diff --git a/build/ipc.pro b/build/ipc.pro
index a11bccc..3eb9ceb 100644
--- a/build/ipc.pro
+++ b/build/ipc.pro
@@ -17,9 +17,6 @@ HEADERS += \
     ../include/export.h \
     ../include/def.h \
     ../include/shm.h \
-    ../include/elem_def.h \
-    ../include/elem_circ.h \
-    ../include/elem_link.h \
     ../include/waiter.h \
     ../include/queue.h \
     ../include/ipc.h \
@@ -28,11 +25,15 @@ HEADERS += \
     ../include/pool_alloc.h \
     ../include/buffer.h \
     ../src/memory/detail.h \
-    ../src/memory/alloc.hpp \
-    ../src/memory/wrapper.hpp \
-    ../src/memory/resource.hpp \
+    ../src/memory/alloc.h \
+    ../src/memory/wrapper.h \
+    ../src/memory/resource.h \
     ../src/platform/detail.h \
-    ../src/platform/waiter.h
+    ../src/platform/waiter.h \
+    ../src/circ/elem_def.h \
+    ../src/circ/elem_array.h \
+    ../src/prod_cons.h \
+    ../src/policy.h
 
 SOURCES += \
     ../src/shm.cpp \
diff --git a/include/def.h b/include/def.h
index e8fae87..5466cf9 100644
--- a/include/def.h
+++ b/include/def.h
@@ -49,11 +49,6 @@ enum : std::size_t {
     data_length   = 16
 };
 
-enum class orgnz { // data structure organization
-    linked,
-    cyclic
-};
-
 enum class relat { // multiplicity of the relationship
     single,
     multi
@@ -64,10 +59,10 @@ enum class trans { // transmission
     broadcast
 };
 
-// producer-consumer policy declaration
+// producer-consumer policy flag
 
-template <orgnz Oz, relat Rp, relat Rc, trans Ts>
-struct prod_cons;
+template <relat Rp, relat Rc, trans Ts>
+struct prod_cons {};
 
 // concept helpers
 
diff --git a/include/elem_circ.h b/include/elem_circ.h
deleted file mode 100644
index cfca3ab..0000000
--- a/include/elem_circ.h
+++ /dev/null
@@ -1,323 +0,0 @@
-#pragma once
-
-#include <atomic>
-#include <thread>
-#include <cstring>
-#include <utility>
-#include <type_traits>
-
-#include "def.h"
-#include "rw_lock.h"
-#include "elem_def.h"
-
-#include "platform/waiter.h"
-
-namespace ipc {
-
-namespace circ {
-namespace detail {
-
-using u1_t = uint_t<8>;
-using u2_t = uint_t<16>;
-
-constexpr u1_t index_of(u2_t c) noexcept {
-    return static_cast<u1_t>(c);
-}
-
-struct elem_head {
-    std::atomic<std::size_t> rc_ { 0 }; // read counter
-};
-
-template <std::size_t DataSize>
-struct elem_t {
-    elem_head head_;
-    byte_t    data_[DataSize] {};
-};
-
-template <>
-struct elem_t<0> {
-    elem_head head_;
-};
-
-template <std::size_t S>
-elem_t<S>* elem_of(void* ptr) noexcept {
-    return reinterpret_cast<elem_t<S>*>(static_cast<byte_t*>(ptr) - sizeof(elem_head));
-}
-
-} // namespace detail
-} // namespace circ
-
-////////////////////////////////////////////////////////////////
-/// producer-consumer policies
-////////////////////////////////////////////////////////////////
-
-template <>
-struct prod_cons<orgnz::cyclic, relat::single, relat::single, trans::unicast> {
-    std::atomic<circ::detail::u2_t> rd_ { 0 }; // read index
-    std::atomic<circ::detail::u2_t> wt_ { 0 }; // write index
-
-#if __cplusplus >= 201703L
-    template <std::size_t DataSize>
-    constexpr static std::size_t elem_param = DataSize - sizeof(circ::detail::elem_head);
-#else /*__cplusplus < 201703L*/
-    template <std::size_t DataSize>
-    struct elem_param {
-        enum : std::size_t {
-            value = DataSize - sizeof(circ::detail::elem_head)
-        };
-    };
-#endif/*__cplusplus < 201703L*/
-
-    constexpr circ::detail::u2_t cursor() const noexcept {
-        return 0;
-    }
-
-    template <typename E, typename F, std::size_t S>
-    bool push(E* /*elems*/, F&& f, circ::detail::elem_t<S>* elem_start) {
-        auto cur_wt = circ::detail::index_of(wt_.load(std::memory_order_acquire));
-        if (cur_wt == circ::detail::index_of(rd_.load(std::memory_order_relaxed) - 1)) {
-            return false; // full
-        }
-        std::forward<F>(f)(elem_start + cur_wt);
-        wt_.fetch_add(1, std::memory_order_release);
-        return true;
-    }
-
-    template <typename E, typename F, std::size_t S>
-    bool pop(E* /*elems*/, circ::detail::u2_t& /*cur*/, F&& f, circ::detail::elem_t<S>* elem_start) noexcept {
-        auto cur_rd = circ::detail::index_of(rd_.load(std::memory_order_acquire));
-        if (cur_rd == circ::detail::index_of(wt_.load(std::memory_order_relaxed))) {
-            return false; // empty
-        }
-        std::forward<F>(f)(elem_start + cur_rd);
-        rd_.fetch_add(1, std::memory_order_release);
-        return true;
-    }
-};
-
-template <>
-struct prod_cons<orgnz::cyclic, relat::single, relat::multi , trans::unicast>
-     : prod_cons<orgnz::cyclic, relat::single, relat::single, trans::unicast> {
-
-    template <typename E, typename F, std::size_t S>
-    bool pop(E* /*elems*/, circ::detail::u2_t& /*cur*/, F&& f, circ::detail::elem_t<S>* elem_start) noexcept {
-        byte_t buff[sizeof(circ::detail::elem_t<S>)];
-        for (unsigned k = 0;;) {
-            auto cur_rd = rd_.load(std::memory_order_acquire);
-            if (circ::detail::index_of(cur_rd) ==
-                circ::detail::index_of(wt_.load(std::memory_order_relaxed))) {
-                return false; // empty
-            }
-            std::memcpy(buff, elem_start + circ::detail::index_of(cur_rd), sizeof(buff));
-            if (rd_.compare_exchange_weak(cur_rd, cur_rd + 1, std::memory_order_release)) {
-                std::forward<F>(f)(buff);
-                return true;
-            }
-            ipc::yield(k);
-        }
-    }
-};
-
-template <>
-struct prod_cons<orgnz::cyclic, relat::multi , relat::multi, trans::unicast>
-     : prod_cons<orgnz::cyclic, relat::single, relat::multi, trans::unicast> {
-
-    std::atomic<circ::detail::u2_t> ct_ { 0 }; // commit index
-
-    template <typename E, typename F, std::size_t S>
-    bool push(E* /*elems*/, F&& f, circ::detail::elem_t<S>* elem_start) {
-        circ::detail::u2_t cur_ct, nxt_ct;
-        while(1) {
-            cur_ct = ct_.load(std::memory_order_acquire);
-            if (circ::detail::index_of(nxt_ct = cur_ct + 1) ==
-                circ::detail::index_of(rd_.load(std::memory_order_relaxed))) {
-                return false; // full
-            }
-            if (ct_.compare_exchange_weak(cur_ct, nxt_ct, std::memory_order_relaxed)) {
-                break;
-            }
-            std::this_thread::yield();
-        }
-        std::forward<F>(f)(elem_start + circ::detail::index_of(cur_ct));
-        while(1) {
-            auto exp_wt = cur_ct;
-            if (wt_.compare_exchange_weak(exp_wt, nxt_ct, std::memory_order_release)) {
-                break;
-            }
-            std::this_thread::yield();
-        }
-        return true;
-    }
-};
-
-template <>
-struct prod_cons<orgnz::cyclic, relat::single, relat::multi, trans::broadcast> {
-    std::atomic<circ::detail::u2_t> wt_ { 0 }; // write index
-
-#if __cplusplus >= 201703L
-    template <std::size_t DataSize>
-    constexpr static std::size_t elem_param = DataSize;
-#else /*__cplusplus < 201703L*/
-    template <std::size_t DataSize>
-    struct elem_param { enum : std::size_t { value = DataSize }; };
-#endif/*__cplusplus < 201703L*/
-
-    /*
-        <Remarks> std::atomic<T> may not have value_type.
-        See: https://stackoverflow.com/questions/53648614/what-happened-to-stdatomicxvalue-type
-    */
-    using rc_t = decltype(circ::detail::elem_head::rc_.load());
-
-    circ::detail::u2_t cursor() const noexcept {
-        return wt_.load(std::memory_order_acquire);
-    }
-
-    template <typename E, typename F, std::size_t S>
-    bool push(E* elems, F&& f, circ::detail::elem_t<S>* elem_start) {
-        auto conn_cnt = elems->conn_count(); // acquire
-        if (conn_cnt == 0) return false;
-        auto el = elem_start + circ::detail::index_of(wt_.load(std::memory_order_relaxed));
-        // check all consumers have finished reading this element
-        while(1) {
-            rc_t expected = 0;
-            if (el->head_.rc_.compare_exchange_weak(
-                        expected, static_cast<rc_t>(conn_cnt), std::memory_order_relaxed)) {
-                break;
-            }
-            std::this_thread::yield();
-            conn_cnt = elems->conn_count(); // acquire
-            if (conn_cnt == 0) return false;
-        }
-        std::forward<F>(f)(el->data_);
-        wt_.fetch_add(1, std::memory_order_release);
-        return true;
-    }
-
-    template <typename E, typename F, std::size_t S>
-    bool pop(E* /*elems*/, circ::detail::u2_t& cur, F&& f, circ::detail::elem_t<S>* elem_start) noexcept {
-        if (cur == cursor()) return false; // acquire
-        auto el = elem_start + circ::detail::index_of(cur++);
-        std::forward<F>(f)(el->data_);
-        for (unsigned k = 0;;) {
-            rc_t cur_rc = el->head_.rc_.load(std::memory_order_acquire);
-            if (cur_rc == 0) {
-                return true;
-            }
-            if (el->head_.rc_.compare_exchange_weak(
-                        cur_rc, cur_rc - 1, std::memory_order_release)) {
-                return true;
-            }
-            ipc::yield(k);
-        }
-    }
-};
-
-template <>
-struct prod_cons<orgnz::cyclic, relat::multi , relat::multi, trans::broadcast>
-     : prod_cons<orgnz::cyclic, relat::single, relat::multi, trans::broadcast> {
-
-    std::atomic<circ::detail::u2_t> ct_ { 0 }; // commit index
-
-    template <typename E, typename F, std::size_t S>
-    bool push(E* elems, F&& f, circ::detail::elem_t<S>* elem_start) {
-        auto conn_cnt = elems->conn_count(); // acquire
-        if (conn_cnt == 0) return false;
-        circ::detail::u2_t cur_ct = ct_.fetch_add(1, std::memory_order_relaxed),
-                           nxt_ct = cur_ct + 1;
-        auto el = elem_start + circ::detail::index_of(cur_ct);
-        // check all consumers have finished reading this element
-        while(1) {
-            rc_t expected = 0;
-            if (el->head_.rc_.compare_exchange_weak(
-                        expected, static_cast<rc_t>(conn_cnt), std::memory_order_relaxed)) {
-                break;
-            }
-            std::this_thread::yield();
-            conn_cnt = elems->conn_count(); // acquire
-            if (conn_cnt == 0) return false;
-        }
-        std::forward<F>(f)(el->data_);
-        while(1) {
-            auto exp_wt = cur_ct;
-            if (wt_.compare_exchange_weak(exp_wt, nxt_ct, std::memory_order_release)) {
-                break;
-            }
-            std::this_thread::yield();
-        }
-        return true;
-    }
-};
-
-template <relat Rp, relat Rc, trans Ts>
-using prod_cons_circ = prod_cons<orgnz::cyclic, Rp, Rc, Ts>;
-
-namespace circ {
-
-////////////////////////////////////////////////////////////////
-/// element-array implementation
-////////////////////////////////////////////////////////////////
-
-template <std::size_t DataSize, typename Policy>
-class elem_array : private Policy {
-public:
-    using policy_t = Policy;
-    using base_t   = Policy;
-    using head_t   = ipc::conn_head<detail::u2_t>;
-#if __cplusplus >= 201703L
-    using elem_t   = detail::elem_t<policy_t::template elem_param<DataSize>>;
-#else /*__cplusplus < 201703L*/
-    using elem_t   = detail::elem_t<policy_t::template elem_param<DataSize>::value>;
-#endif/*__cplusplus < 201703L*/
-
-    enum : std::size_t {
-        head_size  = sizeof(policy_t) + sizeof(head_t),
-        data_size  = DataSize,
-        elem_max   = (std::numeric_limits<uint_t<8>>::max)() + 1, // default is 255 + 1
-        elem_size  = sizeof(elem_t),
-        block_size = elem_size * elem_max
-    };
-
-private:
-    head_t head_;
-    ipc::detail::waiter waiter_;
-    elem_t block_[elem_max];
-
-public:
-    elem_array() = default;
-    elem_array(const elem_array&) = delete;
-    elem_array& operator=(const elem_array&) = delete;
-
-    auto       & waiter()       { return this->waiter_; }
-    auto const & waiter() const { return this->waiter_; }
-
-    auto       & conn_waiter()       { return head_.conn_waiter(); }
-    auto const & conn_waiter() const { return head_.conn_waiter(); }
-
-    std::size_t connect   ()       noexcept { return head_.connect   (); }
-    std::size_t disconnect()       noexcept { return head_.disconnect(); }
-    std::size_t conn_count() const noexcept { return head_.conn_count(); }
-
-    using base_t::cursor;
-
-    template <typename F, typename... P>
-    bool push(F&& f) noexcept {
-        return base_t::push(this, std::forward<F>(f), block_);
-    }
-
-    template <typename F>
-    bool pop(detail::u2_t* cur, F&& f) noexcept {
-        if (cur == nullptr) return false;
-        return base_t::pop(this, *cur, std::forward<F>(f), block_);
-    }
-};
-
-template <relat Rp, relat Rc, trans Ts>
-struct prod_cons {
-    using is_fixed = std::true_type;
-
-    template <std::size_t DataSize>
-    using elems_t = elem_array<DataSize, prod_cons_circ<Rp, Rc, Ts>>;
-};
-
-} // namespace circ
-} // namespace ipc
diff --git a/include/elem_def.h b/include/elem_def.h
deleted file mode 100644
index fc51f5a..0000000
--- a/include/elem_def.h
+++ /dev/null
@@ -1,32 +0,0 @@
-#pragma once
-
-#include <atomic>
-#include <cstddef>
-#include <cstdint>
-
-#include "platform/waiter.h"
-
-namespace ipc {
-
-template <typename U2>
-struct conn_head {
-    ipc::detail::waiter cc_waiter_;
-    std::atomic<U2>     cc_ { 0 }; // connection counter
-
-    auto       & conn_waiter()       { return this->cc_waiter_; }
-    auto const & conn_waiter() const { return this->cc_waiter_; }
-
-    std::size_t connect() noexcept {
-        return cc_.fetch_add(1, std::memory_order_release);
-    }
-
-    std::size_t disconnect() noexcept {
-        return cc_.fetch_sub(1, std::memory_order_release);
-    }
-
-    std::size_t conn_count(std::memory_order order = std::memory_order_acquire) const noexcept {
-        return cc_.load(order);
-    }
-};
-
-} // namespace ipc
diff --git a/include/elem_link.h b/include/elem_link.h
deleted file mode 100644
index 9148d29..0000000
--- a/include/elem_link.h
+++ /dev/null
@@ -1,18 +0,0 @@
-#pragma once
-
-#include <atomic>
-#include <cstddef>
-#include <cstdint>
-
-#include "def.h"
-#include "rw_lock.h"
-#include "elem_def.h"
-
-namespace ipc {
-
-namespace link {
-
-
-
-} // namespace link
-} // namespace ipc
diff --git a/include/ipc.h b/include/ipc.h
index e5f1f30..af0dfae 100644
--- a/include/ipc.h
+++ b/include/ipc.h
@@ -7,14 +7,13 @@
 #include "def.h"
 #include "buffer.h"
 #include "shm.h"
-#include "elem_circ.h"
 
 namespace ipc {
 
 using handle_t = void*;
 using buff_t   = buffer;
 
-template <typename Policy>
+template <typename Flag>
 struct IPC_EXPORT channel_detail {
     static handle_t connect   (char const * name);
     static void     disconnect(handle_t h);
@@ -138,7 +137,7 @@ public:
  * (one producer/server/sender to multi consumers/clients/receivers)
 */
 using route = channel_impl<channel_detail<
-    ipc::circ::prod_cons<relat::single, relat::multi, trans::broadcast>
+    ipc::prod_cons<relat::single, relat::multi, trans::broadcast>
 >>;
 
 /*
@@ -150,7 +149,7 @@ using route = channel_impl<channel_detail<
 */
 
 using channel = channel_impl<channel_detail<
-    ipc::circ::prod_cons<relat::multi, relat::multi, trans::broadcast>
+    ipc::prod_cons<relat::multi, relat::multi, trans::broadcast>
 >>;
 
 } // namespace ipc
diff --git a/src/circ/elem_array.h b/src/circ/elem_array.h
new file mode 100644
index 0000000..e8897cd
--- /dev/null
+++ b/src/circ/elem_array.h
@@ -0,0 +1,61 @@
+#pragma once
+
+#include <atomic>
+#include <thread>
+#include <cstring>
+#include <utility>
+#include <type_traits>
+
+#include "def.h"
+#include "rw_lock.h"
+
+#include "circ/elem_def.h"
+#include "platform/detail.h"
+
+namespace ipc {
+namespace circ {
+
+////////////////////////////////////////////////////////////////
+/// element-array implementation
+////////////////////////////////////////////////////////////////
+
+template <std::size_t DataSize, typename Policy>
+class elem_array : public ipc::circ::conn_head {
+public:
+    using base_t   = ipc::circ::conn_head;
+    using policy_t = Policy;
+#if __cplusplus >= 201703L
+    using elem_t   = ipc::circ::elem_t<policy_t::template elem_param<DataSize>>;
+#else /*__cplusplus < 201703L*/
+    using elem_t   = ipc::circ::elem_t<policy_t::template elem_param<DataSize>::value>;
+#endif/*__cplusplus < 201703L*/
+
+    enum : std::size_t {
+        head_size  = sizeof(base_t) + sizeof(policy_t),
+        data_size  = DataSize,
+        elem_max   = (std::numeric_limits<uint_t<8>>::max)() + 1, // default is 255 + 1
+        elem_size  = sizeof(elem_t),
+        block_size = elem_size * elem_max
+    };
+
+private:
+    policy_t head_;
+    elem_t   block_[elem_max];
+
+public:
+    auto cursor() const noexcept { return head_.cursor(); }
+
+    template <typename F>
+    bool push(F&& f) {
+        return head_.push(this, std::forward<F>(f), block_);
+    }
+
+    template <typename F>
+    bool pop(decltype(std::declval<policy_t>().cursor())* cur, F&& f) {
+        if (cur == nullptr) return false;
+        return head_.pop(this, *cur, std::forward<F>(f), block_);
+    }
+};
+
+} // namespace circ
+} // namespace ipc
diff --git a/src/circ/elem_def.h b/src/circ/elem_def.h
new file mode 100644
index 0000000..b9ee247
--- /dev/null
+++ b/src/circ/elem_def.h
@@ -0,0 +1,68 @@
+#pragma once
+
+#include <atomic>
+#include <cstddef>
+#include <cstdint>
+
+#include "platform/waiter.h"
+
+namespace ipc {
+namespace circ {
+
+struct elem_head {
+    std::atomic<std::size_t> rc_ { 0 }; // read-counter
+};
+
+template <std::size_t DataSize>
+struct elem_t {
+    elem_head head_;
+    byte_t    data_[DataSize] {};
+};
+
+template <>
+struct elem_t<0> {
+    elem_head head_;
+};
+
+template <std::size_t S>
+elem_t<S>* elem_of(void* ptr) noexcept {
+    return reinterpret_cast<elem_t<S>*>(static_cast<byte_t*>(ptr) - sizeof(elem_head));
+}
+
+using u1_t = ipc::uint_t<8>;
+using u2_t = ipc::uint_t<16>;
+
+constexpr u1_t index_of(u2_t c) noexcept {
+    return static_cast<u1_t>(c);
+}
+
+class conn_head {
+    ipc::detail::waiter      cc_waiter_, waiter_;
+    std::atomic<std::size_t> cc_ { 0 }; // connection counter
+
+public:
+    conn_head() = default;
+    conn_head(const conn_head&) = delete;
+    conn_head& operator=(const conn_head&) = delete;
+
+    auto       & waiter()       noexcept { return this->waiter_; }
+    auto const & waiter() const noexcept { return this->waiter_; }
+
+    auto       & conn_waiter()       noexcept { return this->cc_waiter_; }
+    auto const & conn_waiter() const noexcept { return this->cc_waiter_; }
+
+    std::size_t connect() noexcept {
+        return cc_.fetch_add(1, std::memory_order_release);
+    }
+
+    std::size_t disconnect() noexcept {
+        return cc_.fetch_sub(1, std::memory_order_release);
+    }
+
+    std::size_t conn_count(std::memory_order order = std::memory_order_acquire) const noexcept {
+        return cc_.load(order);
+    }
+};
+
+} // namespace circ
+} // namespace ipc
diff --git a/src/ipc.cpp b/src/ipc.cpp
index 02db9c0..f3053fd 100644
--- a/src/ipc.cpp
+++ b/src/ipc.cpp
@@ -11,7 +11,8 @@
 #include "tls_pointer.h"
 #include "queue.h"
 
-#include "memory/resource.hpp"
+#include "policy.h"
+#include "memory/resource.h"
 
 namespace {
 
@@ -217,54 +218,57 @@ static buff_t recv(ipc::handle_t h) {
 
 }; // detail_impl<Policy>
 
+template <typename Flag>
+using policy_t = policy::choose<circ::elem_array, Flag>;
+
 } // internal-linkage
 
 namespace ipc {
 
-template <typename Policy>
-ipc::handle_t channel_detail<Policy>::connect(char const * name) {
-    return detail_impl<Policy>::connect(name);
+template <typename Flag>
+ipc::handle_t channel_detail<Flag>::connect(char const * name) {
+    return detail_impl<policy_t<Flag>>::connect(name);
 }
 
-template <typename Policy>
-void channel_detail<Policy>::disconnect(ipc::handle_t h) {
-    detail_impl<Policy>::disconnect(h);
+template <typename Flag>
+void channel_detail<Flag>::disconnect(ipc::handle_t h) {
+    detail_impl<policy_t<Flag>>::disconnect(h);
 }
 
-template <typename Policy>
-std::size_t channel_detail<Policy>::recv_count(ipc::handle_t h) {
-    return detail_impl<Policy>::recv_count(h);
+template <typename Flag>
+std::size_t channel_detail<Flag>::recv_count(ipc::handle_t h) {
+    return detail_impl<policy_t<Flag>>::recv_count(h);
 }
 
-template <typename Policy>
-bool channel_detail<Policy>::wait_for_recv(ipc::handle_t h, std::size_t r_count) {
-    return detail_impl<Policy>::wait_for_recv(h, r_count);
+template <typename Flag>
+bool channel_detail<Flag>::wait_for_recv(ipc::handle_t h, std::size_t r_count) {
+    return detail_impl<policy_t<Flag>>::wait_for_recv(h, r_count);
 }
 
-template <typename Policy>
-void channel_detail<Policy>::clear_recv(ipc::handle_t h) {
-    detail_impl<Policy>::clear_recv(h);
+template <typename Flag>
+void channel_detail<Flag>::clear_recv(ipc::handle_t h) {
+    detail_impl<policy_t<Flag>>::clear_recv(h);
 }
 
-template <typename Policy>
-void channel_detail<Policy>::clear_recv(char const * name) {
-    detail_impl<Policy>::clear_recv(name);
+template <typename Flag>
+void channel_detail<Flag>::clear_recv(char const * name) {
+    detail_impl<policy_t<Flag>>::clear_recv(name);
 }
 
-template <typename Policy>
-bool channel_detail<Policy>::send(ipc::handle_t h, void const * data, std::size_t size) {
-    return detail_impl<Policy>::send(h, data, size);
+template <typename Flag>
+bool channel_detail<Flag>::send(ipc::handle_t h, void const * data, std::size_t size) {
+    return detail_impl<policy_t<Flag>>::send(h, data, size);
 }
 
-template <typename Policy>
-buff_t channel_detail<Policy>::recv(ipc::handle_t h) {
-    return detail_impl<Policy>::recv(h);
+template <typename Flag>
+buff_t channel_detail<Flag>::recv(ipc::handle_t h) {
+    return detail_impl<policy_t<Flag>>::recv(h);
 }
 
-template struct channel_detail<ipc::circ::prod_cons<relat::single, relat::single, trans::unicast  >>;
-template struct channel_detail<ipc::circ::prod_cons<relat::single, relat::multi , trans::unicast  >>;
-template struct channel_detail<ipc::circ::prod_cons<relat::multi , relat::multi , trans::unicast  >>;
-template struct channel_detail<ipc::circ::prod_cons<relat::single, relat::multi , trans::broadcast>>;
-template struct channel_detail<ipc::circ::prod_cons<relat::multi , relat::multi , trans::broadcast>>;
+template struct channel_detail<ipc::prod_cons<relat::single, relat::single, trans::unicast  >>;
+template struct channel_detail<ipc::prod_cons<relat::single, relat::multi , trans::unicast  >>;
+template struct channel_detail<ipc::prod_cons<relat::multi , relat::multi , trans::unicast  >>;
+template struct channel_detail<ipc::prod_cons<relat::single, relat::multi , trans::broadcast>>;
+template struct channel_detail<ipc::prod_cons<relat::multi , relat::multi , trans::broadcast>>;
 
 } // namespace ipc
diff --git a/src/memory/alloc.hpp b/src/memory/alloc.h
similarity index 100%
rename from src/memory/alloc.hpp
rename to src/memory/alloc.h
diff --git a/src/memory/detail.h b/src/memory/detail.h
index c756b11..327b691 100644
--- a/src/memory/detail.h
+++ b/src/memory/detail.h
@@ -2,7 +2,7 @@
 
 #include <cstddef>
 
-#include "memory/alloc.hpp"
+#include "memory/alloc.h"
 #include "platform/detail.h"
 
 namespace ipc {
diff --git a/src/memory/resource.hpp b/src/memory/resource.h
similarity index 93%
rename from src/memory/resource.hpp
rename to src/memory/resource.h
index 554a8d0..f69d174 100644
--- a/src/memory/resource.hpp
+++ b/src/memory/resource.h
@@ -9,8 +9,8 @@
 
 #include "def.h"
 
-#include "memory/alloc.hpp"
-#include "memory/wrapper.hpp"
+#include "memory/alloc.h"
+#include "memory/wrapper.h"
 #include "memory/detail.h"
 #include "platform/detail.h"
 
diff --git a/src/memory/wrapper.hpp b/src/memory/wrapper.h
similarity index 99%
rename from src/memory/wrapper.hpp
rename to src/memory/wrapper.h
index adb1cad..c632da5 100644
--- a/src/memory/wrapper.hpp
+++ b/src/memory/wrapper.h
@@ -15,7 +15,7 @@
 #include "rw_lock.h"
 #include "tls_pointer.h"
 
-#include "memory/alloc.hpp"
+#include "memory/alloc.h"
 #include "memory/detail.h"
 #include "platform/detail.h"
 
diff --git a/src/platform/detail.h b/src/platform/detail.h
index 22296ea..760544a 100644
--- a/src/platform/detail.h
+++ b/src/platform/detail.h
@@ -4,6 +4,8 @@
 #include <mutex>
 #include <type_traits>
 
+#include "def.h"
+
 #if __cplusplus >= 201703L
 
 namespace std {
diff --git a/src/platform/shm_linux.cpp b/src/platform/shm_linux.cpp
index c41d57c..d7c435d 100644
--- a/src/platform/shm_linux.cpp
+++ b/src/platform/shm_linux.cpp
@@ -12,7 +12,7 @@
 #include <mutex>
 
 #include "def.h"
-#include "memory/resource.hpp"
+#include "memory/resource.h"
 
 namespace {
 
diff --git a/src/platform/shm_win.cpp b/src/platform/shm_win.cpp
index 3e6a671..6a7cf7c 100644
--- a/src/platform/shm_win.cpp
+++ b/src/platform/shm_win.cpp
@@ -8,7 +8,7 @@
 
 #include "def.h"
 
-#include "memory/resource.hpp"
+#include "memory/resource.h"
 #include "platform/to_tchar.h"
 
 namespace {
diff --git a/src/policy.h b/src/policy.h
new file mode 100644
index 0000000..d97bfa8
--- /dev/null
+++ b/src/policy.h
@@ -0,0 +1,25 @@
+#pragma once
+
+#include <type_traits>
+
+#include "def.h"
+#include "prod_cons.h"
+
+#include "circ/elem_array.h"
+
+namespace ipc {
+namespace policy {
+
+template <template <std::size_t, typename> class Elems, typename Flag>
+struct choose;
+
+template <typename Flag>
+struct choose<circ::elem_array, Flag> {
+    using is_fixed = std::true_type;
+
+    template <std::size_t DataSize>
+    using elems_t = circ::elem_array<DataSize, ipc::prod_cons_impl<Flag>>;
+};
+
+} // namespace policy
+} // namespace ipc
diff --git a/src/pool_alloc.cpp b/src/pool_alloc.cpp
index 5971c67..1e7faca 100644
--- a/src/pool_alloc.cpp
+++ b/src/pool_alloc.cpp
@@ -1,6 +1,6 @@
 #include "pool_alloc.h"
 
-#include "memory/resource.hpp"
+#include "memory/resource.h"
 
 namespace ipc {
 namespace mem {
diff --git a/src/prod_cons.h b/src/prod_cons.h
new file mode 100644
index 0000000..5b657de
--- /dev/null
+++ b/src/prod_cons.h
@@ -0,0 +1,218 @@
+#pragma once
+
+#include <atomic>
+#include <thread>
+#include <utility>
+#include <cstring>
+
+#include "def.h"
+
+#include "circ/elem_def.h"
+
+namespace ipc {
+
+////////////////////////////////////////////////////////////////
+/// producer-consumer implementation
+////////////////////////////////////////////////////////////////
+
+template <typename Flag>
+struct prod_cons_impl;
+
+template <>
+struct prod_cons_impl<prod_cons<relat::single, relat::single, trans::unicast>> {
+    std::atomic<circ::u2_t> rd_ { 0 }; // read index
+    std::atomic<circ::u2_t> wt_ { 0 }; // write index
+
+#if __cplusplus >= 201703L
+    template <std::size_t DataSize>
+    constexpr static std::size_t elem_param = DataSize - sizeof(circ::elem_head);
+#else /*__cplusplus < 201703L*/
+    template <std::size_t DataSize>
+    struct elem_param {
+        enum : std::size_t {
+            value = DataSize - sizeof(circ::elem_head)
+        };
+    };
+#endif/*__cplusplus < 201703L*/
+
+    constexpr circ::u2_t cursor() const noexcept {
+        return 0;
+    }
+
+    template <typename E, typename F, typename EB>
+    bool push(E* /*elems*/, F&& f, EB* elem_start) {
+        auto cur_wt = circ::index_of(wt_.load(std::memory_order_acquire));
+        if (cur_wt == circ::index_of(rd_.load(std::memory_order_relaxed) - 1)) {
+            return false; // full
+        }
+        std::forward<F>(f)(elem_start + cur_wt);
+        wt_.fetch_add(1, std::memory_order_release);
+        return true;
+    }
+
+    template <typename E, typename F, typename EB>
+    bool pop(E* /*elems*/, circ::u2_t& /*cur*/, F&& f, EB* elem_start) {
+        auto cur_rd = circ::index_of(rd_.load(std::memory_order_acquire));
+        if (cur_rd == circ::index_of(wt_.load(std::memory_order_relaxed))) {
+            return false; // empty
+        }
+        std::forward<F>(f)(elem_start + cur_rd);
+        rd_.fetch_add(1, std::memory_order_release);
+        return true;
+    }
+};
+
+template <>
+struct prod_cons_impl<prod_cons<relat::single, relat::multi , trans::unicast>>
+     : prod_cons_impl<prod_cons<relat::single, relat::single, trans::unicast>> {
+
+    template <typename E, typename F, typename EB>
+    bool pop(E* /*elems*/, circ::u2_t& /*cur*/, F&& f, EB* elem_start) {
+        byte_t buff[sizeof(E)];
+        for (unsigned k = 0;;) {
+            auto cur_rd = rd_.load(std::memory_order_acquire);
+            if (circ::index_of(cur_rd) ==
+                circ::index_of(wt_.load(std::memory_order_relaxed))) {
+                return false; // empty
+            }
+            std::memcpy(buff, elem_start + circ::index_of(cur_rd), sizeof(buff));
+            if (rd_.compare_exchange_weak(cur_rd, cur_rd + 1, std::memory_order_release)) {
+                std::forward<F>(f)(buff);
+                return true;
+            }
+            ipc::yield(k);
+        }
+    }
+};
+
+template <>
+struct prod_cons_impl<prod_cons<relat::multi , relat::multi, trans::unicast>>
+     : prod_cons_impl<prod_cons<relat::single, relat::multi, trans::unicast>> {
+
+    std::atomic<circ::u2_t> ct_ { 0 }; // commit index
+
+    template <typename E, typename F, typename EB>
+    bool push(E* /*elems*/, F&& f, EB* elem_start) {
+        circ::u2_t cur_ct, nxt_ct;
+        while(1) {
+            cur_ct = ct_.load(std::memory_order_acquire);
+            if (circ::index_of(nxt_ct = cur_ct + 1) ==
+                circ::index_of(rd_.load(std::memory_order_relaxed))) {
+                return false; // full
+            }
+            if (ct_.compare_exchange_weak(cur_ct, nxt_ct, std::memory_order_relaxed)) {
+                break;
+            }
+            std::this_thread::yield();
+        }
+        std::forward<F>(f)(elem_start + circ::index_of(cur_ct));
+        while(1) {
+            auto exp_wt = cur_ct;
+            if (wt_.compare_exchange_weak(exp_wt, nxt_ct, std::memory_order_release)) {
+                break;
+            }
+            std::this_thread::yield();
+        }
+        return true;
+    }
+};
+
+template <>
+struct prod_cons_impl<prod_cons<relat::single, relat::multi, trans::broadcast>> {
+    std::atomic<circ::u2_t> wt_ { 0 }; // write index
+
+#if __cplusplus >= 201703L
+    template <std::size_t DataSize>
+    constexpr static std::size_t elem_param = DataSize;
+#else /*__cplusplus < 201703L*/
+    template <std::size_t DataSize>
+    struct elem_param { enum : std::size_t { value = DataSize }; };
+#endif/*__cplusplus < 201703L*/
+
+    /*
+        <Remarks> std::atomic<T> may not have value_type.
+        See: https://stackoverflow.com/questions/53648614/what-happened-to-stdatomicxvalue-type
+    */
+    using rc_t = decltype(circ::elem_head::rc_.load());
+
+    circ::u2_t cursor() const noexcept {
+        return wt_.load(std::memory_order_acquire);
+    }
+
+    template <typename E, typename F, typename EB>
+    bool push(E* elems, F&& f, EB* elem_start) {
+        auto conn_cnt = elems->conn_count(); // acquire
+        if (conn_cnt == 0) return false;
+        auto el = elem_start + circ::index_of(wt_.load(std::memory_order_relaxed));
+        // check all consumers have finished reading this element
+        while(1) {
+            rc_t expected = 0;
+            if (el->head_.rc_.compare_exchange_weak(
+                        expected, static_cast<rc_t>(conn_cnt), std::memory_order_relaxed)) {
+                break;
+            }
+            std::this_thread::yield();
+            conn_cnt = elems->conn_count(); // acquire
+            if (conn_cnt == 0) return false;
+        }
+        std::forward<F>(f)(el->data_);
+        wt_.fetch_add(1, std::memory_order_release);
+        return true;
+    }
+
+    template <typename E, typename F, typename EB>
+    bool pop(E* /*elems*/, circ::u2_t& cur, F&& f, EB* elem_start) {
+        if (cur == cursor()) return false; // acquire
+        auto el = elem_start + circ::index_of(cur++);
+        std::forward<F>(f)(el->data_);
+        for (unsigned k = 0;;) {
+            rc_t cur_rc = el->head_.rc_.load(std::memory_order_acquire);
+            if (cur_rc == 0) {
+                return true;
+            }
+            if (el->head_.rc_.compare_exchange_weak(
+                        cur_rc, cur_rc - 1, std::memory_order_release)) {
+                return true;
+            }
+            ipc::yield(k);
+        }
+    }
+};
+
+template <>
+struct prod_cons_impl<prod_cons<relat::multi , relat::multi, trans::broadcast>>
+     : prod_cons_impl<prod_cons<relat::single, relat::multi, trans::broadcast>> {
+
+    std::atomic<circ::u2_t> ct_ { 0 }; // commit index
+
+    template <typename E, typename F, typename EB>
+    bool push(E* elems, F&& f, EB* elem_start) {
+        auto conn_cnt = elems->conn_count(); // acquire
+        if (conn_cnt == 0) return false;
+        circ::u2_t cur_ct = ct_.fetch_add(1, std::memory_order_relaxed),
+                   nxt_ct = cur_ct + 1;
+        auto el = elem_start + circ::index_of(cur_ct);
+        // check all consumers have finished reading this element
+        while(1) {
+            rc_t expected = 0;
+            if (el->head_.rc_.compare_exchange_weak(
+                        expected, static_cast<rc_t>(conn_cnt), std::memory_order_relaxed)) {
+                break;
+            }
+            std::this_thread::yield();
+            conn_cnt = elems->conn_count(); // acquire
+            if (conn_cnt == 0) return false;
+        }
+        std::forward<F>(f)(el->data_);
+        while(1) {
+            auto exp_wt = cur_ct;
+            if (wt_.compare_exchange_weak(exp_wt, nxt_ct, std::memory_order_release)) {
+                break;
+            }
+            std::this_thread::yield();
+        }
+        return true;
+    }
+};
+
+} // namespace ipc
diff --git a/include/queue.h b/src/queue.h
similarity index 82%
rename from include/queue.h
rename to src/queue.h
index d369df7..b0563b9 100644
--- a/include/queue.h
+++ b/src/queue.h
@@ -12,7 +12,6 @@
 
 #include "def.h"
 #include "rw_lock.h"
-#include "elem_circ.h"
 
 #include "platform/waiter.h"
 
@@ -146,6 +145,34 @@ public:
         elems_ = nullptr;
         return old;
     }
+
+    template <typename T, typename F, typename... P>
+    auto push(F&& f, P&&... params) {
+        if (elems_ == nullptr) return false;
+        if (std::forward<F>(f)([&](void* p) {
+            ::new (p) T(std::forward<P>(params)...);
+        })) {
+            this->waiter_.broadcast();
+            return true;
+        }
+        return false;
+    }
+
+    template <typename T>
+    T pop() {
+        if (elems_ == nullptr) {
+            return {};
+        }
+        T item;
+        for (unsigned k = 0;;) {
+            if (elems_->pop(&this->cursor_, [&item](void* p) {
+                ::new (&item) T(std::move(*static_cast<T*>(p)));
+            })) {
+                return item;
+            }
+            ipc::sleep(k, [this] { return this->waiter_.wait(); });
+        }
+    }
 };
 
 template <typename Elems, typename IsFixed>
@@ -159,51 +186,46 @@ public:
 
     template <typename T, typename... P>
     auto push(P&&... params) {
-        if (this->elems_ == nullptr) return false;
-        if (this->elems_->push([&](void* p) {
-            ::new (p) T(std::forward<P>(params)...);
-        })) {
-            this->waiter_.broadcast();
-            return true;
-        }
-        return false;
+        return base_t::template push<T>([this](auto&& f) {
+            return this->elems_->push(std::forward<decltype(f)>(f));
+        }, std::forward<P>(params)...);
     }
+};
 
-    template <typename T>
-    T pop() {
-        if (this->elems_ == nullptr) {
-            return {};
-        }
-        T item;
-        for (unsigned k = 0;;) {
-            if (this->elems_->pop(&this->cursor_, [&item](void* p) {
-                ::new (&item) T(std::move(*static_cast<T*>(p)));
-            })) {
-                return item;
-            }
-            ipc::sleep(k, [this] { return this->waiter_.wait(); });
-        }
+template <typename Elems>
+class queue<Elems, std::false_type> : public queue_base<Elems> {
+    using base_t = queue_base<Elems>;
+
+public:
+    using is_fixed = std::false_type;
+
+    using base_t::base_t;
+
+    template <typename T, typename... P>
+    auto push(P&&... params) {
+        return base_t::template push<T>([this](auto&& f) {
+            return this->elems_->template push<sizeof(T), alignof(T)>(std::forward<decltype(f)>(f));
+        }, std::forward<P>(params)...);
     }
 };
 
 } // namespace detail
 
-template <typename T,
-          typename Policy = ipc::circ::prod_cons<relat::single, relat::multi, trans::broadcast>>
+template <typename T, typename Policy>
 class queue : public detail::queue<typename Policy::template elems_t<sizeof(T)>, typename Policy::is_fixed> {
     using base_t = detail::queue<typename Policy::template elems_t<sizeof(T)>, typename Policy::is_fixed>;
 
 public:
     using base_t::base_t;
+    using base_t::push;
+    using base_t::pop;
 
     template <typename... P>
     auto push(P&&... params) {
         return base_t::template push<T>(std::forward<P>(params)...);
     }
 
-    T pop() {
-        return base_t::template pop<T>();
-    }
+    T pop() { return base_t::template pop<T>(); }
 };
 
 } // namespace ipc
diff --git a/test/test_circ.cpp b/test/test_circ.cpp
index 55dffa6..fa662e9 100644
--- a/test/test_circ.cpp
+++ b/test/test_circ.cpp
@@ -6,9 +6,11 @@
 #include <vector>
 #include <unordered_map>
 
-#include "elem_circ.h"
 #include "queue.h"
-#include "memory/resource.hpp"
+#include "prod_cons.h"
+#include "policy.h"
+#include "circ/elem_array.h"
+#include "memory/resource.h"
 #include "test.h"
 
 namespace {
@@ -18,10 +20,13 @@ struct msg_t {
     int dat_;
 };
 
-using cq_t = ipc::circ::elem_array<sizeof(msg_t), 
-                                   ipc::prod_cons_circ<ipc::relat::single,
-                                                       ipc::relat::multi, 
-                                                       ipc::trans::broadcast>>;
+template <ipc::relat Rp, ipc::relat Rc, ipc::trans Ts>
+using pc_t = ipc::prod_cons_impl<ipc::prod_cons<Rp, Rc, Ts>>;
+
+using cq_t = ipc::circ::elem_array<
+    sizeof(msg_t),
+    pc_t<ipc::relat::single, ipc::relat::multi, ipc::trans::broadcast>
+>;
 cq_t* cq__;
 
 bool operator==(msg_t const & m1, msg_t const & m2) {
@@ -67,10 +72,7 @@ struct test_verify<ipc::circ::elem_array<D, P>> {
 };
 
 template <ipc::relat Rp>
-struct test_verify<ipc::prod_cons_circ<Rp,
-        ipc::relat::multi,
-        ipc::trans::unicast>
-    > : test_verify<cq_t> {
+struct test_verify<pc_t<Rp, ipc::relat::multi, ipc::trans::unicast>> : test_verify<cq_t> {
     using test_verify<cq_t>::test_verify;
 
     void verify(int N, int Loops) {
@@ -94,12 +96,12 @@ template <typename P>
 struct quit_mode;
 
 template <ipc::relat Rp, ipc::relat Rc>
-struct quit_mode<ipc::prod_cons_circ<Rp, Rc, ipc::trans::unicast>> {
+struct quit_mode<pc_t<Rp, Rc, ipc::trans::unicast>> {
     using type = volatile bool;
 };
 
 template <ipc::relat Rp, ipc::relat Rc>
-struct quit_mode<ipc::prod_cons_circ<Rp, Rc, ipc::trans::broadcast>> {
+struct quit_mode<pc_t<Rp, Rc, ipc::trans::broadcast>> {
     struct type {
         constexpr type(bool) {}
         constexpr operator bool() const { return false; }
@@ -263,27 +265,21 @@ void test_prod_cons() {
 void Unit::test_prod_cons_1v1() {
     ipc::circ::elem_array<
         sizeof(msg_t),
-        ipc::prod_cons_circ<ipc::relat::single,
-                            ipc::relat::single,
-                            ipc::trans::unicast>
+        pc_t<ipc::relat::single, ipc::relat::single, ipc::trans::unicast>
     > el_arr_ssu;
     benchmark_prod_cons<1, 1, LoopCount, cq_t>(&el_arr_ssu);
     benchmark_prod_cons<1, 1, LoopCount, void>(&el_arr_ssu);
 
     ipc::circ::elem_array<
         sizeof(msg_t),
-        ipc::prod_cons_circ<ipc::relat::single,
-                            ipc::relat::multi,
-                            ipc::trans::unicast>
+        pc_t<ipc::relat::single, ipc::relat::multi, ipc::trans::unicast>
     > el_arr_smu;
     benchmark_prod_cons<1, 1, LoopCount, decltype(el_arr_smu)::policy_t>(&el_arr_smu);
     benchmark_prod_cons<1, 1, LoopCount, void>(&el_arr_smu);
 
     ipc::circ::elem_array<
         sizeof(msg_t),
-        ipc::prod_cons_circ<ipc::relat::multi,
-                            ipc::relat::multi,
-                            ipc::trans::unicast>
+        pc_t<ipc::relat::multi, ipc::relat::multi, ipc::trans::unicast>
     > el_arr_mmu;
     benchmark_prod_cons<1, 1, LoopCount, decltype(el_arr_mmu)::policy_t>(&el_arr_mmu);
     benchmark_prod_cons<1, 1, LoopCount, void>(&el_arr_mmu);
@@ -293,9 +289,7 @@ void Unit::test_prod_cons_1v1() {
 
     ipc::circ::elem_array<
         sizeof(msg_t),
-        ipc::prod_cons_circ<ipc::relat::multi,
-                            ipc::relat::multi,
-                            ipc::trans::broadcast>
+        pc_t<ipc::relat::multi, ipc::relat::multi, ipc::trans::broadcast>
     > el_arr_mmb;
     benchmark_prod_cons<1, 1, LoopCount, cq_t>(&el_arr_mmb);
     benchmark_prod_cons<1, 1, LoopCount, void>(&el_arr_mmb);
@@ -304,18 +298,14 @@ void Unit::test_prod_cons_1v1() {
 void Unit::test_prod_cons_1v3() {
     ipc::circ::elem_array<
         sizeof(msg_t),
-        ipc::prod_cons_circ<ipc::relat::single,
-                            ipc::relat::multi,
-                            ipc::trans::unicast>
+        pc_t<ipc::relat::single, ipc::relat::multi, ipc::trans::unicast>
     > el_arr_smu;
     benchmark_prod_cons<1, 3, LoopCount, decltype(el_arr_smu)::policy_t>(&el_arr_smu);
     benchmark_prod_cons<1, 3, LoopCount, void>(&el_arr_smu);
 
     ipc::circ::elem_array<
         sizeof(msg_t),
-        ipc::prod_cons_circ<ipc::relat::multi,
-                            ipc::relat::multi,
-                            ipc::trans::unicast>
+        pc_t<ipc::relat::multi, ipc::relat::multi, ipc::trans::unicast>
     > el_arr_mmu;
     benchmark_prod_cons<1, 3, LoopCount, decltype(el_arr_mmu)::policy_t>(&el_arr_mmu);
     benchmark_prod_cons<1, 3, LoopCount, void>(&el_arr_mmu);
@@ -325,9 +315,7 @@ void Unit::test_prod_cons_1v3() {
 
     ipc::circ::elem_array<
         sizeof(msg_t),
-        ipc::prod_cons_circ<ipc::relat::multi,
-                            ipc::relat::multi,
-                            ipc::trans::broadcast>
+        pc_t<ipc::relat::multi, ipc::relat::multi, ipc::trans::broadcast>
     > el_arr_mmb;
     benchmark_prod_cons<1, 3, LoopCount, cq_t>(&el_arr_mmb);
     benchmark_prod_cons<1, 3, LoopCount, void>(&el_arr_mmb);
@@ -336,9 +324,7 @@ void Unit::test_prod_cons_1v3() {
 void Unit::test_prod_cons_performance() {
     ipc::circ::elem_array<
         sizeof(msg_t),
-        ipc::prod_cons_circ<ipc::relat::single,
-                            ipc::relat::multi,
-                            ipc::trans::unicast>
+        pc_t<ipc::relat::single, ipc::relat::multi, ipc::trans::unicast>
     > el_arr_smu;
     ipc::detail::static_for(std::make_index_sequence<8>{}, [&el_arr_smu](auto index) {
         benchmark_prod_cons<1, decltype(index)::value + 1, LoopCount, void>(&el_arr_smu);
@@ -351,9 +337,7 @@ void Unit::test_prod_cons_performance() {
 
     ipc::circ::elem_array<
         sizeof(msg_t),
-        ipc::prod_cons_circ<ipc::relat::multi,
-                            ipc::relat::multi,
-                            ipc::trans::unicast>
+        pc_t<ipc::relat::multi, ipc::relat::multi, ipc::trans::unicast>
     > el_arr_mmu;
     ipc::detail::static_for(std::make_index_sequence<8>{}, [&el_arr_mmu](auto index) {
         benchmark_prod_cons<1, decltype(index)::value + 1, LoopCount, void>(&el_arr_mmu);
@@ -367,9 +351,7 @@ void Unit::test_prod_cons_performance() {
 
     ipc::circ::elem_array<
         sizeof(msg_t),
-        ipc::prod_cons_circ<ipc::relat::multi,
-                            ipc::relat::multi,
-                            ipc::trans::broadcast>
+        pc_t<ipc::relat::multi, ipc::relat::multi, ipc::trans::broadcast>
     > el_arr_mmb;
     ipc::detail::static_for(std::make_index_sequence<8>{}, [&el_arr_mmb](auto index) {
         benchmark_prod_cons<1, decltype(index)::value + 1, LoopCount, void>(&el_arr_mmb);
@@ -383,7 +365,12 @@ void Unit::test_prod_cons_performance() {
 }
 
 void Unit::test_queue() {
-    ipc::queue<msg_t> queue;
+    using queue_t = ipc::queue<msg_t, ipc::policy::choose<
+            ipc::circ::elem_array,
+            ipc::prod_cons<ipc::relat::single, ipc::relat::multi, ipc::trans::broadcast>
+    >>;
+    queue_t queue;
+
     queue.push(msg_t { 1, 2 });
     QCOMPARE(queue.pop(), msg_t{});
     QVERIFY(sizeof(decltype(queue)::elems_t) <= sizeof(*cq__));
@@ -393,7 +380,7 @@ void Unit::test_queue() {
     QVERIFY(queue.detach() != nullptr);
 
     ipc::detail::static_for(std::make_index_sequence<8>{}, [](auto index) {
-        benchmark_prod_cons<1, decltype(index)::value + 1, LoopCount>((ipc::queue<msg_t>*)nullptr);
+        benchmark_prod_cons<1, decltype(index)::value + 1, LoopCount>((queue_t*)nullptr);
     });
 }
 
diff --git a/test/test_ipc.cpp b/test/test_ipc.cpp
index 517b5ea..43c3426 100644
--- a/test/test_ipc.cpp
+++ b/test/test_ipc.cpp
@@ -19,7 +19,7 @@
 
 #include "ipc.h"
 #include "rw_lock.h"
-#include "memory/resource.hpp"
+#include "memory/resource.h"
 
 #include "test.h"
 
diff --git a/test/test_mem.cpp b/test/test_mem.cpp
index fa5ce31..40335b0 100644
--- a/test/test_mem.cpp
+++ b/test/test_mem.cpp
@@ -5,7 +5,7 @@
 
 #include "random.hpp"
 
-#include "memory/resource.hpp"
+#include "memory/resource.h"
 #include "pool_alloc.h"
 
 #include "test.h"