diff --git a/src/span.h b/src/span.h
--- a/src/span.h
+++ b/src/span.h
@@ -5,6 +5,7 @@
 #ifndef BITCOIN_SPAN_H
 #define BITCOIN_SPAN_H
 
+#include <algorithm>
 #include <cstddef>
 #include <type_traits>
 
@@ -20,9 +21,51 @@
     constexpr Span() noexcept : m_data(nullptr), m_size(0) {}
     constexpr Span(C *data, std::ptrdiff_t size) noexcept
         : m_data(data), m_size(size) {}
+    constexpr Span(C *data, C *end) noexcept
+        : m_data(data), m_size(end - data) {}
 
     constexpr C *data() const noexcept { return m_data; }
+    constexpr C *begin() const noexcept { return m_data; }
+    constexpr C *end() const noexcept { return m_data + m_size; }
     constexpr std::ptrdiff_t size() const noexcept { return m_size; }
+    constexpr C &operator[](std::ptrdiff_t pos) const noexcept {
+        return m_data[pos];
+    }
+
+    constexpr Span<C> subspan(std::ptrdiff_t offset) const noexcept {
+        return Span<C>(m_data + offset, m_size - offset);
+    }
+    constexpr Span<C> subspan(std::ptrdiff_t offset, std::ptrdiff_t count) const
+        noexcept {
+        return Span<C>(m_data + offset, count);
+    }
+    constexpr Span<C> first(std::ptrdiff_t count) const noexcept {
+        return Span<C>(m_data, count);
+    }
+    constexpr Span<C> last(std::ptrdiff_t count) const noexcept {
+        return Span<C>(m_data + m_size - count, count);
+    }
+
+    friend constexpr bool operator==(const Span &a, const Span &b) noexcept {
+        return a.size() == b.size() &&
+               std::equal(a.begin(), a.end(), b.begin());
+    }
+    friend constexpr bool operator!=(const Span &a, const Span &b) noexcept {
+        return !(a == b);
+    }
+    friend constexpr bool operator<(const Span &a, const Span &b) noexcept {
+        return std::lexicographical_compare(a.begin(), a.end(), b.begin(),
+                                            b.end());
+    }
+    friend constexpr bool operator<=(const Span &a, const Span &b) noexcept {
+        return !(b < a);
+    }
+    friend constexpr bool operator>(const Span &a, const Span &b) noexcept {
+        return (b < a);
+    }
+    friend constexpr bool operator>=(const Span &a, const Span &b) noexcept {
+        return !(a < b);
+    }
 };
 
 /** Create a span to a container exposing data() and size().
@@ -35,6 +78,10 @@
  * std::span will have a constructor that implements this functionality
  * directly.
  */
+template <typename A, int N> constexpr Span<A> MakeSpan(A (&a)[N]) {
+    return Span<A>(a, N);
+}
+
 template <typename V>
 constexpr Span<
     typename std::remove_pointer<decltype(std::declval<V>().data())>::type>