diff --git a/Cargo.lock b/Cargo.lock
index 847debdc..474dc1be 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -3394,7 +3394,7 @@ dependencies = [
  "convert_case",
  "csv",
  "futures-util",
- "reqwest",
+ "hyper",
  "serde",
  "tokio",
  "tracing",
diff --git a/crates/iana-codegen/Cargo.toml b/crates/iana-codegen/Cargo.toml
index 4472ef41..9d445b12 100644
--- a/crates/iana-codegen/Cargo.toml
+++ b/crates/iana-codegen/Cargo.toml
@@ -12,8 +12,8 @@ camino = "1.1.4"
 convert_case = "0.6.0"
 csv = "1.2.1"
 futures-util = "0.3.28"
-reqwest = { version = "0.11.16", features = ["blocking", "rustls-tls"], default-features = false }
+hyper = { version = "0.14.16", features = ["tcp", "client", "http1"] }
 serde = { version = "1.0.160", features = ["derive"] }
-tokio = { version = "1.27.0", features = ["full"] }
+tokio = { version = "1.27.0", features = ["macros", "rt-multi-thread", "fs", "io-util"] }
 tracing = "0.1.37"
 tracing-subscriber = "0.3.16"
diff --git a/crates/iana-codegen/src/jose.rs b/crates/iana-codegen/src/jose.rs
index a23561f7..ee2f409a 100644
--- a/crates/iana-codegen/src/jose.rs
+++ b/crates/iana-codegen/src/jose.rs
@@ -62,7 +62,7 @@ pub struct WebEncryptionSignatureAlgorithm {
 
 impl EnumEntry for WebEncryptionSignatureAlgorithm {
     const URL: &'static str =
-        "https://www.iana.org/assignments/jose/web-signature-encryption-algorithms.csv";
+        "http://www.iana.org/assignments/jose/web-signature-encryption-algorithms.csv";
     const SECTIONS: &'static [Section] = &[
         s(
             "JsonWebSignatureAlg",
@@ -126,7 +126,7 @@ pub struct WebEncryptionCompressionAlgorithm {
 
 impl EnumEntry for WebEncryptionCompressionAlgorithm {
     const URL: &'static str =
-        "https://www.iana.org/assignments/jose/web-encryption-compression-algorithms.csv";
+        "http://www.iana.org/assignments/jose/web-encryption-compression-algorithms.csv";
     const SECTIONS: &'static [Section] = &[s(
         "JsonWebEncryptionCompressionAlgorithm",
         "JSON Web Encryption Compression Algorithm",
@@ -161,7 +161,7 @@ pub struct WebKeyType {
 }
 
 impl EnumEntry for WebKeyType {
-    const URL: &'static str = "https://www.iana.org/assignments/jose/web-key-types.csv";
+    const URL: &'static str = "http://www.iana.org/assignments/jose/web-key-types.csv";
     const SECTIONS: &'static [Section] = &[s("JsonWebKeyType", "JSON Web Key Type")];
 
     fn key(&self) -> Option<&'static str> {
@@ -193,7 +193,7 @@ pub struct WebKeyEllipticCurve {
 }
 
 impl EnumEntry for WebKeyEllipticCurve {
-    const URL: &'static str = "https://www.iana.org/assignments/jose/web-key-elliptic-curve.csv";
+    const URL: &'static str = "http://www.iana.org/assignments/jose/web-key-elliptic-curve.csv";
     const SECTIONS: &'static [Section] = &[
         s(
             "JsonWebKeyEcEllipticCurve",
@@ -236,7 +236,7 @@ pub struct WebKeyUse {
 }
 
 impl EnumEntry for WebKeyUse {
-    const URL: &'static str = "https://www.iana.org/assignments/jose/web-key-use.csv";
+    const URL: &'static str = "http://www.iana.org/assignments/jose/web-key-use.csv";
     const SECTIONS: &'static [Section] = &[s("JsonWebKeyUse", "JSON Web Key Use")];
 
     fn key(&self) -> Option<&'static str> {
@@ -266,7 +266,7 @@ pub struct WebKeyOperation {
 }
 
 impl EnumEntry for WebKeyOperation {
-    const URL: &'static str = "https://www.iana.org/assignments/jose/web-key-operations.csv";
+    const URL: &'static str = "http://www.iana.org/assignments/jose/web-key-operations.csv";
     const SECTIONS: &'static [Section] = &[s("JsonWebKeyOperation", "JSON Web Key Operation")];
 
     fn key(&self) -> Option<&'static str> {
diff --git a/crates/iana-codegen/src/main.rs b/crates/iana-codegen/src/main.rs
index f3303be2..ca2128b0 100644
--- a/crates/iana-codegen/src/main.rs
+++ b/crates/iana-codegen/src/main.rs
@@ -19,10 +19,11 @@
 use std::{collections::HashMap, fmt::Display, sync::Arc};
 
 use camino::{Utf8Path, Utf8PathBuf};
-use reqwest::Client;
 use tokio::io::AsyncWriteExt;
 use tracing::Level;
 
+type Client = hyper::Client<hyper::client::HttpConnector>;
+
 mod gen;
 pub mod jose;
 pub mod oauth;
@@ -208,7 +209,7 @@ async fn main() -> anyhow::Result<()> {
         .pretty()
         .init();
 
-    let client = Client::builder().user_agent("iana-parser/0.0.1").build()?;
+    let client = Client::new();
     let client = Arc::new(client);
 
     let iana_crate_root = Utf8Path::new("crates/iana/");
diff --git a/crates/iana-codegen/src/oauth.rs b/crates/iana-codegen/src/oauth.rs
index e21b6768..262b470c 100644
--- a/crates/iana-codegen/src/oauth.rs
+++ b/crates/iana-codegen/src/oauth.rs
@@ -35,7 +35,7 @@ pub struct AccessTokenType {
 }
 
 impl EnumEntry for AccessTokenType {
-    const URL: &'static str = "https://www.iana.org/assignments/oauth-parameters/token-types.csv";
+    const URL: &'static str = "http://www.iana.org/assignments/oauth-parameters/token-types.csv";
     const SECTIONS: &'static [Section] = &[s("OAuthAccessTokenType", "OAuth Access Token Type")];
 
     fn key(&self) -> Option<&'static str> {
@@ -59,7 +59,7 @@ pub struct AuthorizationEndpointResponseType {
 }
 
 impl EnumEntry for AuthorizationEndpointResponseType {
-    const URL: &'static str = "https://www.iana.org/assignments/oauth-parameters/endpoint.csv";
+    const URL: &'static str = "http://www.iana.org/assignments/oauth-parameters/endpoint.csv";
     const SECTIONS: &'static [Section] = &[s(
         "OAuthAuthorizationEndpointResponseType",
         "OAuth Authorization Endpoint Response Type",
@@ -98,7 +98,7 @@ pub struct TokenTypeHint {
 
 impl EnumEntry for TokenTypeHint {
     const URL: &'static str =
-        "https://www.iana.org/assignments/oauth-parameters/token-type-hint.csv";
+        "http://www.iana.org/assignments/oauth-parameters/token-type-hint.csv";
     const SECTIONS: &'static [Section] = &[s("OAuthTokenTypeHint", "OAuth Token Type Hint")];
 
     fn key(&self) -> Option<&'static str> {
@@ -112,7 +112,7 @@ impl EnumEntry for TokenTypeHint {
 
 impl EnumEntry for TokenEndpointAuthenticationMethod {
     const URL: &'static str =
-        "https://www.iana.org/assignments/oauth-parameters/token-endpoint-auth-method.csv";
+        "http://www.iana.org/assignments/oauth-parameters/token-endpoint-auth-method.csv";
     const SECTIONS: &'static [Section] = &[s(
         "OAuthClientAuthenticationMethod",
         "OAuth Token Endpoint Authentication Method",
@@ -140,7 +140,7 @@ pub struct PkceCodeChallengeMethod {
 
 impl EnumEntry for PkceCodeChallengeMethod {
     const URL: &'static str =
-        "https://www.iana.org/assignments/oauth-parameters/pkce-code-challenge-method.csv";
+        "http://www.iana.org/assignments/oauth-parameters/pkce-code-challenge-method.csv";
     const SECTIONS: &'static [Section] =
         &[s("PkceCodeChallengeMethod", "PKCE Code Challenge Method")];
 
diff --git a/crates/iana-codegen/src/traits.rs b/crates/iana-codegen/src/traits.rs
index ba95d820..7c900608 100644
--- a/crates/iana-codegen/src/traits.rs
+++ b/crates/iana-codegen/src/traits.rs
@@ -15,9 +15,11 @@
 use anyhow::Context;
 use async_trait::async_trait;
 use convert_case::{Case, Casing};
-use reqwest::Client;
+use hyper::http;
 use serde::de::DeserializeOwned;
 
+use super::Client;
+
 #[derive(Debug, Clone)]
 pub struct Section {
     pub key: &'static str,
@@ -72,12 +74,19 @@ pub trait EnumEntry: DeserializeOwned + Send + Sync {
 
     async fn fetch(client: &Client) -> anyhow::Result<Vec<(&'static str, EnumMember)>> {
         tracing::info!("Fetching CSV");
-        let body = client
-            .get(Self::URL)
-            .send()
+        let request = http::Request::get(Self::URL)
+            .header("User-Agent", "mas-iana-codegen/0.1")
+            .body(hyper::Body::empty())?;
+
+        let response = client
+            .request(request)
             .await
-            .context(format!("can't the CSV at {}", Self::URL))?
-            .bytes()
+            .context(format!("can't the CSV at {}", Self::URL))?;
+
+        let status = response.status();
+        anyhow::ensure!(status.is_success(), "HTTP status code is not 200: {status}");
+
+        let body = hyper::body::to_bytes(response.into_body())
             .await
             .context(format!("can't the CSV body at {}", Self::URL))?;
 
diff --git a/crates/iana/src/jose.rs b/crates/iana/src/jose.rs
index 99f031e5..37411c3c 100644
--- a/crates/iana/src/jose.rs
+++ b/crates/iana/src/jose.rs
@@ -19,7 +19,7 @@
 
 /// JSON Web Signature "alg" parameter
 ///
-/// Source: <https://www.iana.org/assignments/jose/web-signature-encryption-algorithms.csv>
+/// Source: <http://www.iana.org/assignments/jose/web-signature-encryption-algorithms.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum JsonWebSignatureAlg {
@@ -365,7 +365,7 @@ impl schemars::JsonSchema for JsonWebSignatureAlg {
 
 /// JSON Web Encryption "alg" parameter
 ///
-/// Source: <https://www.iana.org/assignments/jose/web-signature-encryption-algorithms.csv>
+/// Source: <http://www.iana.org/assignments/jose/web-signature-encryption-algorithms.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum JsonWebEncryptionAlg {
@@ -783,7 +783,7 @@ impl schemars::JsonSchema for JsonWebEncryptionAlg {
 
 /// JSON Web Encryption "enc" parameter
 ///
-/// Source: <https://www.iana.org/assignments/jose/web-signature-encryption-algorithms.csv>
+/// Source: <http://www.iana.org/assignments/jose/web-signature-encryption-algorithms.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum JsonWebEncryptionEnc {
@@ -967,7 +967,7 @@ impl schemars::JsonSchema for JsonWebEncryptionEnc {
 
 /// JSON Web Encryption Compression Algorithm
 ///
-/// Source: <https://www.iana.org/assignments/jose/web-encryption-compression-algorithms.csv>
+/// Source: <http://www.iana.org/assignments/jose/web-encryption-compression-algorithms.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum JsonWebEncryptionCompressionAlgorithm {
@@ -1061,7 +1061,7 @@ impl schemars::JsonSchema for JsonWebEncryptionCompressionAlgorithm {
 
 /// JSON Web Key Type
 ///
-/// Source: <https://www.iana.org/assignments/jose/web-key-types.csv>
+/// Source: <http://www.iana.org/assignments/jose/web-key-types.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum JsonWebKeyType {
@@ -1209,7 +1209,7 @@ impl schemars::JsonSchema for JsonWebKeyType {
 
 /// JSON Web Key EC Elliptic Curve
 ///
-/// Source: <https://www.iana.org/assignments/jose/web-key-elliptic-curve.csv>
+/// Source: <http://www.iana.org/assignments/jose/web-key-elliptic-curve.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum JsonWebKeyEcEllipticCurve {
@@ -1357,7 +1357,7 @@ impl schemars::JsonSchema for JsonWebKeyEcEllipticCurve {
 
 /// JSON Web Key OKP Elliptic Curve
 ///
-/// Source: <https://www.iana.org/assignments/jose/web-key-elliptic-curve.csv>
+/// Source: <http://www.iana.org/assignments/jose/web-key-elliptic-curve.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum JsonWebKeyOkpEllipticCurve {
@@ -1505,7 +1505,7 @@ impl schemars::JsonSchema for JsonWebKeyOkpEllipticCurve {
 
 /// JSON Web Key Use
 ///
-/// Source: <https://www.iana.org/assignments/jose/web-key-use.csv>
+/// Source: <http://www.iana.org/assignments/jose/web-key-use.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum JsonWebKeyUse {
@@ -1617,7 +1617,7 @@ impl schemars::JsonSchema for JsonWebKeyUse {
 
 /// JSON Web Key Operation
 ///
-/// Source: <https://www.iana.org/assignments/jose/web-key-operations.csv>
+/// Source: <http://www.iana.org/assignments/jose/web-key-operations.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum JsonWebKeyOperation {
diff --git a/crates/iana/src/oauth.rs b/crates/iana/src/oauth.rs
index 677a4df7..76b9b365 100644
--- a/crates/iana/src/oauth.rs
+++ b/crates/iana/src/oauth.rs
@@ -19,7 +19,7 @@
 
 /// OAuth Access Token Type
 ///
-/// Source: <https://www.iana.org/assignments/oauth-parameters/token-types.csv>
+/// Source: <http://www.iana.org/assignments/oauth-parameters/token-types.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum OAuthAccessTokenType {
@@ -128,7 +128,7 @@ impl schemars::JsonSchema for OAuthAccessTokenType {
 
 /// OAuth Authorization Endpoint Response Type
 ///
-/// Source: <https://www.iana.org/assignments/oauth-parameters/endpoint.csv>
+/// Source: <http://www.iana.org/assignments/oauth-parameters/endpoint.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 pub enum OAuthAuthorizationEndpointResponseType {
     /// `code`
@@ -287,7 +287,7 @@ impl schemars::JsonSchema for OAuthAuthorizationEndpointResponseType {
 
 /// OAuth Token Type Hint
 ///
-/// Source: <https://www.iana.org/assignments/oauth-parameters/token-type-hint.csv>
+/// Source: <http://www.iana.org/assignments/oauth-parameters/token-type-hint.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum OAuthTokenTypeHint {
@@ -396,7 +396,7 @@ impl schemars::JsonSchema for OAuthTokenTypeHint {
 
 /// OAuth Token Endpoint Authentication Method
 ///
-/// Source: <https://www.iana.org/assignments/oauth-parameters/token-endpoint-auth-method.csv>
+/// Source: <http://www.iana.org/assignments/oauth-parameters/token-endpoint-auth-method.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum OAuthClientAuthenticationMethod {
@@ -549,7 +549,7 @@ impl schemars::JsonSchema for OAuthClientAuthenticationMethod {
 
 /// PKCE Code Challenge Method
 ///
-/// Source: <https://www.iana.org/assignments/oauth-parameters/pkce-code-challenge-method.csv>
+/// Source: <http://www.iana.org/assignments/oauth-parameters/pkce-code-challenge-method.csv>
 #[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
 #[non_exhaustive]
 pub enum PkceCodeChallengeMethod {