diff --git a/include/bitlib/bit-containers/bit_array.hpp b/include/bitlib/bit-containers/bit_array.hpp
index e1eab6e9..b7c5485d 100644
--- a/include/bitlib/bit-containers/bit_array.hpp
+++ b/include/bitlib/bit-containers/bit_array.hpp
@@ -80,6 +80,7 @@ class bit_array : public bit_array_base<bit_array<T, N, V, W>, T, W, detail::bit
 
   alignas(static_cast<size_t>(V)) std::array<word_type, AlignedWords> storage;
 
+  friend class bit_array<T, std::dynamic_extent, V, W>;
  public:
   /*
   * Constructors, copies and moves...
diff --git a/include/bitlib/bit-containers/bit_span.hpp b/include/bitlib/bit-containers/bit_span.hpp
index 74c8ed2f..69690e13 100644
--- a/include/bitlib/bit-containers/bit_span.hpp
+++ b/include/bitlib/bit-containers/bit_span.hpp
@@ -13,6 +13,7 @@
 #include "bitlib/bit-algorithms/bit_algorithm.hpp"
 #include "bitlib/bit-containers/bit_bitsof.hpp"
 #include "bitlib/bit-iterator/bit.hpp"
+#include "bitlib/bit_concepts.hpp"
 
 namespace bit {
 
@@ -88,6 +89,8 @@ class bit_span : private bit_span_storage<WordType, Extent> {
   constexpr bit_span(WordType* s)
     requires(std::is_scalar_v<WordType>);
 
+  constexpr bit_span(bit_range auto& other);
+
   // --- Observers ---
 
   // Returns the number of bits in the span.
@@ -215,6 +218,16 @@ constexpr bit_span<WordType, Extent>::bit_span(WordType& word_ref)
     : bit_span(&word_ref) {
 }
 
+template <typename WordType, std::size_t Extent>
+constexpr bit_span<WordType, Extent>::bit_span(bit_range auto& other) {
+  if constexpr (Extent == std::dynamic_extent) {
+    this->size_ = other.size();
+  } else {
+    assert(other.size() == Extent);
+  }
+  this->data_ = &(*other.begin());
+}
+
 // --- Observers ---
 
 // Returns the number of bits in the span.
diff --git a/include/bitlib/bit-iterator/bit_iterator.hpp b/include/bitlib/bit-iterator/bit_iterator.hpp
index 90b4828a..a60903b3 100644
--- a/include/bitlib/bit-iterator/bit_iterator.hpp
+++ b/include/bitlib/bit-iterator/bit_iterator.hpp
@@ -69,6 +69,7 @@ class bit_iterator
  public:
   template <class T>
   constexpr bit_iterator& operator=(const bit_iterator<T>& other);
+  constexpr bit_iterator& operator=(const bit_iterator& other);
 
   // Access
  public:
@@ -167,6 +168,14 @@ constexpr bit_iterator<Iterator>& bit_iterator<Iterator>::operator=(
   assert(_position < bitsof<word_type>());
   return *this;
 }
+template <class Iterator>
+constexpr bit_iterator<Iterator>& bit_iterator<Iterator>::operator=(
+    const bit_iterator<Iterator>& other) {
+  _current = other._current;
+  _position = other._position;
+  assert(_position < bitsof<word_type>());
+  return *this;
+}
 // -------------------------------------------------------------------------- //