diff --git a/include/utl/container/edeque.h b/include/utl/container/edeque.h
new file mode 100644
index 0000000..8fb821f
--- /dev/null
+++ b/include/utl/container/edeque.h
@@ -0,0 +1,299 @@
+/*!
+ * \file container/edeque.h
+ * \brief
+ *      A deque with event based callables
+ *
+ * \copyright Copyright (C) 2021 Christos Choutouridis <christos@choutouridis.net>
+ *
+ * <dl class=\"section copyright\"><dt>License</dt><dd>
+ * The MIT License (MIT)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ * </dd></dl>
+ */
+
+#ifndef utl_container_edeque_h__
+#define utl_container_edeque_h__
+
+#include <utl/core/impl.h>
+#include <utl/container/deque.h>
+
+#include <functional>
+#include <utility>
+#include <type_traits>
+
+namespace utl {
+
+/*!
+ * \class edeque
+ * \brief
+ *      A statically allocated deque with size and data matching event based callables.
+ *
+ * The edeque inherits deque and provide the callable functionality as a wrapper.
+ *
+ * There are two types of events.
+ *  - Size based events, which are cleared as soon as they served. These events are checked
+ *    every time the deque change its size. If the criteria match we call the callable of type
+ *    \c Fn
+ *  - Data based events, which are permanently. These events are checked every time an item is
+ *  pushed or popped from the deque. If the criteria match we call call the callable of type
+ *    \c Fn
+ *
+ * \tparam Data_t       The char-like queued item type. Usually \c char
+ * \tparam N            The size of edeque
+ * \tparam SemiAtomic   True for semi-atomic operation. In that case the \c ring_iterator is also atomic.
+ * \tparam Fn           The type of Callable
+ * \note
+ *      SemiAtomic means it is safe to access different ends from different threads. For example one thread can
+ *      push only from front and another can pop from back to implement a queue.
+ */
+template <typename Data_t, size_t N, bool SemiAtomic =false, typename Fn = std::function<void()>>
+class edeque : public deque<Data_t, N, SemiAtomic> {
+    public:
+        // meta-identity types
+        using type                  = edeque<Data_t, N, SemiAtomic, Fn>;
+        using base_type             = deque<Data_t, N, SemiAtomic>;
+        using callable_t            = Fn;
+        using range_t               = typename base_type::range_t;
+
+        // STL
+        using value_type            = typename base_type::value_type;
+        using reference             = typename base_type::reference;
+        using const_reference       = typename base_type::const_reference;
+        using pointer               = typename base_type::pointer;
+        using const_pointer         = typename base_type::const_pointer;
+        using iterator              = typename base_type::iterator;
+        using const_iterator        = typename base_type::const_iterator;
+        using reverse_iterator      = typename base_type::reverse_iterator;
+        using const_reverse_iterator= typename base_type::const_reverse_iterator;
+
+    //! \name Public types
+    //! @{
+    public:
+        //! \enum match_mode
+        //! The mode of match operation
+        enum class match_mode { SIZE, DATA };
+        //! \enum size_match
+        //! The type of matching for size based match
+        enum class size_match { DISABLED =0, EQ, NE, LT, LE, GT, GE };
+        //! \enum data_match
+        //! The type of matching for data based match
+        enum class data_match { DISABLED =0, MATCH_PUSH, MATCH_POP, MISMATCH_PUSH, MISMATCH_POP};
+
+//        TODO: trigger mode for one-shot or repeated functionality
+//        enum class trigger_mode { ONE_SHOT, REPEATED };
+
+        //! \struct size_trigger
+        //! Size trigger data type
+        struct size_trigger {
+            size_match      type;
+            size_t          size;
+        };
+        //! \struct data_trigger
+        //! Data trigger data type
+        struct data_trigger {
+            data_match      type;
+            Data_t          value;
+        };
+        //! \union trigger
+        //! \brief
+        //!     A union for the common types.
+        //! There is only one mode. Either "size" with \ref size_match type and a size to match,
+        //! or "data" with \ref data_match type and a value to match
+        union trigger {
+            size_trigger    tsize;
+            data_trigger    tdata;
+        };
+    //! @}
+
+    //! \name Constructor / Destructor
+    //! @{
+    public:
+        //! Default constructor
+        constexpr edeque () noexcept :
+            base_type() { }
+
+        //! Size trigger constructor
+        constexpr edeque (size_match match, size_t size, callable_t&& fn) noexcept :
+            base_type(),
+            mode_{match_mode::SIZE},
+            callback_{std::forward<callable_t>(fn)} {
+            trigger_.tsize.type = match;
+            trigger_.tsize.size = size;
+        }
+        //! Data trigger constructor
+        constexpr edeque (data_match match, Data_t value, callable_t&& fn) noexcept :
+            base_type(),
+            mode_{match_mode::DATA},
+            callback_{std::forward<callable_t>(fn)} {
+            trigger_.tdata.type = match;
+            trigger_.tdata.value = value;
+        }
+    //! @}
+
+    //! \name Public interface
+    //! @{
+
+        //! \brief
+        //!     Manually checks the size trigger and calls it we have match.
+        //! \return     True if the callable has called.
+        bool check_trigger () noexcept {
+            return check_trigger_size_();
+        }
+
+        //! \brief
+        //!     Manually set (or alters) the \c size trigger. This function does not fire the
+        //! \ref check_trigger()
+        //! \param match    The match type
+        //! \param size     The size for with we check against
+        //! \param fn       The callable to call on match
+        void set_trigger (size_match match, size_t size, callable_t&& fn) noexcept {
+            mode_               = match_mode::SIZE;
+            trigger_.tsize.type = match;
+            trigger_.tsize.size = size;
+            callback_           = std::forward<callable_t>(fn);
+        }
+
+        //! \brief
+        //!     Manually set (or alters) the \c data trigger. This function does not fire the
+        //! \ref check_trigger()
+        //! \param match    The match type
+        //! \param value    The value for with we check against
+        //! \param fn       The callable to call on match
+        void set_trigger (data_match match, Data_t value, callable_t&& fn) noexcept {
+            mode_               = match_mode::DATA;
+            trigger_.tdata.type = match;
+            trigger_.tdata.value= value;
+            callback_           = std::forward<callable_t>(fn);
+        }
+
+        //! \brief Manually clears the trigger
+        void clear_trigger () noexcept {
+            mode_       = match_mode{};
+            trigger_    = trigger{};
+            callback_   = callable_t{};
+        }
+    //! @}
+
+    //!  \name Base class uses and overwrites
+    //! @{
+        void push_front (const Data_t& it) noexcept {
+            base_type::push_front(it);
+            check_trigger_push_async_(it);
+        }
+        void push_back (const Data_t& it) noexcept {
+            base_type::push_back(it);
+            check_trigger_push_async_(it);
+        }
+        Data_t pop_front () noexcept {
+            Data_t t = base_type::pop_front();
+            check_trigger_pop_async_(t);
+            return t;
+        }
+        Data_t pop_back () noexcept {
+            Data_t t = base_type::pop_back();
+            check_trigger_pop_async_(t);
+            return t;
+        }
+    //! @}
+
+    //! \name Private functionality
+    //! @{
+    private:
+        //! \brief
+        //!     Manually checks the size trigger and calls it we have match.
+        //! \return     True if the callable has called.
+        bool check_trigger_size_ () {
+            bool match;
+            switch (trigger_.tsize.type) {
+                default:
+                case size_match::DISABLED:  match = false; break;
+                case size_match::EQ:        match = (base_type::size() == trigger_.tsize.size); break;
+                case size_match::NE:        match = (base_type::size() != trigger_.tsize.size); break;
+                case size_match::LT:        match = (base_type::size() <  trigger_.tsize.size); break;
+                case size_match::LE:        match = (base_type::size() <= trigger_.tsize.size); break;
+                case size_match::GT:        match = (base_type::size() >  trigger_.tsize.size); break;
+                case size_match::GE:        match = (base_type::size() >= trigger_.tsize.size); break;
+            }
+            if (match) {
+                callback_();
+                clear_trigger();
+            }
+            return match;
+        }
+
+        //! \brief
+        //!     Manually checks the data trigger on push and calls it we have match.
+        //! \param  it  The item to check against
+        //! \return     True if the callable has called.
+        bool check_trigger_push_value_ (const Data_t& it) {
+            bool match;
+            switch (trigger_.tdata.type) {
+                default:
+                case data_match::DISABLED:      match = false;  break;
+                case data_match::MATCH_PUSH:    match = (it == trigger_.tdata.value); break;
+                case data_match::MISMATCH_PUSH: match = (it != trigger_.tdata.value); break;
+            }
+            if (match)
+                callback_();
+            return match;
+        }
+
+        //! \brief
+        //!     Manually checks the data trigger on pop and calls it we have match.
+        //! \param  it  The item to check against
+        //! \return     True if the callable has called.
+        bool check_trigger_pop_value_ (const Data_t& it) {
+            bool match;
+            switch (trigger_.tdata.type) {
+                default:
+                case data_match::DISABLED:      match = false;  break;
+                case data_match::MATCH_POP:     match = (it == trigger_.tdata.value); break;
+                case data_match::MISMATCH_POP:  match = (it != trigger_.tdata.value); break;
+            }
+            if (match)
+                callback_();
+            return match;
+        }
+
+        //! Wrapper for both triggers at push
+        bool check_trigger_push_async_ (const Data_t& it) {
+            switch (mode_) {
+                default:
+                case match_mode::SIZE:  return check_trigger_size_();
+                case match_mode::DATA:  return check_trigger_push_value_(it);
+            }
+        }
+        //! Wrapper for both triggers at pop
+        bool check_trigger_pop_async_ (const Data_t& it) {
+            switch (mode_) {
+                default:
+                case match_mode::SIZE:  return check_trigger_size_();
+                case match_mode::DATA:  return check_trigger_pop_value_(it);
+            }
+        }
+    //! @}
+    private:
+        match_mode  mode_{};
+        trigger     trigger_{};
+        callable_t  callback_{};
+};
+} // namespace utl
+
+#endif /* utl_container_edeque_h__ */
diff --git a/include/utl/container/equeue.h b/include/utl/container/equeue.h
new file mode 100644
index 0000000..b1816f4
--- /dev/null
+++ b/include/utl/container/equeue.h
@@ -0,0 +1,146 @@
+/*!
+ * \file container/equeue.h
+ * \brief
+ *      A queue with event based callables based on edeque.
+ *
+ * \copyright Copyright (C) 2021 Christos Choutouridis <christos@choutouridis.net>
+ *
+ * <dl class=\"section copyright\"><dt>License</dt><dd>
+ * The MIT License (MIT)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ * </dd></dl>
+ */
+
+#ifndef utl_container_equeue_h__
+#define utl_container_equeue_h__
+
+#include <utl/core/impl.h>
+#include <utl/container/edeque.h>
+
+namespace utl {
+
+/*!
+ * \class equeue
+ * \brief
+ *      A statically allocated queue based on edeque with size and data matching
+ *      event based callables.
+ *
+ * We use the \ref edeque::push_back() and \ref edeque::pop_front() pair from edeque's
+ * functionality, so at the \c push the increment performed after the insertion.
+ * Similarly at the \c pop the decrement performed before the exctraction. This way also
+ * the \ref edeque::front() and \ref edeque::back() stay the same ;)
+ *
+ * We also provide stream operators.
+ *
+ * \tparam Data_t       The char-like queued item type. Usually \c char
+ * \tparam N            The size of edeque
+ * \tparam SemiAtomic   True for semi-atomic operation. In that case the \c ring_iterator is also atomic.
+ * \tparam Fn           The type of Callable
+ * \note
+ *      SemiAtomic means it is safe to for one thread to  push only from front and another can pop.
+ */
+template <typename Data_t, size_t N, bool SemiAtomic =false, typename Fn = std::function<void()>>
+class equeue : public edeque<Data_t, N, SemiAtomic, Fn> {
+    public:
+        // meta-identity types
+        using equeue_t              = equeue<Data_t, N, SemiAtomic, Fn>;
+        using base_type             = edeque<Data_t, N, SemiAtomic, Fn>;
+        using range_t               = typename base_type::range_t;
+
+        // STL
+        using value_type            = typename base_type::value_type;
+        using reference             = typename base_type::reference;
+        using const_reference       = typename base_type::const_reference;
+        using pointer               = typename base_type::pointer;
+        using const_pointer         = typename base_type::const_pointer;
+        using iterator              = typename base_type::iterator;
+        using const_iterator        = typename base_type::const_iterator;
+        using reverse_iterator      = typename base_type::reverse_iterator;
+        using const_reverse_iterator= typename base_type::const_reverse_iterator;
+
+    //! \name Constructor / Destructor
+    //! @{
+    public:
+        //! Default constructor
+        constexpr equeue () noexcept : base_type() { }
+
+        //! Forward constructor
+        template <typename ...It>
+        constexpr equeue(It&& ...it) noexcept : base_type(std::forward<It>(it)...) { }
+
+    //! @}
+
+    //! \name Member access
+    //! @{
+    public:
+        //! \brief      Push an item in the back of the queue
+        //! \param it   The item to push
+        void push (const Data_t& it) noexcept {
+            base_type::push_back(it);
+        }
+
+        //! \brief      Extract an item from the front of the queue and remove it from the queue
+        //! \param it   The item to push
+        Data_t pop () noexcept {
+            return base_type::pop_front();
+        }
+
+        //! \brief      Push an item in the back of the queue
+        //! \param it   The item to push
+        equeue_t& operator<< (const Data_t& it) noexcept {
+            push(it);
+            return *this;
+        }
+
+        //! \brief      Push an item in the back of the queue
+        //! \param it   The item to push
+        equeue_t& operator>> (Data_t& it) noexcept {
+            it = pop();
+            return *this;
+        }
+
+    //! @}
+
+};
+
+/*!
+ * \brief
+ *      Pop an item from the front of the queue.
+ *
+ *  This definition enables the "data << equeue" syntax for pop operation
+ *
+ *  \tparam Data_t      The char-like queued item type. Usually \c char
+ *  \tparam N           The size of queue
+ *  \tparam SemiAtomic  True for semi-atomic operation. In that case the \c ring_iterator is also atomic.
+ *  \tparam Fn          The type of Callable
+ *
+ *  \param it       The item to write to
+ *  \param q        The queue to read from
+ *  \return         Reference to the returned item
+ */
+template <typename Data_t, size_t N, bool SemiAtomic =false, typename Fn = std::function<void()>>
+Data_t& operator<< (Data_t& it, equeue<Data_t, N, SemiAtomic, Fn>& q) noexcept {
+    it = q.pop();
+    return it;
+}
+
+} // namespace utl
+
+#endif /* utl_container_equeue_h__ */
diff --git a/include/utl/container/queue.h b/include/utl/container/queue.h
new file mode 100644
index 0000000..67110e1
--- /dev/null
+++ b/include/utl/container/queue.h
@@ -0,0 +1,144 @@
+/*!
+ * \file container/queue.h
+ * \brief
+ *      A statically allocated queue based on deque.
+ *
+ * \copyright Copyright (C) 2021 Christos Choutouridis <christos@choutouridis.net>
+ *
+ * <dl class=\"section copyright\"><dt>License</dt><dd>
+ * The MIT License (MIT)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ * </dd></dl>
+ */
+
+#ifndef utl_container_queue_h__
+#define utl_container_queue_h__
+
+#include <utl/core/impl.h>
+#include <utl/container/deque.h>
+
+namespace utl {
+
+/*!
+ * \class queue
+ * \brief
+ *      A statically allocated queue based on deque.
+ *
+ * We use the \ref deque::push_back() and \ref deque::pop_front() pair from deque's
+ * functionality, so at the \c push the increment performed after the insertion.
+ * Similarly at the \c pop the decrement performed before the exctraction. This way also
+ * the \ref deque::front() and \ref deque::back() stay the same ;)
+ *
+ * We also provide stream operators.
+ *
+ * \tparam Data_t       The char-like queued item type. Usually \c char
+ * \tparam N            The size of queue
+ * \tparam SemiAtomic   True for semi-atomic operation. In that case the \c ring_iterator is also atomic.
+ * \note
+ *      SemiAtomic means it is safe to for one thread to  push only from front and another can pop.
+ */
+template <typename Data_t, size_t N, bool SemiAtomic =false>
+class queue : public deque<Data_t, N, SemiAtomic> {
+    public:
+        // meta-identity types
+        using queue_t               = queue<Data_t, N, SemiAtomic>;
+        using base_type             = deque<Data_t, N, SemiAtomic>;
+        using range_t               = typename base_type::range_t;
+
+        // STL
+        using value_type            = typename base_type::value_type;
+        using reference             = typename base_type::reference;
+        using const_reference       = typename base_type::const_reference;
+        using pointer               = typename base_type::pointer;
+        using const_pointer         = typename base_type::const_pointer;
+        using iterator              = typename base_type::iterator;
+        using const_iterator        = typename base_type::const_iterator;
+        using reverse_iterator      = typename base_type::reverse_iterator;
+        using const_reverse_iterator= typename base_type::const_reverse_iterator;
+
+    //! \name Constructor / Destructor
+    //! @{
+    public:
+        //! Default constructor
+        constexpr queue () noexcept : base_type() { }
+
+        //! fill contructor
+        constexpr queue(const Data_t& value) noexcept : base_type(value) { }
+
+        //! Initializer list contructor
+        template <typename ...It>
+        constexpr queue(It&& ...it) noexcept : base_type(std::forward<It>(it)...) { }
+
+    //! @}
+
+    //! \name Member access
+    //! @{
+    public:
+        //! \brief      Push an item in the back of the queue
+        //! \param it   The item to push
+        constexpr void push (const Data_t& it) noexcept {
+            base_type::push_back(it);
+        }
+
+        //! \brief      Extract an item from the front of the queue and remove it from the queue
+        //! \param it   The item to push
+        constexpr Data_t pop () noexcept {
+            return base_type::pop_front();
+        }
+
+        //! \brief      Push an item in the back of the queue
+        //! \param it   The item to push
+        constexpr queue_t& operator<< (const Data_t& it) noexcept {
+            push(it);
+            return *this;
+        }
+
+        //! \brief      Pop an item from the front of the queue
+        //! \param it   The item to write to
+        constexpr queue_t& operator>> (Data_t& it) noexcept {
+            it = pop();
+            return *this;
+        }
+    //! @}
+};
+
+/*!
+ * \brief
+ *      Pop an item from the front of the queue.
+ *
+ *  This definition enables the "data << queue" syntax for pop operation
+ *
+ *  \tparam Data_t      The char-like queued item type. Usually \c char
+ *  \tparam N           The size of queue
+ *  \tparam SemiAtomic  True for semi-atomic operation. In that case the \c ring_iterator is also atomic.
+ *
+ *  \param it       The item to write to
+ *  \param q        The queue to read from
+ *  \return         Reference to the returned item
+ */
+template <typename Data_t, size_t N, bool SemiAtomic =false>
+constexpr Data_t& operator<< (Data_t& it, queue<Data_t, N, SemiAtomic>& q) noexcept {
+    it = q.pop();
+    return it;
+}
+
+} // namespace utl
+
+#endif /* utl_container_queue_h__ */
diff --git a/test/tests/edeque.cpp b/test/tests/edeque.cpp
new file mode 100644
index 0000000..aa31995
--- /dev/null
+++ b/test/tests/edeque.cpp
@@ -0,0 +1,555 @@
+/*!
+ * \file deque.cpp
+ * \brief
+ *      Unit tests for edeque
+ *
+ * \copyright Copyright (C) 2020 Christos Choutouridis <christos@choutouridis.net>
+ *
+ * <dl class=\"section copyright\"><dt>License</dt><dd>
+ * The MIT License (MIT)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ * </dd></dl>
+ *
+ */
+#include <utl/container/edeque.h>
+#include <gtest/gtest.h>
+
+#include <functional>
+
+namespace Tedeque {
+    using namespace utl;
+
+    int global_flag =0;
+
+    // Callable mocks
+    void vfun(void) { ++global_flag; }
+
+    struct vfoo {
+       void operator() (void) { ++global_flag; }
+    };
+
+
+    TEST (Tedeque, construct) {
+        using Edeque = edeque<int, 8>;
+        struct T { int a,b; };
+        int local{};
+
+        Edeque e1(Edeque::size_match::GE, 3, [](){
+            ++global_flag;
+        });
+        Edeque e2(Edeque::size_match::GE, 3, [&](){
+            ++local;
+        });
+        Edeque e3(Edeque::size_match::EQ, 7, vfun);
+        edeque<T, 8> e4(edeque<T, 8>::size_match::EQ, 2, vfoo{});
+
+        edeque<int, 8> q1;
+        edeque<int, 8> q2(edeque<int, 8>::size_match::DISABLED, 0, nullptr);
+
+        EXPECT_EQ (8UL, e1.capacity());
+        EXPECT_EQ (8UL, e2.capacity());
+        EXPECT_EQ (8UL, e3.capacity());
+        EXPECT_EQ (8UL, e4.capacity());
+
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q2.capacity());
+    }
+
+    TEST (Tedeque, base_class) {
+        using Edeque = edeque<int, 8>;
+
+        Edeque e1(Edeque::size_match::GE, 3, [](){
+            ++global_flag;
+        });
+
+        // Access of base class functionality
+        EXPECT_EQ (8UL, e1.capacity());
+        EXPECT_EQ (0UL, e1.size());
+        EXPECT_EQ (true, e1.empty());
+        EXPECT_EQ (false, e1.full());
+
+        e1.push_back(7);
+        EXPECT_EQ (7, e1.front());
+        EXPECT_EQ (7, e1.back());
+        EXPECT_EQ (7, e1.pop_front());
+
+        e1.push_front(42);
+        EXPECT_EQ (42, e1.front());
+        EXPECT_EQ (42, e1.back());
+        EXPECT_EQ (42, e1.pop_back());
+
+        e1.push_back(1);
+        e1.push_back(2);
+        e1.push_back(3);
+
+        int check_it=1;
+        for (auto it = e1.begin() ; it != e1.end() ; ++it)
+            EXPECT_EQ(*it, check_it++);
+        EXPECT_EQ(4, check_it);         // run through all
+    }
+
+    TEST (Tedeque, set_clear_check_trigger) {
+        using Edeque = edeque<int, 8>;
+        bool flag{};
+
+        Edeque e1(Edeque::size_match::GE, 1, [&](){ flag = true; });
+
+        flag = false;
+        e1.clear_trigger();
+        EXPECT_EQ (false, flag);
+        e1.push_back(1);            // 1,  no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        flag = false;
+        e1.clear();
+        e1.clear_trigger();
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e1.push_back(1);            // 1
+        e1.push_back(2);            // 2
+        e1.set_trigger(Edeque::size_match::GE, 1, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e1.check_trigger();         // manual trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        e1.check_trigger();         // manual trigger attempt
+        EXPECT_EQ (false, flag);    // [SIZE triggers are auto clear]
+
+        Edeque e2(Edeque::data_match::MATCH_PUSH, 42, [&](){ flag = true; });
+        flag = false;
+        e2.clear_trigger();
+        EXPECT_EQ (false, flag);
+        e2.push_back(42);           // push 42, no-trigger cleared
+        EXPECT_EQ (false, flag);
+        e2.set_trigger(Edeque::data_match::MATCH_PUSH, 42, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e2.push_back(42);           // push 42, trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        e2.push_back(42);           // push 42, re-trigger [DATA re-triggers]
+        EXPECT_EQ (true, flag);
+    }
+
+    TEST (Tedeque, size_triggers) {
+        using Edeque = edeque<int, 8>;
+        bool flag{};
+
+        // size_match::GE (size()>= 2)
+        Edeque ee(Edeque::size_match::GE, 2, [&](){ flag = true; });
+
+        flag = false;
+        ee.clear();
+        ee.push_back(1);            // 1
+        EXPECT_EQ (false, flag);
+        ee.push_back(2);            // 2, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.push_back(3);            // 3, no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        // size_match::GT (size()> 1)
+        flag = false;
+        ee.clear();
+        ee.set_trigger(Edeque::size_match::GT, 1, [&](){ flag = true; });
+        ee.push_back(1);            // 1
+        EXPECT_EQ (false, flag);
+        ee.push_back(2);            // 2, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.push_back(3);            // 3, no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        // size_match::LE (size()<= 1)
+        flag = false;
+        ee.clear();
+        ee.push_back(1);            // 1
+        ee.push_back(2);            // 2
+        ee.push_back(3);            // 3
+        ee.set_trigger(Edeque::size_match::LE, 1, [&](){ flag = true; });
+        ee.pop_front();             // 2
+        EXPECT_EQ (false, flag);
+        ee.pop_front();             // 1, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.pop_front();             // 0, no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        // size_match::LT (size()< 2)
+        flag = false;
+        ee.clear();
+        ee.push_back(1);            // 1
+        ee.push_back(2);            // 2
+        ee.push_back(3);            // 3
+        ee.set_trigger(Edeque::size_match::LT, 2, [&](){ flag = true; });
+        ee.pop_front();             // 2
+        EXPECT_EQ (false, flag);
+        ee.pop_front();             // 1, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.pop_front();             // 0, no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        // size_match::EQ (size()== 2)
+        flag = false;
+        ee.clear();
+        ee.set_trigger(Edeque::size_match::EQ, 2, [&](){ flag = true; });
+        ee.push_back(1);            // 1
+        EXPECT_EQ (false, flag);
+        ee.push_back(2);            // 2, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.push_back(3);            // 3
+        ee.pop_front();             // 2, no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        // size_match::NE (size()!= 0)
+        flag = false;
+        ee.clear();
+        ee.set_trigger(Edeque::size_match::NE, 0, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);
+        ee.push_back(1);            // 1, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.push_back(2);            // 2, no-trigger
+        EXPECT_EQ (false, flag);
+    }
+
+    TEST (Tedeque, data_triggers) {
+        using Edeque = edeque<int, 8>;
+        bool flag{};
+
+        // data_match::MATCH_PUSH (item == 42)
+        Edeque ee(Edeque::data_match::MATCH_PUSH, 42, [&](){ flag = true; });
+
+        flag = false;
+        ee.push_back(7);            // 7
+        EXPECT_EQ (false, flag);
+        ee.push_back(42);           // push:42, trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        ee.pop_back();              // pop:42, no-trigger
+        EXPECT_EQ (false, flag);
+        ee.push_back(42);           // push:42, re-trigger
+        EXPECT_EQ (true, flag);
+
+        // data_match::MATCH_POP (item == 42)
+        flag = false;
+        ee.clear_trigger();
+        ee.set_trigger(Edeque::data_match::MATCH_POP, 42, [&](){ flag = true; });
+        ee.push_back(7);            // 7
+        EXPECT_EQ (false, flag);
+        ee.push_back(42);           // push:42, no-trigger
+        EXPECT_EQ (false, flag);
+        ee.pop_back();              // pop:42, trigger
+        EXPECT_EQ (true, flag);
+
+        // data_match::MISMATCH_PUSH (item != 42)
+        flag = false;
+        ee.clear();
+        ee.clear_trigger();
+        ee.push_back(7);            // 7
+        ee.set_trigger(Edeque::data_match::MISMATCH_PUSH, 42, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        ee.push_back(42);           // 42, no-trigger
+        EXPECT_EQ (false, flag);
+        ee.push_back(0);            // 0, trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        ee.push_back(1);            // 1, re-trigger
+        EXPECT_EQ (true, flag);
+
+        // data_match::MISMATCH_POP (item != 42)
+        flag = false;
+        ee.clear();
+        ee.clear_trigger();
+        ee.push_back(7);            // ->7
+        ee.pop_back();              // <-7
+        ee.set_trigger(Edeque::data_match::MISMATCH_POP, 42, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        ee.push_back(42);           // ->42, no-trigger
+        EXPECT_EQ (false, flag);
+        ee.push_back(0);            // ->0, no-trigger
+        EXPECT_EQ (false, flag);
+        ee.pop_back();              // pop:0, trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        ee.push_back(0);
+        ee.pop_back();              // pop:0, re-trigger
+        EXPECT_EQ (true, flag);
+    }
+
+    // atomic
+    TEST (Tedeque, construct_atomic) {
+        using Edeque = edeque<int, 8, true>;
+        struct T { int a,b; };
+        int local{};
+
+        Edeque e1(Edeque::size_match::GE, 3, [](){
+            ++global_flag;
+        });
+        Edeque e2(Edeque::size_match::GE, 3, [&](){
+            ++local;
+        });
+        Edeque e3(Edeque::size_match::EQ, 7, vfun);
+        edeque<T, 8> e4(edeque<T, 8>::size_match::EQ, 2, vfoo{});
+
+        edeque<int, 8, true> q1;
+        edeque<int, 8, true> q2(edeque<int, 8, true>::size_match::DISABLED, 0, nullptr);
+
+        EXPECT_EQ (8UL, e1.capacity());
+        EXPECT_EQ (8UL, e2.capacity());
+        EXPECT_EQ (8UL, e3.capacity());
+        EXPECT_EQ (8UL, e4.capacity());
+
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q2.capacity());
+    }
+
+    TEST (Tedeque, base_class_atomic) {
+        using Edeque = edeque<int, 8, true>;
+
+        Edeque e1(Edeque::size_match::GE, 3, [](){
+            ++global_flag;
+        });
+
+        // Access of base class functionality
+        EXPECT_EQ (8UL, e1.capacity());
+        EXPECT_EQ (0UL, e1.size());
+        EXPECT_EQ (true, e1.empty());
+        EXPECT_EQ (false, e1.full());
+
+        e1.push_back(7);
+        EXPECT_EQ (7, e1.front());
+        EXPECT_EQ (7, e1.back());
+        EXPECT_EQ (7, e1.pop_front());
+
+        e1.push_front(42);
+        EXPECT_EQ (42, e1.front());
+        EXPECT_EQ (42, e1.back());
+        EXPECT_EQ (42, e1.pop_back());
+
+        e1.push_back(1);
+        e1.push_back(2);
+        e1.push_back(3);
+
+        int check_it=1;
+        for (auto it = e1.begin() ; it != e1.end() ; ++it)
+            EXPECT_EQ(*it, check_it++);
+        EXPECT_EQ(4, check_it);         // run through all
+    }
+
+    TEST (Tedeque, set_clear_check_trigger_atomic) {
+        using Edeque = edeque<int, 8, true>;
+        bool flag{};
+
+        Edeque e1(Edeque::size_match::GE, 1, [&](){ flag = true; });
+
+        flag = false;
+        e1.clear_trigger();
+        EXPECT_EQ (false, flag);
+        e1.push_back(1);            // 1,  no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        flag = false;
+        e1.clear();
+        e1.clear_trigger();
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e1.push_back(1);            // 1
+        e1.push_back(2);            // 2
+        e1.set_trigger(Edeque::size_match::GE, 1, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e1.check_trigger();         // manual trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        e1.check_trigger();         // manual trigger attempt
+        EXPECT_EQ (false, flag);    // [SIZE triggers are auto clear]
+
+        Edeque e2(Edeque::data_match::MATCH_PUSH, 42, [&](){ flag = true; });
+        flag = false;
+        e2.clear_trigger();
+        EXPECT_EQ (false, flag);
+        e2.push_back(42);           // push 42, no-trigger cleared
+        EXPECT_EQ (false, flag);
+        e2.set_trigger(Edeque::data_match::MATCH_PUSH, 42, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e2.push_back(42);           // push 42, trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        e2.push_back(42);           // push 42, re-trigger [DATA re-triggers]
+        EXPECT_EQ (true, flag);
+    }
+
+    TEST (Tedeque, size_triggers_atomic) {
+        using Edeque = edeque<int, 8, true>;
+        bool flag{};
+
+        // size_match::GE (size()>= 2)
+        Edeque ee(Edeque::size_match::GE, 2, [&](){ flag = true; });
+
+        flag = false;
+        ee.clear();
+        ee.push_back(1);            // 1
+        EXPECT_EQ (false, flag);
+        ee.push_back(2);            // 2, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.push_back(3);            // 3, no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        // size_match::GT (size()> 1)
+        flag = false;
+        ee.clear();
+        ee.set_trigger(Edeque::size_match::GT, 1, [&](){ flag = true; });
+        ee.push_back(1);            // 1
+        EXPECT_EQ (false, flag);
+        ee.push_back(2);            // 2, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.push_back(3);            // 3, no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        // size_match::LE (size()<= 1)
+        flag = false;
+        ee.clear();
+        ee.push_back(1);            // 1
+        ee.push_back(2);            // 2
+        ee.push_back(3);            // 3
+        ee.set_trigger(Edeque::size_match::LE, 1, [&](){ flag = true; });
+        ee.pop_front();             // 2
+        EXPECT_EQ (false, flag);
+        ee.pop_front();             // 1, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.pop_front();             // 0, no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        // size_match::LT (size()< 2)
+        flag = false;
+        ee.clear();
+        ee.push_back(1);            // 1
+        ee.push_back(2);            // 2
+        ee.push_back(3);            // 3
+        ee.set_trigger(Edeque::size_match::LT, 2, [&](){ flag = true; });
+        ee.pop_front();             // 2
+        EXPECT_EQ (false, flag);
+        ee.pop_front();             // 1, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.pop_front();             // 0, no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        // size_match::EQ (size()== 2)
+        flag = false;
+        ee.clear();
+        ee.set_trigger(Edeque::size_match::EQ, 2, [&](){ flag = true; });
+        ee.push_back(1);            // 1
+        EXPECT_EQ (false, flag);
+        ee.push_back(2);            // 2, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.push_back(3);            // 3
+        ee.pop_front();             // 2, no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        // size_match::NE (size()!= 0)
+        flag = false;
+        ee.clear();
+        ee.set_trigger(Edeque::size_match::NE, 0, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);
+        ee.push_back(1);            // 1, trigger
+        EXPECT_EQ (true, flag);
+        flag = false;
+        ee.push_back(2);            // 2, no-trigger
+        EXPECT_EQ (false, flag);
+    }
+
+    TEST (Tedeque, data_triggers_atomic) {
+        using Edeque = edeque<int, 8, true>;
+        bool flag{};
+
+        // data_match::MATCH_PUSH (item == 42)
+        Edeque ee(Edeque::data_match::MATCH_PUSH, 42, [&](){ flag = true; });
+
+        flag = false;
+        ee.push_back(7);            // 7
+        EXPECT_EQ (false, flag);
+        ee.push_back(42);           // push:42, trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        ee.pop_back();              // pop:42, no-trigger
+        EXPECT_EQ (false, flag);
+        ee.push_back(42);           // push:42, re-trigger
+        EXPECT_EQ (true, flag);
+
+        // data_match::MATCH_POP (item == 42)
+        flag = false;
+        ee.clear_trigger();
+        ee.set_trigger(Edeque::data_match::MATCH_POP, 42, [&](){ flag = true; });
+        ee.push_back(7);            // 7
+        EXPECT_EQ (false, flag);
+        ee.push_back(42);           // push:42, no-trigger
+        EXPECT_EQ (false, flag);
+        ee.pop_back();              // pop:42, trigger
+        EXPECT_EQ (true, flag);
+
+        // data_match::MISMATCH_PUSH (item != 42)
+        flag = false;
+        ee.clear();
+        ee.clear_trigger();
+        ee.push_back(7);            // 7
+        ee.set_trigger(Edeque::data_match::MISMATCH_PUSH, 42, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        ee.push_back(42);           // 42, no-trigger
+        EXPECT_EQ (false, flag);
+        ee.push_back(0);            // 0, trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        ee.push_back(1);            // 1, re-trigger
+        EXPECT_EQ (true, flag);
+
+        // data_match::MISMATCH_POP (item != 42)
+        flag = false;
+        ee.clear();
+        ee.clear_trigger();
+        ee.push_back(7);            // ->7
+        ee.pop_back();              // <-7
+        ee.set_trigger(Edeque::data_match::MISMATCH_POP, 42, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        ee.push_back(42);           // ->42, no-trigger
+        EXPECT_EQ (false, flag);
+        ee.push_back(0);            // ->0, no-trigger
+        EXPECT_EQ (false, flag);
+        ee.pop_back();              // pop:0, trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        ee.push_back(0);
+        ee.pop_back();              // pop:0, re-trigger
+        EXPECT_EQ (true, flag);
+    }
+}
diff --git a/test/tests/equeue.cpp b/test/tests/equeue.cpp
new file mode 100644
index 0000000..37d21d5
--- /dev/null
+++ b/test/tests/equeue.cpp
@@ -0,0 +1,317 @@
+/*!
+ * \file equeue.cpp
+ * \brief
+ *      Unit tests for equeue
+ *
+ * \copyright Copyright (C) 2020 Christos Choutouridis <christos@choutouridis.net>
+ *
+ * <dl class=\"section copyright\"><dt>License</dt><dd>
+ * The MIT License (MIT)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ * </dd></dl>
+ *
+ */
+#include <utl/container/equeue.h>
+#include <gtest/gtest.h>
+
+namespace Tequeue {
+    using namespace utl;
+
+    int global_flag =0;
+
+    // Callable mocks
+    void vfun(void) { ++global_flag; }
+
+    struct vfoo {
+       void operator() (void) { ++global_flag; }
+    };
+
+    // Test construction
+    TEST(Tequeue, contruct) {
+        using Equeue = equeue<int, 8>;
+        struct T { int a,b; };
+        int local{};
+
+        Equeue e1(Equeue::size_match::GE, 3, [](){
+            ++global_flag;
+        });
+        Equeue e2(Equeue::size_match::GE, 3, [&](){
+            ++local;
+        });
+        Equeue e3(Equeue::size_match::EQ, 7, vfun);
+        equeue<T, 8> e4(equeue<T, 8>::size_match::EQ, 2, vfoo{});
+
+        equeue<int, 8> q1;
+        equeue<int, 8> q2(equeue<int, 8>::size_match::DISABLED, 0, nullptr);
+
+        EXPECT_EQ (8UL, e1.capacity());
+        EXPECT_EQ (8UL, e2.capacity());
+        EXPECT_EQ (8UL, e3.capacity());
+        EXPECT_EQ (8UL, e4.capacity());
+
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q2.capacity());
+    }
+
+    // simple push-pop functionality
+    TEST(Tequeue, base_class) {
+        using Equeue = equeue<int, 8>;
+
+        Equeue e1(Equeue::size_match::GE, 3, [](){
+            ++global_flag;
+        });
+
+        // Access of base class functionality
+        EXPECT_EQ (8UL, e1.capacity());
+        EXPECT_EQ (0UL, e1.size());
+        EXPECT_EQ (true, e1.empty());
+        EXPECT_EQ (false, e1.full());
+
+        e1.push(42);
+        EXPECT_EQ (42, e1.front());
+        EXPECT_EQ (42, e1.back());
+        EXPECT_EQ (42, e1.pop());
+
+        e1.push(1);
+        e1.push(2);
+        e1.push(3);
+
+        int check_it=1;
+        for (auto it = e1.begin() ; it != e1.end() ; ++it)
+            EXPECT_EQ(*it, check_it++);
+        EXPECT_EQ(4, check_it);         // run through all
+
+    }
+
+    // trigger functionality
+    TEST (Tequeue, set_clear_check_trigger) {
+        using Equeue = equeue<int, 8>;
+        bool flag{};
+
+        Equeue e1(Equeue::size_match::GE, 1, [&](){ flag = true; });
+
+        flag = false;
+        e1.clear_trigger();
+        EXPECT_EQ (false, flag);
+        e1.push_back(1);            // 1,  no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        flag = false;
+        e1.clear();
+        e1.clear_trigger();
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e1.push_back(1);            // 1
+        e1.push_back(2);            // 2
+        e1.set_trigger(Equeue::size_match::GE, 1, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e1.check_trigger();         // manual trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        e1.check_trigger();         // manual trigger attempt
+        EXPECT_EQ (false, flag);    // [SIZE triggers are auto clear]
+
+        Equeue e2(Equeue::data_match::MATCH_PUSH, 42, [&](){ flag = true; });
+        flag = false;
+        e2.clear_trigger();
+        EXPECT_EQ (false, flag);
+        e2.push_back(42);           // push 42, no-trigger cleared
+        EXPECT_EQ (false, flag);
+        e2.set_trigger(Equeue::data_match::MATCH_PUSH, 42, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e2.push_back(42);           // push 42, trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        e2.push_back(42);           // push 42, re-trigger [DATA re-triggers]
+        EXPECT_EQ (true, flag);
+    }
+
+    // stream push-pop
+    TEST(Tequeue, stream_push_pop) {
+        equeue<int, 8> q1;
+
+        q1 << 1 << 2 << 3 << 4 << 5 << 6 << 7 << 8;
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q1.size());
+        EXPECT_EQ (false, q1.empty());
+        EXPECT_EQ (true, q1.full());
+
+        q1 << 9;                        // try to insert in full queue
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q1.size());
+        EXPECT_EQ (false, q1.empty());
+        EXPECT_EQ (true, q1.full());
+
+        int check_it=1;
+        for (auto it = q1.begin() ; it != q1.end() ; ++it)
+            EXPECT_EQ(*it, check_it++);
+        EXPECT_EQ(9, check_it);         // run through all
+
+        for (int i =1 ; i <= 8 ; ++i) {
+            check_it << q1;
+            EXPECT_EQ(i, check_it);
+        }
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (0UL, q1.size());
+        EXPECT_EQ (true, q1.empty());
+        EXPECT_EQ (false, q1.full());
+
+        q1 >> check_it;
+        EXPECT_EQ (int{}, check_it);
+    }
+
+    // atomic
+    // Test construction
+    TEST(Tequeue, contruct_atomic) {
+        using Equeue = equeue<int, 8, true>;
+        struct T { int a,b; };
+        int local{};
+
+        Equeue e1(Equeue::size_match::GE, 3, [](){
+            ++global_flag;
+        });
+        Equeue e2(Equeue::size_match::GE, 3, [&](){
+            ++local;
+        });
+        Equeue e3(Equeue::size_match::EQ, 7, vfun);
+        equeue<T, 8> e4(equeue<T, 8>::size_match::EQ, 2, vfoo{});
+
+        equeue<int, 8, true> q1;
+        equeue<int, 8, true> q2(equeue<int, 8, true>::size_match::DISABLED, 0, nullptr);
+
+        EXPECT_EQ (8UL, e1.capacity());
+        EXPECT_EQ (8UL, e2.capacity());
+        EXPECT_EQ (8UL, e3.capacity());
+        EXPECT_EQ (8UL, e4.capacity());
+
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q2.capacity());
+    }
+
+    // simple push-pop functionality
+    TEST(Tequeue, base_class_atomic) {
+        using Equeue = equeue<int, 8, true>;
+
+        Equeue e1(Equeue::size_match::GE, 3, [](){
+            ++global_flag;
+        });
+
+        // Access of base class functionality
+        EXPECT_EQ (8UL, e1.capacity());
+        EXPECT_EQ (0UL, e1.size());
+        EXPECT_EQ (true, e1.empty());
+        EXPECT_EQ (false, e1.full());
+
+        e1.push(42);
+        EXPECT_EQ (42, e1.front());
+        EXPECT_EQ (42, e1.back());
+        EXPECT_EQ (42, e1.pop());
+
+        e1.push(1);
+        e1.push(2);
+        e1.push(3);
+
+        int check_it=1;
+        for (auto it = e1.begin() ; it != e1.end() ; ++it)
+            EXPECT_EQ(*it, check_it++);
+        EXPECT_EQ(4, check_it);         // run through all
+
+    }
+
+    // trigger functionality
+    TEST (Tequeue, set_clear_check_trigger_atomic) {
+        using Equeue = equeue<int, 8, true>;
+        bool flag{};
+
+        Equeue e1(Equeue::size_match::GE, 1, [&](){ flag = true; });
+
+        flag = false;
+        e1.clear_trigger();
+        EXPECT_EQ (false, flag);
+        e1.push_back(1);            // 1,  no-trigger cleared
+        EXPECT_EQ (false, flag);
+
+        flag = false;
+        e1.clear();
+        e1.clear_trigger();
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e1.push_back(1);            // 1
+        e1.push_back(2);            // 2
+        e1.set_trigger(Equeue::size_match::GE, 1, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e1.check_trigger();         // manual trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        e1.check_trigger();         // manual trigger attempt
+        EXPECT_EQ (false, flag);    // [SIZE triggers are auto clear]
+
+        Equeue e2(Equeue::data_match::MATCH_PUSH, 42, [&](){ flag = true; });
+        flag = false;
+        e2.clear_trigger();
+        EXPECT_EQ (false, flag);
+        e2.push_back(42);           // push 42, no-trigger cleared
+        EXPECT_EQ (false, flag);
+        e2.set_trigger(Equeue::data_match::MATCH_PUSH, 42, [&](){ flag = true; });
+        EXPECT_EQ (false, flag);    // no spurious triggers
+        e2.push_back(42);           // push 42, trigger
+        EXPECT_EQ (true, flag);
+
+        flag = false;
+        e2.push_back(42);           // push 42, re-trigger [DATA re-triggers]
+        EXPECT_EQ (true, flag);
+    }
+
+    // stream push-pop
+    TEST(Tequeue, stream_push_pop_atomic) {
+        equeue<int, 8, true> q1;
+
+        q1 << 1 << 2 << 3 << 4 << 5 << 6 << 7 << 8;
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q1.size());
+        EXPECT_EQ (false, q1.empty());
+        EXPECT_EQ (true, q1.full());
+
+        q1 << 9;                        // try to insert in full queue
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q1.size());
+        EXPECT_EQ (false, q1.empty());
+        EXPECT_EQ (true, q1.full());
+
+        int check_it=1;
+        for (auto it = q1.begin() ; it != q1.end() ; ++it)
+            EXPECT_EQ(*it, check_it++);
+        EXPECT_EQ(9, check_it);         // run through all
+
+        for (int i =1 ; i <= 8 ; ++i) {
+            check_it << q1;
+            EXPECT_EQ(i, check_it);
+        }
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (0UL, q1.size());
+        EXPECT_EQ (true, q1.empty());
+        EXPECT_EQ (false, q1.full());
+
+        q1 >> check_it;
+        EXPECT_EQ (int{}, check_it);
+    }
+
+}
diff --git a/test/tests/queue.cpp b/test/tests/queue.cpp
new file mode 100644
index 0000000..1452d68
--- /dev/null
+++ b/test/tests/queue.cpp
@@ -0,0 +1,188 @@
+/*!
+ * \file queue.cpp
+ * \brief
+ *      Unit tests for queue
+ *
+ * \copyright Copyright (C) 2020 Christos Choutouridis <christos@choutouridis.net>
+ *
+ * <dl class=\"section copyright\"><dt>License</dt><dd>
+ * The MIT License (MIT)
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ * </dd></dl>
+ *
+ */
+#include <utl/container/queue.h>
+#include <gtest/gtest.h>
+
+namespace Tqueue {
+    using namespace utl;
+
+
+    // Test construction
+    TEST(Tqueue, contruct) {
+        queue<int, 8> q1;
+        queue<int, 8> q2{1, 2, 3, 4, 5, 6, 7, 8};
+        queue<int, 8> q3{1, 2, 3, 4, 5};
+
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (0UL, q1.size());
+        EXPECT_EQ (8UL, q2.capacity());
+        EXPECT_EQ (8UL, q2.size());
+        EXPECT_EQ (8UL, q3.capacity());
+        EXPECT_EQ (5UL, q3.size());
+    }
+
+    // base class functionality check
+    TEST(Tqueue, base_class) {
+
+        queue<int, 8> q1;
+
+        // Access of base class functionality
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (0UL, q1.size());
+        EXPECT_EQ (true, q1.empty());
+        EXPECT_EQ (false, q1.full());
+
+        q1.push(42);
+        EXPECT_EQ (42, q1.front());
+        EXPECT_EQ (42, q1.back());
+        EXPECT_EQ (42, q1.pop());
+
+        q1.push(1);
+        q1.push(2);
+        q1.push(3);
+
+        int check_it=1;
+        for (auto it = q1.begin() ; it != q1.end() ; ++it)
+            EXPECT_EQ(*it, check_it++);
+        EXPECT_EQ(4, check_it);         // run through all
+    }
+
+    // stream push-pop
+    TEST(Tqueue, stream_push_pop) {
+        queue<int, 8> q1;
+
+        q1 << 1 << 2 << 3 << 4 << 5 << 6 << 7 << 8;
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q1.size());
+        EXPECT_EQ (false, q1.empty());
+        EXPECT_EQ (true, q1.full());
+
+        q1 << 9;                        // try to insert in full queue
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (8UL, q1.size());
+        EXPECT_EQ (false, q1.empty());
+        EXPECT_EQ (true, q1.full());
+
+        int check_it=1;
+        for (auto it = q1.begin() ; it != q1.end() ; ++it)
+            EXPECT_EQ(*it, check_it++);
+        EXPECT_EQ(9, check_it);         // run through all
+
+        for (int i =1 ; i <= 8 ; ++i) {
+            check_it << q1;
+            EXPECT_EQ(i, check_it);
+        }
+        EXPECT_EQ (8UL, q1.capacity());
+        EXPECT_EQ (0UL, q1.size());
+        EXPECT_EQ (true, q1.empty());
+        EXPECT_EQ (false, q1.full());
+
+        q1 >> check_it;
+        EXPECT_EQ (int{}, check_it);
+    }
+
+
+
+    // Test construction
+     TEST(Tqueue, contruct_atomic) {
+         queue<int, 8, true> q1;
+         queue<int, 8, true> q2{1, 2, 3, 4, 5, 6, 7, 8};
+         queue<int, 8, true> q3{1, 2, 3, 4, 5};
+
+         EXPECT_EQ (8UL, q1.capacity());
+         EXPECT_EQ (0UL, q1.size());
+         EXPECT_EQ (8UL, q2.capacity());
+         EXPECT_EQ (8UL, q2.size());
+         EXPECT_EQ (8UL, q3.capacity());
+         EXPECT_EQ (5UL, q3.size());
+     }
+
+     // base class functionality check
+     TEST(Tqueue, base_class_atomic) {
+
+         queue<int, 8, true> q1;
+
+         // Access of base class functionality
+         EXPECT_EQ (8UL, q1.capacity());
+         EXPECT_EQ (0UL, q1.size());
+         EXPECT_EQ (true, q1.empty());
+         EXPECT_EQ (false, q1.full());
+
+         q1.push(42);
+         EXPECT_EQ (42, q1.front());
+         EXPECT_EQ (42, q1.back());
+         EXPECT_EQ (42, q1.pop());
+
+         q1.push(1);
+         q1.push(2);
+         q1.push(3);
+
+         int check_it=1;
+         for (auto it = q1.begin() ; it != q1.end() ; ++it)
+             EXPECT_EQ(*it, check_it++);
+         EXPECT_EQ(4, check_it);         // run through all
+     }
+
+     // stream push-pop
+     TEST(Tqueue, stream_push_pop_atomic) {
+         queue<int, 8, true> q1;
+
+         q1 << 1 << 2 << 3 << 4 << 5 << 6 << 7 << 8;
+         EXPECT_EQ (8UL, q1.capacity());
+         EXPECT_EQ (8UL, q1.size());
+         EXPECT_EQ (false, q1.empty());
+         EXPECT_EQ (true, q1.full());
+
+         q1 << 9;                        // try to insert in full queue
+         EXPECT_EQ (8UL, q1.capacity());
+         EXPECT_EQ (8UL, q1.size());
+         EXPECT_EQ (false, q1.empty());
+         EXPECT_EQ (true, q1.full());
+
+         int check_it=1;
+         for (auto it = q1.begin() ; it != q1.end() ; ++it)
+             EXPECT_EQ(*it, check_it++);
+         EXPECT_EQ(9, check_it);         // run through all
+
+         for (int i =1 ; i <= 8 ; ++i) {
+             check_it << q1;
+             EXPECT_EQ(i, check_it);
+         }
+         EXPECT_EQ (8UL, q1.capacity());
+         EXPECT_EQ (0UL, q1.size());
+         EXPECT_EQ (true, q1.empty());
+         EXPECT_EQ (false, q1.full());
+
+         q1 >> check_it;
+         EXPECT_EQ (int{}, check_it);
+     }
+
+}