diff --git a/Cargo.lock b/Cargo.lock
index cbc9053a69..1c3110e1be 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1260,9 +1260,9 @@ dependencies = [
 
 [[package]]
 name = "once_cell"
-version = "1.13.0"
+version = "1.13.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "18a6dbe30758c9f83eb00cbea4ac95966305f5a7772f3f42ebfc7fc7eddbd8e1"
+checksum = "074864da206b4973b84eb91683020dbefd6a8c3f0f38e054d93954e891935e4e"
 
 [[package]]
 name = "opaque-debug"
@@ -1657,6 +1657,7 @@ dependencies = [
  "glob",
  "log",
  "notify",
+ "once_cell",
  "rayon",
  "regex",
  "rustpython-parser",
diff --git a/Cargo.toml b/Cargo.toml
index 4b761c02fc..fce4a9c6a9 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -21,6 +21,7 @@ filetime = { version = "0.2.17" }
 glob = { version = "0.3.0"}
 log = { version = "0.4.17" }
 notify = { version = "4.0.17" }
+once_cell = { version = "1.13.1" }
 rayon = { version = "1.5.3" }
 regex = { version = "1.6.0" }
 rustpython-parser = { features = ["lalrpop"], git = "https://github.com/charliermarsh/RustPython.git", rev = "1613f6c6990011a4bc559e79aaf28d715f9f729b" }
diff --git a/src/checks.rs b/src/checks.rs
index 0ef927f0fb..26290c8017 100644
--- a/src/checks.rs
+++ b/src/checks.rs
@@ -1,6 +1,7 @@
 use std::str::FromStr;
 
 use anyhow::Result;
+use once_cell::sync::Lazy;
 use regex::Regex;
 use rustpython_parser::ast::Location;
 use serde::{Deserialize, Serialize};
@@ -162,14 +163,17 @@ pub struct Check {
     pub location: Location,
 }
 
+static NO_QA_REGEX: Lazy<Regex> = Lazy::new(|| {
+    Regex::new(r"(?i)# noqa(?::\s?(?P<codes>([A-Z]+[0-9]+(?:[,\s]+)?)+))?").expect("Invalid regex")
+});
+static SPLIT_COMMA_REGEX: Lazy<Regex> = Lazy::new(|| Regex::new(r"[,\s]").expect("Invalid regex"));
+
 impl Check {
     pub fn is_inline_ignored(&self, line: &str) -> bool {
-        let re = Regex::new(r"(?i)# noqa(?::\s?(?P<codes>([A-Z]+[0-9]+(?:[,\s]+)?)+))?").unwrap();
-        match re.captures(line) {
+        match NO_QA_REGEX.captures(line) {
             Some(caps) => match caps.name("codes") {
                 Some(codes) => {
-                    let re = Regex::new(r"[,\s]").unwrap();
-                    for code in re
+                    for code in SPLIT_COMMA_REGEX
                         .split(codes.as_str())
                         .map(|code| code.trim())
                         .filter(|code| !code.is_empty())