diff --git a/.github/workflows/ci.yaml b/.github/workflows/ci.yaml
index a0e817c..7cb803a 100644
--- a/.github/workflows/ci.yaml
+++ b/.github/workflows/ci.yaml
@@ -14,16 +14,21 @@ jobs:
     strategy:
       matrix:
         os: [ubuntu-latest, windows-latest, macOS-latest]
-        backend: ["h1_client,native-tls", hyper_client, curl_client]
+        backend:
+          [
+            "h1-client,h1-rustls",
+            "hyper0_14-client,hyper0_14-rustls",
+            isahc0_9-client,
+          ]
 
     steps:
-    - uses: actions/checkout@master
+      - uses: actions/checkout@master
 
-    - name: check
-      run: cargo check --all-targets --workspace --no-default-features --features '${{ matrix.backend }}'
+      - name: check
+        run: cargo check --all-targets --workspace --no-default-features --features '${{ matrix.backend }}'
 
-    - name: tests
-      run: cargo test --all-targets --workspace --no-default-features --features '${{ matrix.backend }}'
+      - name: tests
+        run: cargo test --all-targets --workspace --no-default-features --features '${{ matrix.backend }}'
 
   check_no_features:
     name: Checking without default features
@@ -38,56 +43,41 @@ jobs:
     name: Running clippy & fmt & docs
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@master
+      - uses: actions/checkout@master
 
-    - name: Install nightly toolchain
-      uses: actions-rs/toolchain@v1
-      with:
-        profile: minimal
-        toolchain: nightly
-        override: true
-        components: clippy, rustfmt
+      - name: Install nightly toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          profile: minimal
+          toolchain: nightly
+          override: true
+          components: clippy, rustfmt
 
-    - name: clippy
-      run: cargo clippy --all-targets --workspace --features=docs
+      - name: clippy
+        run: cargo clippy --all-targets --workspace --features=docs
 
-    - name: fmt
-      run: cargo fmt --all -- --check
+      - name: fmt
+        run: cargo fmt --all -- --check
 
-    - name: docs
-      run: cargo doc --no-deps --features=docs
+      - name: docs
+        run: cargo doc --no-deps --features=docs
 
   check_wasm:
     name: Check wasm targets
     runs-on: ubuntu-latest
 
     steps:
-    - uses: actions/checkout@master
-
-    - name: Install nightly with wasm32-unknown-unknown
-      uses: actions-rs/toolchain@v1
-      with:
-        toolchain: nightly
-        target: wasm32-unknown-unknown
-        override: true
-
-    - name: check
-      uses: actions-rs/cargo@v1
-      with:
-        command: check
-        args: --target wasm32-unknown-unknown --no-default-features --features "native_client,wasm_client"
-
-  check_features:
-    name: Check feature combinations
-    runs-on: ubuntu-latest
-    steps:
-    - uses: actions/checkout@master
+      - uses: actions/checkout@master
 
-    - name: Install cargo-hack
-      run: cargo install cargo-hack
+      - name: Install nightly with wasm32-unknown-unknown
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: nightly
+          target: wasm32-unknown-unknown
+          override: true
 
-    - name: Check all feature combinations works properly
-      # * `--feature-powerset` - run for the feature powerset of the package
-      # * `--no-dev-deps` - build without dev-dependencies to avoid https://github.com/rust-lang/cargo/issues/4866
-      # * `--skip docs` - skip `docs` feature
-      run: cargo hack check --feature-powerset --no-dev-deps --skip docs
+      - name: check
+        uses: actions-rs/cargo@v1
+        with:
+          command: check
+          args: --target wasm32-unknown-unknown --no-default-features --features wasm-client
diff --git a/Cargo.toml b/Cargo.toml
index 4c47488..604ef4b 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "http-client"
-version = "6.5.3"
+version = "7.0.0-alpha.1"
 license = "MIT OR Apache-2.0"
 repository = "https://github.com/http-rs/http-client"
 documentation = "https://docs.rs/http-client"
@@ -20,55 +20,66 @@ features = ["docs"]
 rustdoc-args = ["--cfg", "feature=\"docs\""]
 
 [features]
-default = ["h1_client", "native-tls"]
-docs = ["h1_client", "curl_client", "wasm_client", "hyper_client"]
+docs = ["h1-client", "isahc0_9-client", "wasm-client", "hyper0_14-client", "h1-rustls", "h1-native-tls"]
 
-h1_client = ["async-h1", "async-std", "dashmap", "deadpool", "futures"]
-native_client = ["curl_client", "wasm_client"]
-curl_client = ["isahc", "async-std"]
-wasm_client = ["js-sys", "web-sys", "wasm-bindgen", "wasm-bindgen-futures", "futures", "async-std"]
-hyper_client = ["hyper", "hyper-tls", "http-types/hyperium_http", "futures-util", "tokio"]
+h1-client = ["async-h1", "async-std", "dashmap", "deadpool", "futures"]
+native-client = ["isahc0_9-client", "wasm-client"]
+isahc0_9-client = ["isahc", "async-std"]
+wasm-client = ["js-sys", "web-sys", "wasm-bindgen", "wasm-bindgen-futures", "futures", "async-std", "send_wrapper"]
+hyper0_14-client = ["hyper0_14", "http-types/hyperium_http", "futures-util", "tokio1"]
 
-native-tls = ["async-native-tls"]
-rustls = ["async-tls", "rustls_crate"]
+h1-rustls = ["async-rustls", "rustls_crate", "webpki-roots"]
+h1-native-tls = ["async-native-tls"]
 
-unstable-config = [] # deprecated
+hyper0_14-rustls = ["hyper0_14-rustls-lib", "rustls_crate"]
+hyper0_14-native-tls = ["hyper0_14-tls-lib"]
 
 [dependencies]
-async-trait = "0.1.37"
-http-types = "2.3.0"
-log = "0.4.7"
-cfg-if = "1.0.0"
-
-# h1_client
-async-h1 = { version = "2.0.0", optional = true }
-async-std = { version = "1.6.0", default-features = false, optional = true }
-async-native-tls = { version = "0.3.1", optional = true }
+async-trait = "0.1"
+http-types = "2.3"
+log = "0.4"
+cfg-if = "1.0"
+
+# h1-client
+async-h1 = { version = "2.0", optional = true }
+async-std = { version = "1.6", default-features = false, optional = true }
 dashmap = { version = "5.3.4", optional = true }
-deadpool = { version = "0.7.0", optional = true }
-futures = { version = "0.3.8", optional = true }
+deadpool = { version = "0.7", optional = true }
+futures = { version = "0.3", optional = true }
+
+# h1-client + h1-rustls
+# async-tls = { version = "0.11", optional = true }
+async-rustls = { version = "0.3", optional = true }
+webpki-roots = { version = "0.22", optional = true }
+
+# h1-client + h1-native-tls
+async-native-tls = { version = "0.4", optional = true }
+
+# hyper0_14-client
+hyper0_14 = { package = "hyper", version = "0.14", features = ["client", "http1", "tcp", "stream"], optional = true }
+futures-util = { version = "0.3", features = ["io"], optional = true }
+tokio1 = { package = "tokio", version = "1", features = ["time"], optional = true }
+
+# hyper0_14-client + hyper0_14-rustls
+hyper0_14-rustls-lib = { package = "hyper-rustls", version = "0.23", optional = true }
 
-# h1_client_rustls
-async-tls = { version = "0.11", optional = true }
-rustls_crate = { version = "0.19", optional = true, package = "rustls" }
+# hyper0_14-client + hyper0_14-native-tls
+hyper0_14-tls-lib = { package = "hyper-tls", version = "0.5", optional = true }
 
-# hyper_client
-hyper = { version = "0.13.6", features = ["tcp"], optional = true }
-hyper-tls = { version = "0.4.3", optional = true }
-futures-util = { version = "0.3.5", features = ["io"], optional = true }
-tokio = { version = "0.2", features = ["time"], optional = true }
+# h1-rustls or hyper0_14-rustls
+rustls_crate = { package = "rustls", version = "0.20", optional = true }
 
-# curl_client
+# isahc0_9-client
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 isahc = { version = "0.9", optional = true, default-features = false, features = ["http2"]  }
 
-# wasm_client
+# wasm-client
 [target.'cfg(target_arch = "wasm32")'.dependencies]
 js-sys = { version = "0.3.25", optional = true }
 wasm-bindgen = { version = "0.2.48", optional = true }
 wasm-bindgen-futures = { version = "0.4.5", optional = true }
 futures = { version = "0.3.1", optional = true }
-send_wrapper = { version = "0.6.0", features = ["futures"] }
+send_wrapper = { version = "0.6.0", features = ["futures"], optional = true }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies.web-sys]
 version = "0.3.25"
@@ -90,14 +101,15 @@ features = [
 ]
 
 [dev-dependencies]
-async-std = { version = "1.6.0", features = ["unstable", "attributes"] }
-portpicker = "0.1.0"
-tide = { version = "0.15.0", default-features = false, features = ["h1-server"] }
-tide-rustls = { version = "0.1.4" }
-tokio = { version = "0.2.21", features = ["macros"] }
+async-std = { version = "1.6", features = ["unstable", "attributes"] }
+portpicker = "0.1"
+tide = { version = "0.16", default-features = false, features = ["h1-server"] }
+tide-rustls = { version = "0.3" }
+tokio1 = { package = "tokio", version = "1", features = ["macros", "rt-multi-thread"] }
+hyper0_14 = { package = "hyper", version = "0.14", features = ["server"] }
 serde = "1.0"
 serde_json = "1.0"
-mockito = "0.23.3"
+mockito = "0.31"
 
 [dev-dependencies.getrandom]
 version = "0.2"
diff --git a/README.md b/README.md
index fb0a0aa..d056d56 100644
--- a/README.md
+++ b/README.md
@@ -41,21 +41,37 @@
   </h3>
 </div>
 
-## Installation
+## Note on intent
 
-With [cargo add][cargo-add] installed run:
+This crate is designed to support developer-facing clients instead of being used directly.
 
-```sh
-$ cargo add http-client
-```
-
-[cargo-add]: https://github.com/killercup/cargo-edit
+If you are looking for a Rust HTTP Client library which can support multiple backend http implementations,
+consider using [Surf](https://crates.io/crates/surf), which depends on this library and provides a good developer experience.
 
 ## Safety
 
 For non-wasm clients, this crate uses ``#![deny(unsafe_code)]`` to ensure everything is implemented in
 100% Safe Rust.
 
+
+## Feature Flags
+
+This crate does not work without specifying feature flags. No features are set by default.
+
+The following client backends are supported:
+- [`async-h1`]() version 1.x, via the `h1-client` feature.
+- [`hyper`]() version 0.14.x via the `hyper0_14-client` feature.
+- libcurl through [`isahc`]() version 0.9.x via the `isahc0_9-client` feature.
+- WASM to JavaScript `fetch` via the `wasm-client` feature.
+
+Additionally TLS support can be enabled by the following options:
+- `h1-rustls` uses [`rustls`](https://crates.io/crates/rustls) for the `h1-client`.
+- `h1-native-tls` uses OpenSSL for the `h1-client` _(not recommended, no automated testing)_.
+- `hyper0_14-rustls` uses [`rustls`](https://crates.io/crates/rustls) for the `hyper0-14-client`.
+- `hyper0_14-native-tls` uses OpenSSL for the `hyper0_14-client` _(not recommended, no automated testing)_.
+- `isahc0_9-client` (implicit support).
+- `wasm-client` (implicit support).
+
 ## Contributing
 
 Want to join us? Check out our ["Contributing" guide][contributing] and take a
diff --git a/examples/print_client_debug.rs b/examples/print_client_debug.rs
index 96697e0..671ccdc 100644
--- a/examples/print_client_debug.rs
+++ b/examples/print_client_debug.rs
@@ -1,22 +1,67 @@
+#[cfg(any(
+    feature = "h1-client",
+    feature = "hyper0_14-client",
+    feature = "isahc0_9-client",
+    feature = "wasm-client"
+))]
 use http_client::HttpClient;
+#[cfg(any(
+    feature = "h1-client",
+    feature = "hyper0_14-client",
+    feature = "isahc0_9-client",
+    feature = "wasm-client"
+))]
 use http_types::{Method, Request};
 
-#[cfg(any(feature = "h1_client", feature = "docs"))]
+#[cfg(feature = "hyper0_14-client")]
+#[allow(unused_imports)]
+use tokio1 as tokio;
+
+#[cfg(any(feature = "h1-client", feature = "docs"))]
 use http_client::h1::H1Client as Client;
-#[cfg(all(feature = "hyper_client", not(feature = "docs")))]
+#[cfg(all(feature = "hyper0_14-client", not(feature = "docs")))]
 use http_client::hyper::HyperClient as Client;
-#[cfg(all(feature = "curl_client", not(feature = "docs")))]
+#[cfg(all(feature = "isahc0_9-client", not(feature = "docs")))]
 use http_client::isahc::IsahcClient as Client;
-#[cfg(all(feature = "wasm_client", not(feature = "docs")))]
+#[cfg(all(feature = "wasm-client", not(feature = "docs")))]
 use http_client::wasm::WasmClient as Client;
 
-#[async_std::main]
+#[cfg(any(
+    feature = "h1-client",
+    feature = "hyper0_14-client",
+    feature = "isahc0_9-client",
+    feature = "wasm-client"
+))]
+#[cfg_attr(
+    any(
+        feature = "h1-client",
+        feature = "isahc0_9-client",
+        feature = "wasm-client"
+    ),
+    async_std::main
+)]
+#[cfg_attr(all(feature = "hyper0_14-client", not(feature = "docs")), tokio::main)]
 async fn main() {
     let client = Client::new();
 
-    let req = Request::new(Method::Get, "http://example.org");
+    let mut args = std::env::args();
+    args.next(); // ignore binary name
+    let arg = args.next();
+    println!("{arg:?}");
+    let req = Request::new(Method::Get, arg.as_deref().unwrap_or("http://example.org"));
+
+    let response = client.send(req).await.unwrap();
+    dbg!(response);
 
-    client.send(req).await.unwrap();
+    dbg!(&client);
+}
 
-    dbg!(client);
+#[cfg(not(any(
+    feature = "h1-client",
+    feature = "hyper0_14-client",
+    feature = "isahc0_9-client",
+    feature = "wasm-client"
+)))]
+fn main() {
+    eprintln!("ERROR: A client backend must be select via `--features`: h1-client, hyper0_14-client, isahc0_9-client, wasm-client")
 }
diff --git a/src/config.rs b/src/config.rs
index 4232e69..fdd49d9 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -35,12 +35,30 @@ pub struct Config {
     /// - `wasm_client`: No effect. Web browsers do not support such an option.
     pub max_connections_per_host: usize,
     /// TLS Configuration (Rustls)
-    #[cfg_attr(feature = "docs", doc(cfg(feature = "h1_client")))]
-    #[cfg(all(feature = "h1_client", feature = "rustls"))]
+    ///
+    /// Available for the following backends:
+    /// - `h1-client` with `h1-rustls` feature.
+    /// - `hyper0_14-client` with `hyper0_14-rustls` feature.
+    ///
+    /// Not available for curl or wasm clients.
+    #[cfg_attr(
+        feature = "docs",
+        doc(cfg(any(feature = "h1-rustls", feature = "hyper0_14-rustls")))
+    )]
+    #[cfg(any(feature = "h1-rustls", feature = "hyper0_14-rustls"))]
     pub tls_config: Option<std::sync::Arc<rustls_crate::ClientConfig>>,
     /// TLS Configuration (Native TLS)
-    #[cfg_attr(feature = "docs", doc(cfg(feature = "h1_client")))]
-    #[cfg(all(feature = "h1_client", feature = "native-tls", not(feature = "rustls")))]
+    ///
+    /// Available for the following backends:
+    /// - `h1-client` with `h1-native-tls` feature.
+    ///
+    /// Not available for curl or wasm clients.
+    /// Also not available for the hyper client.
+    #[cfg_attr(feature = "docs", doc(cfg(feature = "h1-native-tls")))]
+    #[cfg(all(
+        feature = "h1-native-tls",
+        not(any(feature = "h1-rustls", feature = "hyper0_14-rustls"))
+    ))]
     pub tls_config: Option<std::sync::Arc<async_native_tls::TlsConnector>>,
 }
 
@@ -53,15 +71,19 @@ impl Debug for Config {
             .field("timeout", &self.timeout)
             .field("max_connections_per_host", &self.max_connections_per_host);
 
-        #[cfg(all(feature = "h1_client", feature = "rustls"))]
+        #[cfg(any(feature = "h1-rustls", feature = "hyper0_14-rustls"))]
         {
             if self.tls_config.is_some() {
-                dbg_struct.field("tls_config", &"Some(rustls::ClientConfig)");
+                dbg_struct.field("tls_config", &Some(format_args!("rustls::ClientConfig")));
             } else {
-                dbg_struct.field("tls_config", &"None");
+                dbg_struct.field("tls_config", &None::<()>);
             }
         }
-        #[cfg(all(feature = "h1_client", feature = "native-tls", not(feature = "rustls")))]
+        #[cfg(all(
+            feature = "h1-client",
+            feature = "h1-native-tls",
+            not(feature = "h1-rustls")
+        ))]
         {
             dbg_struct.field("tls_config", &self.tls_config);
         }
@@ -78,7 +100,11 @@ impl Config {
             tcp_no_delay: false,
             timeout: Some(Duration::from_secs(60)),
             max_connections_per_host: 50,
-            #[cfg(all(feature = "h1_client", any(feature = "rustls", feature = "native-tls")))]
+            #[cfg(any(
+                feature = "h1-rustls",
+                feature = "h1-native-tls",
+                feature = "hyper0_14-rustls",
+            ))]
             tls_config: None,
         }
     }
@@ -116,8 +142,11 @@ impl Config {
     }
 
     /// Set TLS Configuration (Rustls)
-    #[cfg_attr(feature = "docs", doc(cfg(feature = "h1_client")))]
-    #[cfg(all(feature = "h1_client", feature = "rustls"))]
+    #[cfg_attr(
+        feature = "docs",
+        doc(cfg(any(feature = "h1-rustls", feature = "hyper0_14-rustls")))
+    )]
+    #[cfg(any(feature = "h1-rustls", feature = "hyper0_14-rustls"))]
     pub fn set_tls_config(
         mut self,
         tls_config: Option<std::sync::Arc<rustls_crate::ClientConfig>>,
@@ -126,8 +155,11 @@ impl Config {
         self
     }
     /// Set TLS Configuration (Native TLS)
-    #[cfg_attr(feature = "docs", doc(cfg(feature = "h1_client")))]
-    #[cfg(all(feature = "h1_client", feature = "native-tls", not(feature = "rustls")))]
+    #[cfg_attr(feature = "docs", doc(cfg(feature = "h1-native-tls")))]
+    #[cfg(all(
+        feature = "h1-native-tls",
+        not(any(feature = "h1-rustls", feature = "hyper0_14-rustls"))
+    ))]
     pub fn set_tls_config(
         mut self,
         tls_config: Option<std::sync::Arc<async_native_tls::TlsConnector>>,
diff --git a/src/h1/mod.rs b/src/h1/mod.rs
index e44e765..adf6504 100644
--- a/src/h1/mod.rs
+++ b/src/h1/mod.rs
@@ -12,9 +12,9 @@ use deadpool::managed::Pool;
 use http_types::StatusCode;
 
 cfg_if::cfg_if! {
-    if #[cfg(feature = "rustls")] {
-        use async_tls::client::TlsStream;
-    } else if #[cfg(feature = "native-tls")] {
+    if #[cfg(feature = "h1-rustls")] {
+        use async_rustls::client::TlsStream;
+    } else if #[cfg(feature = "h1-native-tls")] {
         use async_native_tls::TlsStream;
     }
 }
@@ -24,28 +24,28 @@ use crate::Config;
 use super::{async_trait, Error, HttpClient, Request, Response};
 
 mod tcp;
-#[cfg(any(feature = "native-tls", feature = "rustls"))]
+#[cfg(any(feature = "h1-native-tls", feature = "h1-rustls"))]
 mod tls;
 
 use tcp::{TcpConnWrapper, TcpConnection};
-#[cfg(any(feature = "native-tls", feature = "rustls"))]
+#[cfg(any(feature = "h1-native-tls", feature = "h1-rustls"))]
 use tls::{TlsConnWrapper, TlsConnection};
 
 type HttpPool = DashMap<SocketAddr, Pool<TcpStream, std::io::Error>>;
-#[cfg(any(feature = "native-tls", feature = "rustls"))]
+#[cfg(any(feature = "h1-native-tls", feature = "h1-rustls"))]
 type HttpsPool = DashMap<SocketAddr, Pool<TlsStream<TcpStream>, Error>>;
 
 /// async-h1 based HTTP Client, with connection pooling ("Keep-Alive").
 pub struct H1Client {
     http_pools: HttpPool,
-    #[cfg(any(feature = "native-tls", feature = "rustls"))]
+    #[cfg(any(feature = "h1-native-tls", feature = "h1-rustls"))]
     https_pools: HttpsPool,
     config: Arc<Config>,
 }
 
 impl Debug for H1Client {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
-        let https_pools = if cfg!(any(feature = "native-tls", feature = "rustls")) {
+        let https_pools = if cfg!(any(feature = "h1-native-tls", feature = "h1-rustls")) {
             self.http_pools
                 .iter()
                 .map(|pool| {
@@ -92,33 +92,11 @@ impl H1Client {
     pub fn new() -> Self {
         Self {
             http_pools: DashMap::new(),
-            #[cfg(any(feature = "native-tls", feature = "rustls"))]
+            #[cfg(any(feature = "h1-native-tls", feature = "h1-rustls"))]
             https_pools: DashMap::new(),
             config: Arc::new(Config::default()),
         }
     }
-
-    /// Create a new instance.
-    #[deprecated(
-        since = "6.5.0",
-        note = "This function is misnamed. Prefer `Config::max_connections_per_host` instead."
-    )]
-    pub fn with_max_connections(max: usize) -> Self {
-        #[cfg(features = "h1_client")]
-        assert!(max > 0, "max_connections_per_host with h1_client must be greater than zero or it will deadlock!");
-
-        let config = Config {
-            max_connections_per_host: max,
-            ..Default::default()
-        };
-
-        Self {
-            http_pools: DashMap::new(),
-            #[cfg(any(feature = "native-tls", feature = "rustls"))]
-            https_pools: DashMap::new(),
-            config: Arc::new(config),
-        }
-    }
 }
 
 #[async_trait]
@@ -127,7 +105,7 @@ impl HttpClient for H1Client {
         req.insert_header("Connection", "keep-alive");
 
         // Insert host
-        #[cfg(any(feature = "native-tls", feature = "rustls"))]
+        #[cfg(any(feature = "h1-native-tls", feature = "h1-rustls"))]
         let host = req
             .url()
             .host_str()
@@ -135,18 +113,24 @@ impl HttpClient for H1Client {
             .to_string();
 
         let scheme = req.url().scheme();
-        if scheme != "http"
-            && (scheme != "https" || cfg!(not(any(feature = "native-tls", feature = "rustls"))))
-        {
+
+        if scheme == "https" {
+            if cfg!(not(any(feature = "h1-native-tls", feature = "h1-rustls"))) {
+                return Err(Error::from_str(
+                    StatusCode::BadRequest,
+                    "invalid url scheme `https` - requires `http-client` feature `h1-rustls` or `h1-native-tls`"
+                ));
+            }
+        } else if scheme != "http" {
             return Err(Error::from_str(
                 StatusCode::BadRequest,
-                format!("invalid url scheme '{}'", scheme),
+                format!("invalid url scheme `{scheme}`"),
             ));
         }
 
         let addrs = req.url().socket_addrs(|| match req.url().scheme() {
             "http" => Some(80),
-            #[cfg(any(feature = "native-tls", feature = "rustls"))]
+            #[cfg(any(feature = "h1-native-tls", feature = "h1-rustls"))]
             "https" => Some(443),
             _ => None,
         })?;
@@ -170,7 +154,7 @@ impl HttpClient for H1Client {
                             tcp_conn.await
                         };
                     }
-                    #[cfg(any(feature = "native-tls", feature = "rustls"))]
+                    #[cfg(any(feature = "h1-native-tls", feature = "h1-rustls"))]
                     "https" => {
                         let raw_stream = async_std::net::TcpStream::connect(addr).await?;
                         req.set_peer_addr(raw_stream.peer_addr().ok());
@@ -221,7 +205,7 @@ impl HttpClient for H1Client {
                         tcp_conn.await
                     };
                 }
-                #[cfg(any(feature = "native-tls", feature = "rustls"))]
+                #[cfg(any(feature = "h1-native-tls", feature = "h1-rustls"))]
                 "https" => {
                     let pool_ref = if let Some(pool_ref) = self.https_pools.get(&addr) {
                         pool_ref
@@ -245,8 +229,16 @@ impl HttpClient for H1Client {
                         Err(e) => return Err(Error::from_str(400, e.to_string())),
                     };
 
-                    req.set_peer_addr(stream.get_ref().peer_addr().ok());
-                    req.set_local_addr(stream.get_ref().local_addr().ok());
+                    #[cfg(feature = "h1-rustls")]
+                    {
+                        req.set_peer_addr(stream.get_ref().0.peer_addr().ok());
+                        req.set_local_addr(stream.get_ref().0.local_addr().ok());
+                    }
+                    #[cfg(all(feature = "h1-native-tls", not(feature = "h1-rustls")))]
+                    {
+                        req.set_peer_addr(stream.get_ref().peer_addr().ok());
+                        req.set_local_addr(stream.get_ref().local_addr().ok());
+                    }
 
                     let tls_conn = client::connect(TlsConnWrapper::new(stream), req);
                     return if let Some(timeout) = self.config.timeout {
@@ -269,8 +261,8 @@ impl HttpClient for H1Client {
     ///
     /// Config options may not impact existing connections.
     fn set_config(&mut self, config: Config) -> http_types::Result<()> {
-        #[cfg(features = "h1_client")]
-        assert!(config.max_connections_per_host > 0, "max_connections_per_host with h1_client must be greater than zero or it will deadlock!");
+        #[cfg(feature = "h1-client")]
+        assert!(config.max_connections_per_host > 0, "max_connections_per_host with h1-client must be greater than zero or it will deadlock!");
 
         self.config = Arc::new(config);
 
@@ -279,7 +271,7 @@ impl HttpClient for H1Client {
 
     /// Get the current configuration.
     fn config(&self) -> &Config {
-        &*self.config
+        &self.config
     }
 }
 
@@ -287,12 +279,12 @@ impl TryFrom<Config> for H1Client {
     type Error = Infallible;
 
     fn try_from(config: Config) -> Result<Self, Self::Error> {
-        #[cfg(features = "h1_client")]
-        assert!(config.max_connections_per_host > 0, "max_connections_per_host with h1_client must be greater than zero or it will deadlock!");
+        #[cfg(feature = "h1-client")]
+        assert!(config.max_connections_per_host > 0, "max_connections_per_host with h1-client must be greater than zero or it will deadlock!");
 
         Ok(Self {
             http_pools: DashMap::new(),
-            #[cfg(any(feature = "native-tls", feature = "rustls"))]
+            #[cfg(any(feature = "h1-native-tls", feature = "h1-rustls"))]
             https_pools: DashMap::new(),
             config: Arc::new(config),
         })
@@ -301,12 +293,14 @@ impl TryFrom<Config> for H1Client {
 
 #[cfg(test)]
 mod tests {
-    use super::*;
+    use std::time::Duration;
+
     use async_std::prelude::*;
     use async_std::task;
     use http_types::url::Url;
     use http_types::Result;
-    use std::time::Duration;
+
+    use super::*;
 
     fn build_test_request(url: Url) -> Request {
         let mut req = Request::new(http_types::Method::Post, url);
@@ -333,7 +327,7 @@ mod tests {
         let client = task::spawn(async move {
             task::sleep(Duration::from_millis(100)).await;
             let request =
-                build_test_request(Url::parse(&format!("http://localhost:{}/", port)).unwrap());
+                build_test_request(Url::parse(&format!("http://localhost:{port}/")).unwrap());
             let mut response: Response = H1Client::new().send(request).await?;
             assert_eq!(response.body_string().await.unwrap(), "hello");
             Ok(())
diff --git a/src/h1/tcp.rs b/src/h1/tcp.rs
index 2887bc0..1c5393b 100644
--- a/src/h1/tcp.rs
+++ b/src/h1/tcp.rs
@@ -11,7 +11,7 @@ use futures::task::{Context, Poll};
 use crate::Config;
 
 #[derive(Clone)]
-#[cfg_attr(not(feature = "rustls"), derive(std::fmt::Debug))]
+#[cfg_attr(not(feature = "h1-rustls"), derive(std::fmt::Debug))]
 pub(crate) struct TcpConnection {
     addr: SocketAddr,
     config: Arc<Config>,
diff --git a/src/h1/tls.rs b/src/h1/tls.rs
index 7d3ecf4..b8e2dda 100644
--- a/src/h1/tls.rs
+++ b/src/h1/tls.rs
@@ -9,9 +9,12 @@ use futures::io::{AsyncRead, AsyncWrite};
 use futures::task::{Context, Poll};
 
 cfg_if::cfg_if! {
-    if #[cfg(feature = "rustls")] {
-        use async_tls::client::TlsStream;
-    } else if #[cfg(feature = "native-tls")] {
+    if #[cfg(feature = "h1-rustls")] {
+        use std::convert::TryInto;
+        use std::io;
+
+        use async_rustls::client::TlsStream;
+    } else if #[cfg(feature = "h1-native-tls")] {
         use async_native_tls::TlsStream;
     }
 }
@@ -19,7 +22,7 @@ cfg_if::cfg_if! {
 use crate::{Config, Error};
 
 #[derive(Clone)]
-#[cfg_attr(not(feature = "rustls"), derive(std::fmt::Debug))]
+#[cfg_attr(not(feature = "h1-rustls"), derive(std::fmt::Debug))]
 pub(crate) struct TlsConnection {
     host: String,
     addr: SocketAddr,
@@ -84,6 +87,12 @@ impl Manager<TlsStream<TcpStream>, Error> for TlsConnection {
         let mut buf = [0; 4];
         let mut cx = Context::from_waker(futures::task::noop_waker_ref());
 
+        #[cfg(feature = "h1-rustls")]
+        conn.get_ref()
+            .0
+            .set_nodelay(self.config.tcp_no_delay)
+            .map_err(Error::from)?;
+        #[cfg(all(feature = "h1-native-tls", not(feature = "h1-rustls")))]
         conn.get_ref()
             .set_nodelay(self.config.tcp_no_delay)
             .map_err(Error::from)?;
@@ -102,28 +111,50 @@ impl Manager<TlsStream<TcpStream>, Error> for TlsConnection {
     }
 }
 
-cfg_if::cfg_if! {
-    if #[cfg(feature = "rustls")] {
-        #[allow(unused_variables)]
-        pub(crate) async fn add_tls(host: &str, stream: TcpStream, config: &Config) -> Result<TlsStream<TcpStream>, std::io::Error> {
-            let connector = if let Some(tls_config) = config.tls_config.as_ref().cloned() {
-                tls_config.into()
-            } else {
-                async_tls::TlsConnector::default()
-            };
-
-            connector.connect(host, stream).await
-        }
-    } else if #[cfg(feature = "native-tls")] {
-        #[allow(unused_variables)]
-        pub(crate) async fn add_tls(
-            host: &str,
-            stream: TcpStream,
-            config: &Config,
-        ) -> Result<TlsStream<TcpStream>, async_native_tls::Error> {
-            let connector = config.tls_config.as_ref().cloned().unwrap_or_default();
-
-            connector.connect(host, stream).await
-        }
-    }
+#[cfg(feature = "h1-rustls")]
+#[allow(unused_variables)]
+pub(crate) async fn add_tls(
+    host: &str,
+    stream: TcpStream,
+    config: &Config,
+) -> Result<TlsStream<TcpStream>, io::Error> {
+    let connector: async_rustls::TlsConnector = if let Some(tls_config) =
+        config.tls_config.as_ref().cloned()
+    {
+        tls_config.into()
+    } else {
+        let mut root_certs = rustls_crate::RootCertStore::empty();
+        root_certs.add_server_trust_anchors(webpki_roots::TLS_SERVER_ROOTS.0.iter().map(|ta| {
+            rustls_crate::OwnedTrustAnchor::from_subject_spki_name_constraints(
+                ta.subject,
+                ta.spki,
+                ta.name_constraints,
+            )
+        }));
+        let config = rustls_crate::ClientConfig::builder()
+            .with_safe_defaults()
+            .with_root_certificates(root_certs)
+            .with_no_client_auth();
+        Arc::new(config).into()
+    };
+
+    connector
+        .connect(
+            host.try_into()
+                .map_err(|e| io::Error::new(io::ErrorKind::Other, e))?,
+            stream,
+        )
+        .await
+}
+
+#[cfg(all(feature = "h1-native-tls", not(feature = "h1-rustls")))]
+#[allow(unused_variables)]
+pub(crate) async fn add_tls(
+    host: &str,
+    stream: TcpStream,
+    config: &Config,
+) -> Result<TlsStream<TcpStream>, async_native_tls::Error> {
+    let connector = config.tls_config.as_ref().cloned().unwrap_or_default();
+
+    connector.connect(host, stream).await
 }
diff --git a/src/hyper.rs b/src/hyper.rs
index 05c329b..5deba7c 100644
--- a/src/hyper.rs
+++ b/src/hyper.rs
@@ -1,4 +1,4 @@
-//! http-client implementation for reqwest
+//! http-client implementation for hyper / tokio
 
 use std::convert::{Infallible, TryFrom};
 use std::fmt::Debug;
@@ -8,9 +8,16 @@ use std::str::FromStr;
 use futures_util::stream::TryStreamExt;
 use http_types::headers::{HeaderName, HeaderValue};
 use http_types::StatusCode;
-use hyper::body::HttpBody;
-use hyper::client::connect::Connect;
-use hyper_tls::HttpsConnector;
+use hyper0_14 as hyper;
+use hyper0_14::body::HttpBody;
+use hyper0_14::client::connect::Connect;
+use hyper0_14::client::HttpConnector;
+use tokio1 as tokio;
+
+#[cfg(feature = "hyper0_14-rustls")]
+use hyper0_14_rustls_lib::HttpsConnectorBuilder;
+#[cfg(feature = "hyper0_14-native-tls")]
+use hyper0_14_tls_lib::HttpsConnector;
 
 use crate::Config;
 
@@ -39,8 +46,21 @@ pub struct HyperClient {
 impl HyperClient {
     /// Create a new client instance.
     pub fn new() -> Self {
-        let https = HttpsConnector::new();
-        let client = hyper::Client::builder().build(https);
+        #[allow(unused_mut)]
+        let mut connector = HttpConnector::new();
+        #[cfg(any(feature = "hyper0_14-rustls", feature = "hyper0_14-native-tls"))]
+        connector.enforce_http(false);
+
+        #[cfg(feature = "hyper0_14-native-tls")]
+        let connector = HttpsConnector::new_with_connector(connector);
+        #[cfg(feature = "hyper0_14-rustls")]
+        let connector = HttpsConnectorBuilder::default()
+            .with_native_roots()
+            .https_or_http()
+            .enable_http1()
+            .wrap_connector(connector);
+
+        let client = hyper::Client::builder().build(connector);
 
         Self {
             client: Box::new(client),
@@ -90,7 +110,27 @@ impl HttpClient for HyperClient {
     ///
     /// Config options may not impact existing connections.
     fn set_config(&mut self, config: Config) -> http_types::Result<()> {
-        let connector = HttpsConnector::new();
+        #[allow(unused_mut)]
+        let mut connector = HttpConnector::new();
+        #[cfg(any(feature = "hyper0_14-rustls", feature = "hyper0_14-native-tls"))]
+        connector.enforce_http(false);
+
+        #[cfg(feature = "hyper0_14-native-tls")]
+        let connector = HttpsConnector::new_with_connector(connector);
+        #[cfg(feature = "hyper0_14-rustls")]
+        let connector = match config.tls_config {
+            Some(ref config) => HttpsConnectorBuilder::default()
+                .with_tls_config(config.as_ref().clone())
+                .https_or_http()
+                .enable_http1()
+                .wrap_connector(connector),
+            None => HttpsConnectorBuilder::default()
+                .with_native_roots()
+                .https_or_http()
+                .enable_http1()
+                .wrap_connector(connector),
+        };
+
         let mut builder = hyper::Client::builder();
 
         if !config.http_keep_alive {
@@ -113,7 +153,27 @@ impl TryFrom<Config> for HyperClient {
     type Error = Infallible;
 
     fn try_from(config: Config) -> Result<Self, Self::Error> {
-        let connector = HttpsConnector::new();
+        #[allow(unused_mut)]
+        let mut connector = HttpConnector::new();
+        #[cfg(any(feature = "hyper0_14-rustls", feature = "hyper0_14-native-tls"))]
+        connector.enforce_http(false);
+
+        #[cfg(feature = "hyper0_14-native-tls")]
+        let connector = HttpsConnector::new_with_connector(connector);
+        #[cfg(feature = "hyper0_14-rustls")]
+        let connector = match config.tls_config {
+            Some(ref config) => HttpsConnectorBuilder::default()
+                .with_tls_config(config.as_ref().clone())
+                .https_or_http()
+                .enable_http1()
+                .wrap_connector(connector),
+            None => HttpsConnectorBuilder::default()
+                .with_native_roots()
+                .https_or_http()
+                .enable_http1()
+                .wrap_connector(connector),
+        };
+
         let mut builder = hyper::Client::builder();
 
         if !config.http_keep_alive {
@@ -136,8 +196,29 @@ impl HyperHttpRequest {
 
         // `HyperClient` depends on the scheme being either "http" or "https"
         match uri.scheme_str() {
+            #[cfg(not(any(feature = "hyper0_14-rustls", feature = "hyper0_14-native-tls")))]
+            Some("http") => (),
+            #[cfg(not(any(feature = "hyper0_14-rustls", feature = "hyper0_14-native-tls")))]
+            Some("https") => {
+                return Err(Error::from_str(
+                    StatusCode::BadRequest,
+                    "invalid url scheme `https` - requires `http-client` feature `hyper0_14-rustls` or `hyper0_14-native-tls`",
+                ))
+            },
+            #[cfg(any(feature = "hyper0_14-rustls", feature = "hyper0_14-native-tls"))]
             Some("http") | Some("https") => (),
-            _ => return Err(Error::from_str(StatusCode::BadRequest, "invalid scheme")),
+            Some(scheme) => {
+                return Err(Error::from_str(
+                    StatusCode::BadRequest,
+                    format!("invalid url scheme `{scheme}`"),
+                ))
+            }
+            None => {
+                return Err(Error::from_str(
+                    StatusCode::BadRequest,
+                    "missing url scheme",
+                ))
+            }
         };
 
         let mut request = hyper::Request::builder();
@@ -180,7 +261,9 @@ impl HttpTypesResponse {
         let (parts, body) = value.into_parts();
 
         let size_hint = body.size_hint().upper().map(|s| s as usize);
-        let body = body.map_err(|err| io::Error::new(io::ErrorKind::Other, err.to_string()));
+        let body = TryStreamExt::map_err(body, |err| {
+            io::Error::new(io::ErrorKind::Other, err.to_string())
+        });
         let body = http_types::Body::from_reader(body.into_async_read(), size_hint);
 
         let mut res = Response::new(parts.status);
@@ -208,13 +291,17 @@ impl HttpTypesResponse {
 
 #[cfg(test)]
 mod tests {
-    use crate::{Error, HttpClient};
+    use std::time::Duration;
+
+    use hyper0_14 as hyper;
+    use tokio1 as tokio;
+
     use http_types::{Method, Request, Url};
     use hyper::service::{make_service_fn, service_fn};
-    use std::time::Duration;
     use tokio::sync::oneshot::channel;
 
     use super::HyperClient;
+    use crate::{Error, HttpClient};
 
     async fn echo(
         req: hyper::Request<hyper::Body>,
@@ -240,7 +327,7 @@ mod tests {
         req.set_body("hello");
 
         let client = async move {
-            tokio::time::delay_for(Duration::from_millis(100)).await;
+            tokio::time::sleep(Duration::from_millis(100)).await;
             let mut resp = client.send(req).await?;
             send.send(()).unwrap();
             assert_eq!(resp.body_string().await?, "hello");
diff --git a/src/isahc.rs b/src/isahc.rs
index 92b0f1a..6975b32 100644
--- a/src/isahc.rs
+++ b/src/isahc.rs
@@ -127,12 +127,14 @@ impl TryFrom<Config> for IsahcClient {
 
 #[cfg(test)]
 mod tests {
-    use super::*;
+    use std::time::Duration;
+
     use async_std::prelude::*;
     use async_std::task;
     use http_types::url::Url;
     use http_types::Result;
-    use std::time::Duration;
+
+    use super::*;
 
     fn build_test_request(url: Url) -> Request {
         let mut req = Request::new(http_types::Method::Post, url);
@@ -159,7 +161,7 @@ mod tests {
         let client = task::spawn(async move {
             task::sleep(Duration::from_millis(100)).await;
             let request =
-                build_test_request(Url::parse(&format!("http://localhost:{}/", port)).unwrap());
+                build_test_request(Url::parse(&format!("http://localhost:{port}/")).unwrap());
             let mut response: Response = IsahcClient::new().send(request).await?;
             assert_eq!(response.body_string().await.unwrap(), "hello");
             Ok(())
diff --git a/src/lib.rs b/src/lib.rs
index ba4102f..b098c58 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -6,36 +6,35 @@
 
 #![forbid(future_incompatible, rust_2018_idioms)]
 #![deny(missing_debug_implementations, nonstandard_style)]
-#![warn(missing_docs, missing_doc_code_examples, unreachable_pub)]
+#![warn(missing_docs, unreachable_pub)]
 #![cfg_attr(feature = "docs", feature(doc_cfg))]
 // Forbid `unsafe` for the native & curl features, but allow it (for now) under the WASM backend
 #![cfg_attr(
-    not(all(feature = "wasm_client", target_arch = "wasm32")),
+    not(all(feature = "wasm-client", target_arch = "wasm32")),
     forbid(unsafe_code)
 )]
 
 mod config;
 pub use config::Config;
 
-#[cfg_attr(feature = "docs", doc(cfg(feature = "curl_client")))]
-#[cfg(all(feature = "curl_client", not(target_arch = "wasm32")))]
+#[cfg_attr(feature = "docs", doc(cfg(feature = "isahc0_9-client")))]
+#[cfg(all(feature = "isahc0_9-client", not(target_arch = "wasm32")))]
 pub mod isahc;
 
-#[cfg_attr(feature = "docs", doc(cfg(feature = "wasm_client")))]
-#[cfg(all(feature = "wasm_client", target_arch = "wasm32"))]
+#[cfg_attr(feature = "docs", doc(cfg(feature = "wasm-client")))]
+#[cfg(all(feature = "wasm-client", target_arch = "wasm32"))]
 pub mod wasm;
 
-#[cfg_attr(feature = "docs", doc(cfg(feature = "native_client")))]
-#[cfg(any(feature = "curl_client", feature = "wasm_client"))]
+#[cfg_attr(feature = "docs", doc(cfg(feature = "native-client")))]
+#[cfg(any(feature = "isahc0_9-client", feature = "wasm-client"))]
 pub mod native;
 
-#[cfg_attr(feature = "docs", doc(cfg(feature = "h1_client")))]
-#[cfg_attr(feature = "docs", doc(cfg(feature = "default")))]
-#[cfg(any(feature = "h1_client", feature = "h1_client_rustls"))]
+#[cfg_attr(feature = "docs", doc(cfg(feature = "h1-client")))]
+#[cfg(feature = "h1-client")]
 pub mod h1;
 
-#[cfg_attr(feature = "docs", doc(cfg(feature = "hyper_client")))]
-#[cfg(feature = "hyper_client")]
+#[cfg_attr(feature = "docs", doc(cfg(feature = "hyper0_14-client")))]
+#[cfg(feature = "hyper0_14-client")]
 pub mod hyper;
 
 /// An HTTP Request type with a streaming body.
diff --git a/src/native.rs b/src/native.rs
index 8a0d173..3c726a1 100644
--- a/src/native.rs
+++ b/src/native.rs
@@ -1,7 +1,7 @@
 //! http-client implementation for curl + fetch
 
-#[cfg(all(feature = "curl_client", not(target_arch = "wasm32")))]
+#[cfg(all(feature = "isahc0_9-client", not(target_arch = "wasm32")))]
 pub use super::isahc::IsahcClient as NativeClient;
 
-#[cfg(all(feature = "wasm_client", target_arch = "wasm32"))]
+#[cfg(all(feature = "wasm-client", target_arch = "wasm32"))]
 pub use super::wasm::WasmClient as NativeClient;
diff --git a/src/wasm.rs b/src/wasm.rs
index 2b95ce6..f05dbb7 100644
--- a/src/wasm.rs
+++ b/src/wasm.rs
@@ -97,14 +97,14 @@ where
 }
 
 mod fetch {
+    use std::iter::{IntoIterator, Iterator};
+    use std::pin::Pin;
+
     use js_sys::{Array, ArrayBuffer, Reflect, Uint8Array};
     use wasm_bindgen::{prelude::*, JsCast};
     use wasm_bindgen_futures::JsFuture;
     use web_sys::{RequestInit, Window, WorkerGlobalScope};
 
-    use std::iter::{IntoIterator, Iterator};
-    use std::pin::Pin;
-
     use http_types::StatusCode;
 
     use crate::Error;
diff --git a/tests/test.rs b/tests/test.rs
index c813d0d..a455a32 100644
--- a/tests/test.rs
+++ b/tests/test.rs
@@ -1,26 +1,35 @@
+use cfg_if::cfg_if;
+
+cfg_if! {
+    if #[cfg(any(
+        all(feature = "h1-client", feature = "h1-rustls"),
+        all(feature = "hyper0_14-client", feature = "hyper0_14-rustls"),
+        feature = "isahc0_9-client",
+        feature = "wasm-client"
+    ))] {
+
 use mockito::mock;
 
 use http_client::HttpClient;
 use http_types::{Body, Request, Response, Url};
 
-use cfg_if::cfg_if;
-
 cfg_if! {
-    if #[cfg(not(feature = "hyper_client"))] {
-        use async_std::test as atest;
-    } else {
+    if #[cfg(feature = "hyper0_14-client")] {
+        use tokio1 as tokio;
         use tokio::test as atest;
+    } else {
+        use async_std::test as atest;
     }
 }
 
 cfg_if! {
-    if #[cfg(feature = "curl_client")] {
+    if #[cfg(feature = "isahc0_9-client")] {
         use http_client::isahc::IsahcClient as DefaultClient;
-    } else if #[cfg(feature = "wasm_client")] {
+    } else if #[cfg(feature = "wasm-client")] {
         use http_client::wasm::WasmClient as DefaultClient;
-    } else if #[cfg(any(feature = "h1_client", feature = "h1_client_rustls"))] {
+    } else if #[cfg(feature = "h1-client")] {
         use http_client::h1::H1Client as DefaultClient;
-    } else if #[cfg(feature = "hyper_client")] {
+    } else if #[cfg(feature = "hyper0_14-client")] {
         use http_client::hyper::HyperClient as DefaultClient;
     }
 }
@@ -83,7 +92,7 @@ async fn get_google() -> Result<(), http_types::Error> {
 
     let msg = res.body_bytes().await?;
     let msg = String::from_utf8_lossy(&msg);
-    println!("recieved: '{}'", msg);
+    println!("received: '{msg}'");
     assert!(msg.contains("<!doctype html>"));
     assert!(msg.contains("<title>Google</title>"));
     assert!(msg.contains("<head>"));
@@ -161,7 +170,10 @@ async fn fallback_to_ipv4() {
     // Kips the initial "http://127.0.0.1:" to get only the port number
     let mock_port = &mockito::server_url()[17..];
 
-    let url = &format!("http://localhost:{}", mock_port);
+    let url = &format!("http://localhost:{mock_port}");
     let req = Request::new(http_types::Method::Get, Url::parse(url).unwrap());
     client.send(req.clone()).await.unwrap();
 }
+
+    }
+}