diff --git a/Cargo.toml b/Cargo.toml
index 1761da5e..95ae3e9c 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "headers-accept-encoding"
-version = "1.0.1" # don't forget to update html_root_url
+version = "1.1.0" # don't forget to update html_root_url
 description = "Hypper typed HTTP headers with Accept-Encoding + zstd support"
 license = "MIT"
 readme = "README.md"
@@ -9,18 +9,13 @@ repository = "https://github.com/static-web-server/headers-accept-encoding"
 authors = ["Sean McArthur <sean@seanmonstar.com>", "Jose Quintana <joseluisq.net>"]
 keywords = ["http", "headers", "hyper", "hyperium"]
 categories = ["web-programming"]
-rust-version = "1.56"
 
-[workspace]
-members = [
-    "./",
-    "headers-core",
-]
+rust-version = "1.56"
 
 [dependencies]
-http = "0.2.0"
-headers-core = { version = "0.2" }
-base64 = "0.21.3"
+http = "1.0.0"
+headers-core = { version = "0.3" }
+base64 = "0.21.5"
 bytes = "1"
 mime = "0.3.14"
 sha1 = "0.10"
diff --git a/LICENSE b/LICENSE
index aa33b8e7..985a757d 100644
--- a/LICENSE
+++ b/LICENSE
@@ -1,4 +1,4 @@
-Copyright (c) 2014-2019 Sean McArthur
+Copyright (c) 2014-2023 Sean McArthur
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/headers-core/Cargo.toml b/headers-core/Cargo.toml
index 22c011f1..60ecec29 100644
--- a/headers-core/Cargo.toml
+++ b/headers-core/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name = "headers-core"
-version = "0.2.0" # don't forget to update html_root_url
+version = "0.3.0" # don't forget to update html_root_url
 description = "typed HTTP headers core trait"
 license = "MIT"
 readme = "README.md"
@@ -10,4 +10,4 @@ authors = ["Sean McArthur <sean@seanmonstar.com>"]
 keywords = ["http", "headers", "hyper", "hyperium"]
 
 [dependencies]
-http = "0.2.0"
+http = "1.0.0"
diff --git a/headers-core/src/lib.rs b/headers-core/src/lib.rs
index 92e3d15e..5692b65a 100644
--- a/headers-core/src/lib.rs
+++ b/headers-core/src/lib.rs
@@ -1,7 +1,7 @@
 #![deny(missing_docs)]
 #![deny(missing_debug_implementations)]
 #![cfg_attr(test, deny(warnings))]
-#![doc(html_root_url = "https://docs.rs/headers-core/0.2.0")]
+#![doc(html_root_url = "https://docs.rs/headers-core/0.3.0")]
 
 //! # headers-core
 //!
diff --git a/src/common/authorization.rs b/src/common/authorization.rs
index e62f2fd9..bb2c35ec 100644
--- a/src/common/authorization.rs
+++ b/src/common/authorization.rs
@@ -82,9 +82,9 @@ impl<C: Credentials> ::Header for Authorization<C> {
             .next()
             .and_then(|val| {
                 let slice = val.as_bytes();
-                if slice.starts_with(C::SCHEME.as_bytes())
-                    && slice.len() > C::SCHEME.len()
+                if slice.len() > C::SCHEME.len()
                     && slice[C::SCHEME.len()] == b' '
+                    && slice[..C::SCHEME.len()].eq_ignore_ascii_case(C::SCHEME.as_bytes())
                 {
                     C::decode(val).map(Authorization)
                 } else {
@@ -151,7 +151,7 @@ impl Credentials for Basic {
 
     fn decode(value: &HeaderValue) -> Option<Self> {
         debug_assert!(
-            value.as_bytes().starts_with(b"Basic "),
+            value.as_bytes()[..Self::SCHEME.len()].eq_ignore_ascii_case(Self::SCHEME.as_bytes()),
             "HeaderValue to decode should start with \"Basic ..\", received = {:?}",
             value,
         );
@@ -186,7 +186,7 @@ pub struct Bearer(HeaderValueString);
 impl Bearer {
     /// View the token part as a `&str`.
     pub fn token(&self) -> &str {
-        &self.0.as_str()["Bearer ".len()..]
+        self.0.as_str()["Bearer ".len()..].trim_start()
     }
 }
 
@@ -195,7 +195,7 @@ impl Credentials for Bearer {
 
     fn decode(value: &HeaderValue) -> Option<Self> {
         debug_assert!(
-            value.as_bytes().starts_with(b"Bearer "),
+            value.as_bytes()[..Self::SCHEME.len()].eq_ignore_ascii_case(Self::SCHEME.as_bytes()),
             "HeaderValue to decode should start with \"Bearer ..\", received = {:?}",
             value,
         );
@@ -252,6 +252,22 @@ mod tests {
         assert_eq!(auth.0.password(), "open sesame");
     }
 
+    #[test]
+    fn basic_decode_case_insensitive() {
+        let auth: Authorization<Basic> =
+            test_decode(&["basic QWxhZGRpbjpvcGVuIHNlc2FtZQ=="]).unwrap();
+        assert_eq!(auth.0.username(), "Aladdin");
+        assert_eq!(auth.0.password(), "open sesame");
+    }
+
+    #[test]
+    fn basic_decode_extra_whitespaces() {
+        let auth: Authorization<Basic> =
+            test_decode(&["Basic  QWxhZGRpbjpvcGVuIHNlc2FtZQ=="]).unwrap();
+        assert_eq!(auth.0.username(), "Aladdin");
+        assert_eq!(auth.0.password(), "open sesame");
+    }
+
     #[test]
     fn basic_decode_no_password() {
         let auth: Authorization<Basic> = test_decode(&["Basic QWxhZGRpbjo="]).unwrap();
@@ -273,6 +289,18 @@ mod tests {
         let auth: Authorization<Bearer> = test_decode(&["Bearer fpKL54jvWmEGVoRdCNjG"]).unwrap();
         assert_eq!(auth.0.token().as_bytes(), b"fpKL54jvWmEGVoRdCNjG");
     }
+
+    #[test]
+    fn bearer_decode_case_insensitive() {
+        let auth: Authorization<Bearer> = test_decode(&["bearer fpKL54jvWmEGVoRdCNjG"]).unwrap();
+        assert_eq!(auth.0.token().as_bytes(), b"fpKL54jvWmEGVoRdCNjG");
+    }
+
+    #[test]
+    fn bearer_decode_extra_whitespaces() {
+        let auth: Authorization<Bearer> = test_decode(&["Bearer   fpKL54jvWmEGVoRdCNjG"]).unwrap();
+        assert_eq!(auth.0.token().as_bytes(), b"fpKL54jvWmEGVoRdCNjG");
+    }
 }
 
 //bench_header!(raw, Authorization<String>, { vec![b"foo bar baz".to_vec()] });
diff --git a/src/common/cache_control.rs b/src/common/cache_control.rs
index afb69249..7d5db055 100644
--- a/src/common/cache_control.rs
+++ b/src/common/cache_control.rs
@@ -59,6 +59,7 @@ impl Flags {
     const PRIVATE: Self = Self { bits: 0b001000000 };
     const PROXY_REVALIDATE: Self = Self { bits: 0b010000000 };
     const IMMUTABLE: Self = Self { bits: 0b100000000 };
+    const MUST_UNDERSTAND: Self = Self { bits: 0b1000000000 };
 
     fn empty() -> Self {
         Self { bits: 0 }
@@ -121,6 +122,10 @@ impl CacheControl {
     pub fn immutable(&self) -> bool {
         self.flags.contains(Flags::IMMUTABLE)
     }
+    /// Check if the `must_understand` directive is set.
+    pub fn must_understand(&self) -> bool {
+        self.flags.contains(Flags::MUST_UNDERSTAND)
+    }
 
     /// Get the value of the `max-age` directive if set.
     pub fn max_age(&self) -> Option<Duration> {
@@ -186,6 +191,11 @@ impl CacheControl {
         self
     }
 
+    /// Set the `must_understand` directive.
+    pub fn with_must_understand(mut self) -> Self {
+        self.flags.insert(Flags::MUST_UNDERSTAND);
+        self
+    }
     /// Set the `max-age` directive.
     pub fn with_max_age(mut self, duration: Duration) -> Self {
         self.max_age = Some(duration.into());
@@ -258,6 +268,9 @@ impl FromIterator<KnownDirective> for FromIter {
                 Directive::MustRevalidate => {
                     cc.flags.insert(Flags::MUST_REVALIDATE);
                 }
+                Directive::MustUnderstand => {
+                    cc.flags.insert(Flags::MUST_UNDERSTAND);
+                }
                 Directive::Public => {
                     cc.flags.insert(Flags::PUBLIC);
                 }
@@ -310,6 +323,7 @@ impl<'a> fmt::Display for Fmt<'a> {
             if_flag(Flags::PUBLIC, Directive::Public),
             if_flag(Flags::PRIVATE, Directive::Private),
             if_flag(Flags::IMMUTABLE, Directive::Immutable),
+            if_flag(Flags::MUST_UNDERSTAND, Directive::MustUnderstand),
             if_flag(Flags::PROXY_REVALIDATE, Directive::ProxyRevalidate),
             self.0
                 .max_age
@@ -355,6 +369,7 @@ enum Directive {
 
     // response directives
     MustRevalidate,
+    MustUnderstand,
     Public,
     Private,
     Immutable,
@@ -376,6 +391,7 @@ impl fmt::Display for Directive {
                 Directive::MinFresh(secs) => return write!(f, "min-fresh={}", secs),
 
                 Directive::MustRevalidate => "must-revalidate",
+                Directive::MustUnderstand => "must-understand",
                 Directive::Public => "public",
                 Directive::Private => "private",
                 Directive::Immutable => "immutable",
@@ -399,6 +415,7 @@ impl FromStr for KnownDirective {
             "public" => Directive::Public,
             "private" => Directive::Private,
             "immutable" => Directive::Immutable,
+            "must-understand" => Directive::MustUnderstand,
             "proxy-revalidate" => Directive::ProxyRevalidate,
             "" => return Err(()),
             _ => match s.find('=') {
@@ -472,6 +489,18 @@ mod tests {
         assert!(cc.immutable());
     }
 
+    #[test]
+    fn test_must_understand() {
+        let cc = CacheControl::new().with_must_understand();
+        let headers = test_encode(cc.clone());
+        assert_eq!(headers["cache-control"], "must-understand");
+        assert_eq!(
+            test_decode::<CacheControl>(&["must-understand"]).unwrap(),
+            cc
+        );
+        assert!(cc.must_understand());
+    }
+
     #[test]
     fn test_parse_bad_syntax() {
         assert_eq!(test_decode::<CacheControl>(&["max-age=lolz"]), None);
diff --git a/src/common/range.rs b/src/common/range.rs
index 29cc79d3..6d35936d 100644
--- a/src/common/range.rs
+++ b/src/common/range.rs
@@ -48,29 +48,52 @@ impl Range {
     /// Creates a `Range` header from bounds.
     pub fn bytes(bounds: impl RangeBounds<u64>) -> Result<Self, InvalidRange> {
         let v = match (bounds.start_bound(), bounds.end_bound()) {
-            (Bound::Unbounded, Bound::Included(end)) => format!("bytes=-{}", end),
-            (Bound::Unbounded, Bound::Excluded(&end)) => format!("bytes=-{}", end - 1),
             (Bound::Included(start), Bound::Included(end)) => format!("bytes={}-{}", start, end),
             (Bound::Included(start), Bound::Excluded(&end)) => {
                 format!("bytes={}-{}", start, end - 1)
             }
             (Bound::Included(start), Bound::Unbounded) => format!("bytes={}-", start),
+            // These do not directly translate.
+            //(Bound::Unbounded, Bound::Included(end)) => format!("bytes=-{}", end),
+            //(Bound::Unbounded, Bound::Excluded(&end)) => format!("bytes=-{}", end - 1),
             _ => return Err(InvalidRange { _inner: () }),
         };
 
         Ok(Range(::HeaderValue::from_str(&v).unwrap()))
     }
 
-    /// Iterate the range sets as a tuple of bounds.
-    pub fn iter<'a>(&'a self) -> impl Iterator<Item = (Bound<u64>, Bound<u64>)> + 'a {
+    /// Iterate the range sets as a tuple of bounds, if valid with length.
+    ///
+    /// The length of the content is passed as an argument, and all ranges
+    /// that can be satisfied will be iterated.
+    pub fn satisfiable_ranges<'a>(
+        &'a self,
+        len: u64,
+    ) -> impl Iterator<Item = (Bound<u64>, Bound<u64>)> + 'a {
         let s = self
             .0
             .to_str()
             .expect("valid string checked in Header::decode()");
 
-        s["bytes=".len()..].split(',').filter_map(|spec| {
+        s["bytes=".len()..].split(',').filter_map(move |spec| {
             let mut iter = spec.trim().splitn(2, '-');
-            Some((parse_bound(iter.next()?)?, parse_bound(iter.next()?)?))
+            let start = parse_bound(iter.next()?)?;
+            let end = parse_bound(iter.next()?)?;
+
+            // Unbounded ranges in HTTP are actually a suffix
+            // For example, `-100` means the last 100 bytes.
+            if let Bound::Unbounded = start {
+                if let Bound::Included(end) = end {
+                    if len < end {
+                        // Last N bytes is larger than available!
+                        return None;
+                    }
+                    return Some((Bound::Included(len - end), Bound::Unbounded));
+                }
+                // else fall through
+            }
+
+            Some((start, end))
         })
     }
 }
@@ -416,3 +439,17 @@ fn test_byte_range_spec_to_satisfiable_range() {
 bench_header!(bytes_multi, Range, { vec![b"bytes=1-1001,2001-3001,10001-".to_vec()]});
 bench_header!(custom_unit, Range, { vec![b"other=0-100000".to_vec()]});
 */
+
+#[test]
+fn test_to_satisfiable_range_suffix() {
+    let range = super::test_decode::<Range>(&["bytes=-100"]).unwrap();
+    let bounds = range.satisfiable_ranges(350).next().unwrap();
+    assert_eq!(bounds, (Bound::Included(250), Bound::Unbounded));
+}
+
+#[test]
+fn test_to_unsatisfiable_range_suffix() {
+    let range = super::test_decode::<Range>(&["bytes=-350"]).unwrap();
+    let bounds = range.satisfiable_ranges(100).next();
+    assert_eq!(bounds, None);
+}
diff --git a/src/lib.rs b/src/lib.rs
index 09b8e203..dc809be9 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -2,7 +2,7 @@
 #![deny(missing_debug_implementations)]
 #![cfg_attr(test, deny(warnings))]
 #![cfg_attr(all(test, feature = "nightly"), feature(test))]
-#![doc(html_root_url = "https://docs.rs/headers/0.3.9")]
+#![doc(html_root_url = "https://docs.rs/headers/0.4.0")]
 
 //! # Typed HTTP Headers
 //!