diff --git a/src/compile.rs b/src/compile.rs
index cdc583c..9ffd347 100644
--- a/src/compile.rs
+++ b/src/compile.rs
@@ -1,4 +1,5 @@
 use std::collections::HashMap;
+use std::fmt;
 use std::iter;
 use std::result;
 use std::sync::Arc;
@@ -25,6 +26,9 @@
 
 /// A compiler translates a regular expression AST to a sequence of
 /// instructions. The sequence of instructions represents an NFA.
+// `Compiler` is only public via the `internal` module, so avoid deriving
+// `Debug`.
+#[allow(missing_debug_implementations)]
 pub struct Compiler {
     insts: Vec<MaybeInst>,
     compiled: Program,
@@ -1051,6 +1055,7 @@
 /// This uses similar idea to [`SparseSet`](../sparse/struct.SparseSet.html),
 /// except it uses hashes as original indices and then compares full keys for
 /// validation against `dense` array.
+#[derive(Debug)]
 struct SuffixCache {
     sparse: Box<[usize]>,
     dense: Vec<SuffixCacheEntry>,
@@ -1159,6 +1164,12 @@
     }
 }
 
+impl fmt::Debug for ByteClassSet {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        f.debug_tuple("ByteClassSet").field(&&self.0[..]).finish()
+    }
+}
+
 fn u32_to_usize(n: u32) -> usize {
     // In case usize is less than 32 bits, we need to guard against overflow.
     // On most platforms this compiles to nothing.
diff --git a/src/exec.rs b/src/exec.rs
index acca2dc..e1aae87 100644
--- a/src/exec.rs
+++ b/src/exec.rs
@@ -30,6 +30,7 @@
 /// In particular, this manages the various compiled forms of a single regular
 /// expression and the choice of which matching engine to use to execute a
 /// regular expression.
+#[derive(Debug)]
 pub struct Exec {
     /// All read only state.
     ro: Arc<ExecReadOnly>,
@@ -49,6 +50,7 @@
 }
 
 /// `ExecNoSyncStr` is like `ExecNoSync`, but matches on &str instead of &[u8].
+#[derive(Debug)]
 pub struct ExecNoSyncStr<'c>(ExecNoSync<'c>);
 
 /// `ExecReadOnly` comprises all read only state for a regex. Namely, all such
@@ -97,6 +99,9 @@
 /// Facilitates the construction of an executor by exposing various knobs
 /// to control how a regex is executed and what kinds of resources it's
 /// permitted to use.
+// `ExecBuilder` is only public via the `internal` module, so avoid deriving
+// `Debug`.
+#[allow(missing_debug_implementations)]
 pub struct ExecBuilder {
     options: RegexOptions,
     match_type: Option<MatchType>,
diff --git a/src/lib.rs b/src/lib.rs
index bdcebd4..d3dc58d 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -616,6 +616,7 @@
 #![deny(missing_docs)]
 #![cfg_attr(test, deny(warnings))]
 #![cfg_attr(feature = "pattern", feature(pattern))]
+#![warn(missing_debug_implementations)]
 
 #[cfg(not(feature = "std"))]
 compile_error!("`std` feature is currently required to build this crate");
diff --git a/src/literal/imp.rs b/src/literal/imp.rs
index fe07ffc..e4d04ed 100644
--- a/src/literal/imp.rs
+++ b/src/literal/imp.rs
@@ -72,7 +72,7 @@
     /// Returns true if all matches comprise the entire regular expression.
     ///
     /// This does not necessarily mean that a literal match implies a match
-    /// of the regular expression. For example, the regular expresison `^a`
+    /// of the regular expression. For example, the regular expression `^a`
     /// is comprised of a single complete literal `a`, but the regular
     /// expression demands that it only match at the beginning of a string.
     pub fn complete(&self) -> bool {
@@ -232,6 +232,7 @@
     }
 }
 
+#[derive(Debug)]
 pub enum LiteralIter<'a> {
     Empty,
     Bytes(&'a [u8]),
diff --git a/src/re_builder.rs b/src/re_builder.rs
index 3fef99d..fc140f8 100644
--- a/src/re_builder.rs
+++ b/src/re_builder.rs
@@ -47,6 +47,7 @@
             /// A builder can be used to configure how the regex is built, for example, by
             /// setting the default flags (which can be overridden in the expression
             /// itself) or setting various limits.
+            #[derive(Debug)]
             pub struct RegexBuilder(RegexOptions);
 
             impl RegexBuilder {
@@ -244,6 +245,7 @@
             /// A builder can be used to configure how the regexes are built, for example,
             /// by setting the default flags (which can be overridden in the expression
             /// itself) or setting various limits.
+            #[derive(Debug)]
             pub struct RegexSetBuilder(RegexOptions);
 
             impl RegexSetBuilder {
diff --git a/src/re_bytes.rs b/src/re_bytes.rs
index ca01e0e..a091436 100644
--- a/src/re_bytes.rs
+++ b/src/re_bytes.rs
@@ -1,6 +1,7 @@
 use std::borrow::Cow;
 use std::collections::HashMap;
 use std::fmt;
+use std::iter::FusedIterator;
 use std::ops::{Index, Range};
 use std::str::FromStr;
 use std::sync::Arc;
@@ -690,6 +691,7 @@
 ///
 /// `'r` is the lifetime of the compiled regular expression and `'t` is the
 /// lifetime of the matched byte string.
+#[derive(Debug)]
 pub struct Matches<'r, 't>(re_trait::Matches<'t, ExecNoSync<'r>>);
 
 impl<'r, 't> Iterator for Matches<'r, 't> {
@@ -701,6 +703,8 @@
     }
 }
 
+impl<'r, 't> FusedIterator for Matches<'r, 't> {}
+
 /// An iterator that yields all non-overlapping capture groups matching a
 /// particular regular expression.
 ///
@@ -708,6 +712,7 @@
 ///
 /// `'r` is the lifetime of the compiled regular expression and `'t` is the
 /// lifetime of the matched byte string.
+#[derive(Debug)]
 pub struct CaptureMatches<'r, 't>(
     re_trait::CaptureMatches<'t, ExecNoSync<'r>>,
 );
@@ -724,10 +729,13 @@
     }
 }
 
+impl<'r, 't> FusedIterator for CaptureMatches<'r, 't> {}
+
 /// Yields all substrings delimited by a regular expression match.
 ///
 /// `'r` is the lifetime of the compiled regular expression and `'t` is the
 /// lifetime of the byte string being split.
+#[derive(Debug)]
 pub struct Split<'r, 't> {
     finder: Matches<'r, 't>,
     last: usize,
@@ -757,12 +765,15 @@
     }
 }
 
+impl<'r, 't> FusedIterator for Split<'r, 't> {}
+
 /// Yields at most `N` substrings delimited by a regular expression match.
 ///
 /// The last substring will be whatever remains after splitting.
 ///
 /// `'r` is the lifetime of the compiled regular expression and `'t` is the
 /// lifetime of the byte string being split.
+#[derive(Debug)]
 pub struct SplitN<'r, 't> {
     splits: Split<'r, 't>,
     n: usize,
@@ -790,14 +801,21 @@
             Some(&text[self.splits.last..])
         }
     }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (0, Some(self.n))
+    }
 }
 
+impl<'r, 't> FusedIterator for SplitN<'r, 't> {}
+
 /// An iterator over the names of all possible captures.
 ///
 /// `None` indicates an unnamed capture; the first element (capture 0, the
 /// whole matched region) is always unnamed.
 ///
 /// `'r` is the lifetime of the compiled regular expression.
+#[derive(Clone, Debug)]
 pub struct CaptureNames<'r>(::std::slice::Iter<'r, Option<String>>);
 
 impl<'r> Iterator for CaptureNames<'r> {
@@ -813,8 +831,16 @@
     fn size_hint(&self) -> (usize, Option<usize>) {
         self.0.size_hint()
     }
+
+    fn count(self) -> usize {
+        self.0.count()
+    }
 }
 
+impl<'r> ExactSizeIterator for CaptureNames<'r> {}
+
+impl<'r> FusedIterator for CaptureNames<'r> {}
+
 /// CaptureLocations is a low level representation of the raw offsets of each
 /// submatch.
 ///
@@ -1057,7 +1083,7 @@
 ///
 /// The lifetime `'c` corresponds to the lifetime of the `Captures` value, and
 /// the lifetime `'t` corresponds to the originally matched text.
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct SubCaptureMatches<'c, 't: 'c> {
     caps: &'c Captures<'t>,
     it: SubCapturesPosIter<'c>,
@@ -1073,6 +1099,8 @@
     }
 }
 
+impl<'c, 't> FusedIterator for SubCaptureMatches<'c, 't> {}
+
 /// Replacer describes types that can be used to replace matches in a byte
 /// string.
 ///
@@ -1173,6 +1201,7 @@
 /// and performant (since capture groups don't need to be found).
 ///
 /// `'t` is the lifetime of the literal text.
+#[derive(Clone, Debug)]
 pub struct NoExpand<'t>(pub &'t [u8]);
 
 impl<'t> Replacer for NoExpand<'t> {
diff --git a/src/re_set.rs b/src/re_set.rs
index b8954be..0a00229 100644
--- a/src/re_set.rs
+++ b/src/re_set.rs
@@ -320,6 +320,7 @@
 /// This will always produces matches in ascending order of index, where the
 /// index corresponds to the index of the regex that matched with respect to
 /// its position when initially building the set.
+#[derive(Debug)]
 pub struct SetMatchesIntoIter(iter::Enumerate<vec::IntoIter<bool>>);
 
 impl Iterator for SetMatchesIntoIter {
@@ -352,6 +353,8 @@
     }
 }
 
+impl iter::FusedIterator for SetMatchesIntoIter {}
+
 /// A borrowed iterator over the set of matches from a regex set.
 ///
 /// The lifetime `'a` refers to the lifetime of a `SetMatches` value.
@@ -359,7 +362,7 @@
 /// This will always produces matches in ascending order of index, where the
 /// index corresponds to the index of the regex that matched with respect to
 /// its position when initially building the set.
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct SetMatchesIter<'a>(iter::Enumerate<slice::Iter<'a, bool>>);
 
 impl<'a> Iterator for SetMatchesIter<'a> {
@@ -392,6 +395,8 @@
     }
 }
 
+impl<'a> iter::FusedIterator for SetMatchesIter<'a> {}
+
 #[doc(hidden)]
 impl From<Exec> for RegexSet {
     fn from(exec: Exec) -> Self {
diff --git a/src/re_trait.rs b/src/re_trait.rs
index d14a9f7..ea6be9c 100644
--- a/src/re_trait.rs
+++ b/src/re_trait.rs
@@ -1,3 +1,6 @@
+use std::fmt;
+use std::iter::FusedIterator;
+
 /// Slot is a single saved capture location. Note that there are two slots for
 /// every capture in a regular expression (one slot each for the start and end
 /// of the capture).
@@ -51,7 +54,7 @@
 /// Positions are byte indices in terms of the original string matched.
 ///
 /// `'c` is the lifetime of the captures.
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct SubCapturesPosIter<'c> {
     idx: usize,
     locs: &'c Locations,
@@ -73,6 +76,8 @@
     }
 }
 
+impl<'c> FusedIterator for SubCapturesPosIter<'c> {}
+
 /// `RegularExpression` describes types that can implement regex searching.
 ///
 /// This trait is my attempt at reducing code duplication and to standardize
@@ -85,9 +90,9 @@
 /// somewhat reasonable. One particular thing this trait would expose would be
 /// the ability to start the search of a regex anywhere in a haystack, which
 /// isn't possible in the current public API.
-pub trait RegularExpression: Sized {
+pub trait RegularExpression: Sized + fmt::Debug {
     /// The type of the haystack.
-    type Text: ?Sized;
+    type Text: ?Sized + fmt::Debug;
 
     /// The number of capture slots in the compiled regular expression. This is
     /// always two times the number of capture groups (two slots per group).
@@ -145,6 +150,7 @@
 }
 
 /// An iterator over all non-overlapping successive leftmost-first matches.
+#[derive(Debug)]
 pub struct Matches<'t, R>
 where
     R: RegularExpression,
@@ -205,8 +211,16 @@
     }
 }
 
+impl<'t, R> FusedIterator for Matches<'t, R>
+where
+    R: RegularExpression,
+    R::Text: 't + AsRef<[u8]>,
+{
+}
+
 /// An iterator over all non-overlapping successive leftmost-first matches with
 /// captures.
+#[derive(Debug)]
 pub struct CaptureMatches<'t, R>(Matches<'t, R>)
 where
     R: RegularExpression,
@@ -260,3 +274,10 @@
         Some(locs)
     }
 }
+
+impl<'t, R> FusedIterator for CaptureMatches<'t, R>
+where
+    R: RegularExpression,
+    R::Text: 't + AsRef<[u8]>,
+{
+}
diff --git a/src/re_unicode.rs b/src/re_unicode.rs
index ea95c1b..df87c34 100644
--- a/src/re_unicode.rs
+++ b/src/re_unicode.rs
@@ -1,6 +1,7 @@
 use std::borrow::Cow;
 use std::collections::HashMap;
 use std::fmt;
+use std::iter::FusedIterator;
 use std::ops::{Index, Range};
 use std::str::FromStr;
 use std::sync::Arc;
@@ -747,6 +748,7 @@
 /// whole matched region) is always unnamed.
 ///
 /// `'r` is the lifetime of the compiled regular expression.
+#[derive(Clone, Debug)]
 pub struct CaptureNames<'r>(::std::slice::Iter<'r, Option<String>>);
 
 impl<'r> Iterator for CaptureNames<'r> {
@@ -762,12 +764,21 @@
     fn size_hint(&self) -> (usize, Option<usize>) {
         self.0.size_hint()
     }
+
+    fn count(self) -> usize {
+        self.0.count()
+    }
 }
 
+impl<'r> ExactSizeIterator for CaptureNames<'r> {}
+
+impl<'r> FusedIterator for CaptureNames<'r> {}
+
 /// Yields all substrings delimited by a regular expression match.
 ///
 /// `'r` is the lifetime of the compiled regular expression and `'t` is the
 /// lifetime of the string being split.
+#[derive(Debug)]
 pub struct Split<'r, 't> {
     finder: Matches<'r, 't>,
     last: usize,
@@ -797,12 +808,15 @@
     }
 }
 
+impl<'r, 't> FusedIterator for Split<'r, 't> {}
+
 /// Yields at most `N` substrings delimited by a regular expression match.
 ///
 /// The last substring will be whatever remains after splitting.
 ///
 /// `'r` is the lifetime of the compiled regular expression and `'t` is the
 /// lifetime of the string being split.
+#[derive(Debug)]
 pub struct SplitN<'r, 't> {
     splits: Split<'r, 't>,
     n: usize,
@@ -830,8 +844,14 @@
             Some(&text[self.splits.last..])
         }
     }
+
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        (0, Some(self.n))
+    }
 }
 
+impl<'r, 't> FusedIterator for SplitN<'r, 't> {}
+
 /// CaptureLocations is a low level representation of the raw offsets of each
 /// submatch.
 ///
@@ -1059,7 +1079,7 @@
 ///
 /// The lifetime `'c` corresponds to the lifetime of the `Captures` value, and
 /// the lifetime `'t` corresponds to the originally matched text.
-#[derive(Clone)]
+#[derive(Clone, Debug)]
 pub struct SubCaptureMatches<'c, 't: 'c> {
     caps: &'c Captures<'t>,
     it: SubCapturesPosIter<'c>,
@@ -1075,6 +1095,8 @@
     }
 }
 
+impl<'c, 't> FusedIterator for SubCaptureMatches<'c, 't> {}
+
 /// An iterator that yields all non-overlapping capture groups matching a
 /// particular regular expression.
 ///
@@ -1082,6 +1104,7 @@
 ///
 /// `'r` is the lifetime of the compiled regular expression and `'t` is the
 /// lifetime of the matched string.
+#[derive(Debug)]
 pub struct CaptureMatches<'r, 't>(
     re_trait::CaptureMatches<'t, ExecNoSyncStr<'r>>,
 );
@@ -1098,6 +1121,8 @@
     }
 }
 
+impl<'r, 't> FusedIterator for CaptureMatches<'r, 't> {}
+
 /// An iterator over all non-overlapping matches for a particular string.
 ///
 /// The iterator yields a `Match` value. The iterator stops when no more
@@ -1105,6 +1130,7 @@
 ///
 /// `'r` is the lifetime of the compiled regular expression and `'t` is the
 /// lifetime of the matched string.
+#[derive(Debug)]
 pub struct Matches<'r, 't>(re_trait::Matches<'t, ExecNoSyncStr<'r>>);
 
 impl<'r, 't> Iterator for Matches<'r, 't> {
@@ -1116,6 +1142,8 @@
     }
 }
 
+impl<'r, 't> FusedIterator for Matches<'r, 't> {}
+
 /// Replacer describes types that can be used to replace matches in a string.
 ///
 /// In general, users of this crate shouldn't need to implement this trait,
@@ -1215,6 +1243,7 @@
 /// and performant (since capture groups don't need to be found).
 ///
 /// `'t` is the lifetime of the literal text.
+#[derive(Clone, Debug)]
 pub struct NoExpand<'t>(pub &'t str);
 
 impl<'t> Replacer for NoExpand<'t> {