diff --git a/include/bitcoin/system/allocator.hpp b/include/bitcoin/system/allocator.hpp
index 7bba9fd8cc..1b7f04a4a0 100644
--- a/include/bitcoin/system/allocator.hpp
+++ b/include/bitcoin/system/allocator.hpp
@@ -281,6 +281,26 @@ inline bool operator==(const allocator<Left>& left,
 
 using byte_allocator = allocator<uint8_t>;
 
+#define CREATE(Type, allocate, ...) \
+    allocate.new_object<Type>(__VA_ARGS__), allocate.deleter<Type>(), allocate
+#define POINTER(Type, allocate, ptr) \
+    ptr, allocate.deleter<Type>(), allocate
+#define INPLACE(ptr, Type, allocate, ...) \
+    allocate.construct<std::shared_ptr<const Type>>(ptr, __VA_ARGS__, \
+        allocate.deleter<Type>(), allocate)
+
+// TODO: replace above macros with parameter pack expansion.
+////template <typename Type, typename Allocator, typename... Args>
+////auto shared_ptr(Allocator allocator, Args&&... args) NOEXCEPT
+////{
+////    return std::make_tuple
+////    (
+////        allocator.new_object<Type>(std::forward<Args>(args)...),
+////        allocator.deleter<Type>(),
+////        allocator
+////    );
+////}
+
 } // namespace libbitcoin
 
 #endif
diff --git a/src/chain/block.cpp b/src/chain/block.cpp
index 448af5f01a..33d5d84319 100644
--- a/src/chain/block.cpp
+++ b/src/chain/block.cpp
@@ -50,7 +50,7 @@ BC_PUSH_WARNING(NO_UNGUARDED_POINTERS)
 // ----------------------------------------------------------------------------
 
 block::block() NOEXCEPT
-  : block(to_shared<chain::header>(), to_shared<chain::transaction_cptrs>(),
+  : block(to_shared<chain::header>(), to_shared<transaction_cptrs>(),
       false)
 {
 }
@@ -67,7 +67,7 @@ block::block(const chain::header& header,
 }
 
 block::block(const chain::header::cptr& header,
-    const chain::transactions_cptr& txs) NOEXCEPT
+    const transactions_cptr& txs) NOEXCEPT
   : block(header ? header : to_shared<chain::header>(),
       txs ? txs : to_shared<transaction_cptrs>(), true)
 {
@@ -104,17 +104,15 @@ block::block(reader&& source, bool witness) NOEXCEPT
 }
 
 block::block(reader& source, bool witness) NOEXCEPT
-  : header_(source.get_allocator().new_object<chain::header>(source),
-        source.get_allocator().deleter<chain::header>()),
-    txs_(source.get_allocator().new_object<transaction_cptrs>(),
-        source.get_allocator().deleter<transaction_cptrs>())
+  : header_(CREATE(chain::header, source.get_allocator(), source)),
+    txs_(CREATE(transaction_cptrs, source.get_allocator()))
 {
     assign_data(source, witness);
 }
 
 // protected
 block::block(const chain::header::cptr& header,
-    const chain::transactions_cptr& txs, bool valid) NOEXCEPT
+    const transactions_cptr& txs, bool valid) NOEXCEPT
   : header_(header),
     txs_(txs),
     valid_(valid),
@@ -148,8 +146,7 @@ void block::assign_data(reader& source, bool witness) NOEXCEPT
     txs->reserve(count);
 
     for (size_t tx = 0; tx < count; ++tx)
-        txs->emplace_back(allocator.new_object<transaction>(source, witness),
-            allocator.deleter<transaction>());
+        txs->emplace_back(CREATE(transaction, allocator, source, witness));
 
     size_ = serialized_size(*txs_);
     valid_ = source;
diff --git a/src/chain/input.cpp b/src/chain/input.cpp
index 776f86d514..3ce4f4c45a 100644
--- a/src/chain/input.cpp
+++ b/src/chain/input.cpp
@@ -176,11 +176,9 @@ input::input(reader&& source) NOEXCEPT
 
 // Witness is deserialized and assigned by transaction.
 input::input(reader& source) NOEXCEPT
-  : point_(source.get_allocator().new_object<chain::point>(source),
-        source.get_allocator().deleter<chain::point>()),
-    script_(source.get_allocator().new_object<chain::script>(source, true),
-        source.get_allocator().deleter<chain::script>()),
-    witness_(nullptr),
+  : point_(CREATE(chain::point, source.get_allocator(), source)),
+    script_(CREATE(chain::script, source.get_allocator(), source, true)),
+    witness_(CREATE(chain::witness, source.get_allocator())),
     sequence_(source.read_4_bytes_little_endian()),
     valid_(source),
     size_(serialized_size(*script_))
@@ -303,10 +301,7 @@ size_t input::witnessed_size() const NOEXCEPT
 void input::set_witness(reader& source) NOEXCEPT
 {
     auto& allocator = source.get_allocator();
-
-    witness_.reset(allocator.new_object<chain::witness>(source, true),
-        allocator.deleter<chain::witness>());
-
+    witness_.reset(CREATE(chain::witness, allocator, source, true));
     size_.witnessed = ceilinged_add(size_.nominal,
         witness_->serialized_size(true));
 }
diff --git a/src/chain/operation.cpp b/src/chain/operation.cpp
index 37ed26226b..6aafff8bf3 100644
--- a/src/chain/operation.cpp
+++ b/src/chain/operation.cpp
@@ -198,7 +198,7 @@ void operation::assign_data(reader& source) NOEXCEPT
     // Guard against resetting a previously-invalid stream.
     if (!source)
     {
-        allocator.construct<chunk_cptr>(&data_, nullptr);
+        INPLACE(&data_, data_chunk, allocator, nullptr);
         return;
     }
 
@@ -221,9 +221,7 @@ void operation::assign_data(reader& source) NOEXCEPT
         source.invalidate();
 
     // An invalid source.read_bytes_raw returns nullptr.
-    allocator.construct<chunk_cptr>(&data_, source.read_bytes_raw(size),
-        allocator.deleter<data_chunk>());
-
+    INPLACE(&data_, data_chunk, allocator, source.read_bytes_raw(size));
     underflow_ = !source;
 
     // This requires that provided stream terminates at the end of the script.
@@ -236,7 +234,7 @@ void operation::assign_data(reader& source) NOEXCEPT
     {
         code_ = any_invalid;
         source.set_position(start);
-        data_ = to_shared(source.read_bytes());
+        data_.reset(POINTER(data_chunk, allocator, source.read_bytes_raw()));
     }
 
     // All byte vectors are deserializable, stream indicates own failure.
diff --git a/src/chain/output.cpp b/src/chain/output.cpp
index acc46612b9..dcbef57b89 100644
--- a/src/chain/output.cpp
+++ b/src/chain/output.cpp
@@ -92,8 +92,7 @@ output::output(reader&& source) NOEXCEPT
 
 output::output(reader& source) NOEXCEPT
   : value_(source.read_8_bytes_little_endian()),
-    script_(source.get_allocator().new_object<chain::script>(source, true),
-        source.get_allocator().deleter<chain::script>()),
+    script_(CREATE(chain::script, source.get_allocator(), source, true)),
     valid_(source),
     size_(serialized_size(*script_, value_))
 {
diff --git a/src/chain/transaction.cpp b/src/chain/transaction.cpp
index 5b0051cc22..c270817f12 100644
--- a/src/chain/transaction.cpp
+++ b/src/chain/transaction.cpp
@@ -131,10 +131,8 @@ transaction::transaction(reader&& source, bool witness) NOEXCEPT
 
 transaction::transaction(reader& source, bool witness) NOEXCEPT
   : version_(source.read_4_bytes_little_endian()),
-    inputs_(source.get_allocator().new_object<input_cptrs>(),
-        source.get_allocator().deleter<input_cptrs>()),
-    outputs_(source.get_allocator().new_object<output_cptrs>(),
-        source.get_allocator().deleter<output_cptrs>())
+    inputs_(CREATE(input_cptrs, source.get_allocator())),
+    outputs_(CREATE(output_cptrs, source.get_allocator()))
 {
     assign_data(source, witness);
 }
@@ -184,9 +182,7 @@ void transaction::assign_data(reader& source, bool witness) NOEXCEPT
     auto count = source.read_size(max_block_size);
     ins->reserve(count);
     for (size_t in = 0; in < count; ++in)
-        ins->emplace_back(
-            allocator.new_object<input>(source),
-            allocator.deleter<input>());
+        ins->emplace_back(CREATE(input, allocator, source));
 
     // Expensive repeated recomputation, so cache segregated state.
     // Detect witness as no inputs (marker) and expected flag (bip144).
@@ -202,15 +198,13 @@ void transaction::assign_data(reader& source, bool witness) NOEXCEPT
         count = source.read_size(max_block_size);
         ins->reserve(count);
         for (size_t in = 0; in < count; ++in)
-            ins->emplace_back(allocator.new_object<input>(source),
-                allocator.deleter<input>());
+            ins->emplace_back(CREATE(input, allocator, source));
 
         auto outs = to_non_const_raw_ptr(outputs_);
         count = source.read_size(max_block_size);
         outs->reserve(count);
         for (size_t out = 0; out < count; ++out)
-            outs->emplace_back(allocator.new_object<output>(source),
-                allocator.deleter<output>());
+            outs->emplace_back(CREATE(output, allocator, source));
 
         // Read or skip witnesses as specified.
         if (witness)
@@ -231,8 +225,7 @@ void transaction::assign_data(reader& source, bool witness) NOEXCEPT
         count = source.read_size(max_block_size);
         outs->reserve(count);
         for (size_t out = 0; out < count; ++out)
-            outs->emplace_back(allocator.new_object<output>(source),
-                allocator.deleter<output>());
+            outs->emplace_back(CREATE(output, allocator, source));
     }
 
     locktime_ = source.read_4_bytes_little_endian();
diff --git a/src/chain/witness.cpp b/src/chain/witness.cpp
index cfc5e09709..4da79e800c 100644
--- a/src/chain/witness.cpp
+++ b/src/chain/witness.cpp
@@ -177,8 +177,8 @@ void witness::assign_data(reader& source, bool prefix) NOEXCEPT
         for (size_t element = 0; element < count; ++element)
         {
             const auto size = source.read_size(max_block_weight);
-            stack_.emplace_back(source.read_bytes_raw(size),
-                allocator.deleter<data_chunk>());
+            stack_.emplace_back(POINTER(data_chunk, allocator,
+                source.read_bytes_raw(size)));
             size_ = element_size(size_, stack_.back());
         }
     }
@@ -187,8 +187,8 @@ void witness::assign_data(reader& source, bool prefix) NOEXCEPT
         while (!source.is_exhausted())
         {
             const auto size = source.read_size(max_block_weight);
-            stack_.emplace_back(source.read_bytes_raw(size),
-                allocator.deleter<data_chunk>());
+            stack_.emplace_back(POINTER(data_chunk, allocator,
+                source.read_bytes_raw(size)));
             size_ = element_size(size_, stack_.back());
         }
     }