speaking_rate.to_string(),
+                &speaking_rate.to_arraystring(),
                 "-v",
-                &format!("mb/mb-{voice}"),
+                &aformat!("mb/mb-{voice}"),
                 text,
             ])
             .spawn()?;
@@ -59,7 +61,7 @@ pub async fn get_tts(
             .stdin(espeak_stdout)
             .args([
                 "-e",
-                &format!("/usr/share/mbrola/{voice}/{voice}"),
+                &aformat!("/usr/share/mbrola/{voice}/{voice}"),
                 "-",
                 "-.wav",
             ])
diff --git a/src/gtts.rs b/src/gtts.rs
index 81cdbb2..4d41c31 100644
--- a/src/gtts.rs
+++ b/src/gtts.rs
@@ -1,5 +1,6 @@
 use std::sync::OnceLock;
 
+use aformat::ToArrayString;
 use ipgen::IpNetwork;
 use itertools::Itertools;
 use rand::Rng;
@@ -31,7 +32,7 @@ fn parse_url(text: &str, lang: &str) -> reqwest::Url {
     url.query_pairs_mut()
         .append_pair("tl", lang)
         .append_pair("q", text)
-        .append_pair("textlen", &text.len().to_string())
+        .append_pair("textlen", &text.len().to_arraystring())
         .finish();
     url
 }