diff --git a/src/backend/opencl/OclCache.cpp b/src/backend/opencl/OclCache.cpp
index f22fea72..d01eea06 100644
--- a/src/backend/opencl/OclCache.cpp
+++ b/src/backend/opencl/OclCache.cpp
@@ -63,7 +63,7 @@ static cl_program createFromSource(const IOclRunner *runner)
     if (OclLib::buildProgram(program, 1, &device, runner->buildOptions()) != CL_SUCCESS) {
         printf("BUILD LOG:\n%s\n", OclLib::getProgramBuildLog(program, device).data());
 
-        OclLib::releaseProgram(program);
+        OclLib::release(program);
         return nullptr;
     }
 
@@ -97,7 +97,7 @@ static cl_program createFromBinary(const IOclRunner *runner, const std::string &
     }
 
     if (OclLib::buildProgram(program, 1, &device) != CL_SUCCESS) {
-        OclLib::releaseProgram(program);
+        OclLib::release(program);
         return nullptr;
     }
 
diff --git a/src/backend/opencl/interfaces/IOclRunner.h b/src/backend/opencl/interfaces/IOclRunner.h
index ba4fa610..613244bf 100644
--- a/src/backend/opencl/interfaces/IOclRunner.h
+++ b/src/backend/opencl/interfaces/IOclRunner.h
@@ -55,6 +55,7 @@ public:
     virtual const char *source() const                      = 0;
     virtual const OclLaunchData &data() const               = 0;
     virtual size_t threadId() const                         = 0;
+    virtual uint32_t deviceIndex() const                    = 0;
     virtual void build()                                    = 0;
 
 protected:
diff --git a/src/backend/opencl/runners/OclBaseRunner.cpp b/src/backend/opencl/runners/OclBaseRunner.cpp
index 95d0c05a..ccbd4c48 100644
--- a/src/backend/opencl/runners/OclBaseRunner.cpp
+++ b/src/backend/opencl/runners/OclBaseRunner.cpp
@@ -66,11 +66,10 @@ xmrig::OclBaseRunner::OclBaseRunner(size_t id, const OclLaunchData &data) :
 
 xmrig::OclBaseRunner::~OclBaseRunner()
 {
-    OclLib::releaseProgram(m_program);
-    OclLib::releaseMemObject(m_input);
-    OclLib::releaseMemObject(m_output);
-
-    OclLib::releaseCommandQueue(m_queue);
+    OclLib::release(m_program);
+    OclLib::release(m_input);
+    OclLib::release(m_output);
+    OclLib::release(m_queue);
 }
 
 
@@ -86,6 +85,12 @@ bool xmrig::OclBaseRunner::selfTest() const
 }
 
 
+uint32_t xmrig::OclBaseRunner::deviceIndex() const
+{
+    return data().thread.index();
+}
+
+
 void xmrig::OclBaseRunner::build()
 {
     if (!isReadyToBuild()) {
diff --git a/src/backend/opencl/runners/OclBaseRunner.h b/src/backend/opencl/runners/OclBaseRunner.h
index 67703cbb..743c73fc 100644
--- a/src/backend/opencl/runners/OclBaseRunner.h
+++ b/src/backend/opencl/runners/OclBaseRunner.h
@@ -57,6 +57,7 @@ protected:
 
     bool isReadyToBuild() const override;
     bool selfTest() const override;
+    uint32_t deviceIndex() const override;
     void build() override;
 
 protected:
diff --git a/src/backend/opencl/runners/OclCnRunner.cpp b/src/backend/opencl/runners/OclCnRunner.cpp
index 28e9ba71..205bbda3 100644
--- a/src/backend/opencl/runners/OclCnRunner.cpp
+++ b/src/backend/opencl/runners/OclCnRunner.cpp
@@ -95,12 +95,17 @@ xmrig::OclCnRunner::~OclCnRunner()
     delete m_cn1;
     delete m_cn2;
 
-    OclLib::releaseMemObject(m_scratchpads);
-    OclLib::releaseMemObject(m_states);
+    OclLib::release(m_scratchpads);
+    OclLib::release(m_states);
 
     for (size_t i = 0; i < BRANCH_MAX; ++i) {
         delete m_branchKernels[i];
-        OclLib::releaseMemObject(m_branches[i]);
+        OclLib::release(m_branches[i]);
+    }
+
+    if (m_algorithm == Algorithm::CN_R) {
+        OclLib::release(m_cnr);
+        OclCnR::clear();
     }
 }
 
@@ -205,7 +210,8 @@ bool xmrig::OclCnRunner::set(const Job &job, uint8_t *blob)
         delete m_cn1;
 
         m_height = job.height();
-        m_cn1    = new Cn1Kernel(OclCnR::get(*this, m_height), m_height);
+        m_cnr    = OclCnR::get(*this, m_height);
+        m_cn1    = new Cn1Kernel(m_cnr, m_height);
     }
 
     if (!m_cn1->setArgs(m_input, m_scratchpads, m_states, intensity)) {
diff --git a/src/backend/opencl/runners/OclCnRunner.h b/src/backend/opencl/runners/OclCnRunner.h
index 28b19b60..1d28c41d 100644
--- a/src/backend/opencl/runners/OclCnRunner.h
+++ b/src/backend/opencl/runners/OclCnRunner.h
@@ -63,6 +63,7 @@ private:
 
     cl_mem m_scratchpads    = nullptr;
     cl_mem m_states         = nullptr;
+    cl_program m_cnr        = nullptr;
     Cn0Kernel *m_cn0        = nullptr;
     Cn1Kernel *m_cn1        = nullptr;
     Cn2Kernel *m_cn2        = nullptr;
diff --git a/src/backend/opencl/runners/tools/OclCnR.cpp b/src/backend/opencl/runners/tools/OclCnR.cpp
index a4f17574..ed415194 100644
--- a/src/backend/opencl/runners/tools/OclCnR.cpp
+++ b/src/backend/opencl/runners/tools/OclCnR.cpp
@@ -22,157 +22,286 @@
  *   along with this program. If not, see <http://www.gnu.org/licenses/>.
  */
 
-#include <cstring>
-#include <mutex>
-#include <regex>
-#include <sstream>
-#include <string>
-#include <thread>
-
+#include "backend/opencl/runners/tools/OclCnR.h"
 
 #include "backend/opencl/cl/cn/cryptonight_r_cl.h"
 #include "backend/opencl/interfaces/IOclRunner.h"
 #include "backend/opencl/OclCache.h"
 #include "backend/opencl/OclLaunchData.h"
 #include "backend/opencl/OclThread.h"
-#include "backend/opencl/runners/tools/OclCnR.h"
 #include "backend/opencl/wrappers/OclError.h"
 #include "backend/opencl/wrappers/OclLib.h"
 #include "base/io/log/Log.h"
+#include "base/tools/Baton.h"
 #include "base/tools/Chrono.h"
 #include "crypto/cn/CryptoNight_monero.h"
 
 
+#include <cstring>
+#include <mutex>
+#include <regex>
+#include <sstream>
+#include <string>
+#include <thread>
+#include <uv.h>
+
+
 namespace xmrig {
 
 
-static std::string getCode(const V4_Instruction *code, int code_size)
-{
-    std::stringstream s;
-
-    for (int i = 0; i < code_size; ++i) {
-        const V4_Instruction inst = code[i];
-
-        const uint32_t a = inst.dst_index;
-        const uint32_t b = inst.src_index;
-
-        switch (inst.opcode)
-        {
-        case MUL:
-            s << 'r' << a << "*=r" << b << ';';
-            break;
-
-        case ADD:
-            s << 'r' << a << "+=r" << b << '+' << inst.C << "U;";
-            break;
-
-        case SUB:
-            s << 'r' << a << "-=r" << b << ';';
-            break;
-
-        case ROR:
-        case ROL:
-            s << 'r' << a << "=rotate(r" << a << ((inst.opcode == ROR) ? ",ROT_BITS-r" : ",r") << b << ");";
-            break;
-
-        case XOR:
-            s << 'r' << a << "^=r" << b << ';';
-            break;
-        }
-
-        s << '\n';
-    }
-
-    return s.str();
-}
-
-
-class CacheEntry
+class CnrCacheEntry
 {
 public:
-    inline CacheEntry(const Algorithm &algorithm, uint64_t heightOffset, uint32_t deviceIndex, cl_program program) :
-        algorithm(algorithm),
+    inline CnrCacheEntry(const Algorithm &algo, uint64_t offset, uint32_t index, cl_program program) :
         program(program),
-        deviceIndex(deviceIndex),
-        heightOffset(heightOffset)
+        m_algo(algo),
+        m_index(index),
+        m_offset(offset)
     {}
 
-    const Algorithm algorithm;
-    const cl_program program;
-    const uint32_t deviceIndex;
-    const uint64_t heightOffset;
+    inline bool isExpired(uint64_t offset) const                                    { return m_offset + OclCnR::kHeightChunkSize < offset; }
+    inline bool match(const Algorithm &algo, uint64_t offset, uint32_t index) const { return m_algo == algo && m_offset == offset && m_index == index; }
+    inline bool match(const IOclRunner &runner, uint64_t offset) const              { return match(runner.algorithm(), offset, runner.deviceIndex()); }
+    inline void release()                                                           { OclLib::release(program); }
+
+    cl_program program;
+
+private:
+    const Algorithm m_algo;
+    const uint32_t m_index;
+    const uint64_t m_offset;
 };
 
 
-static std::mutex mutex;
-static std::vector<CacheEntry> cache;
-
-
-static cl_program search(const Algorithm &algorithm, uint64_t offset, uint32_t index)
+class CnrCache
 {
-    std::lock_guard<std::mutex> lock(mutex);
+public:
+    CnrCache() = default;
 
-    for (const CacheEntry &entry : cache) {
-        if (entry.heightOffset == offset && entry.deviceIndex == index && entry.algorithm == algorithm) {
-            return entry.program;
+    inline cl_program search(const IOclRunner &runner, uint64_t offset) { return search(runner.algorithm(), offset, runner.deviceIndex()); }
+
+
+    inline cl_program search(const Algorithm &algo, uint64_t offset, uint32_t index)
+    {
+        std::lock_guard<std::mutex> lock(m_mutex);
+
+        for (const auto &entry : m_data) {
+            if (entry.match(algo, offset, index)) {
+                return entry.program;
+            }
+        }
+
+        return nullptr;
+    }
+
+
+    void add(const Algorithm &algo, uint64_t offset, uint32_t index, cl_program program)
+    {
+        if (search(algo, offset, index)) {
+            OclLib::release(program);
+
+            return;
+        }
+
+        std::lock_guard<std::mutex> lock(m_mutex);
+
+        gc(offset);
+        m_data.emplace_back(algo, offset, index, program);
+    }
+
+
+    void clear()
+    {
+        std::lock_guard<std::mutex> lock(m_mutex);
+
+        for (auto &entry : m_data) {
+            entry.release();
+        }
+
+        m_data.clear();
+    }
+
+
+private:
+    void gc(uint64_t offset)
+    {
+        for (size_t i = 0; i < m_data.size();) {
+            const auto &entry = m_data[i];
+
+            if (entry.isExpired(offset)) {
+                m_data.back().release();
+                m_data.pop_back();
+            }
+            else {
+                ++i;
+            }
         }
     }
 
-    return nullptr;
-}
+
+    std::mutex m_mutex;
+    std::vector<CnrCacheEntry> m_data;
+};
 
 
-static inline cl_program search(const IOclRunner &runner, uint64_t offset) { return search(runner.algorithm(), offset, runner.data().thread.index()); }
+static CnrCache cache;
 
 
-cl_program build(const IOclRunner &runner, const std::string &source, uint64_t offset)
+class CnrBuilder
 {
-    std::lock_guard<std::mutex> lock(mutex);
+public:
+    CnrBuilder() = default;
 
-    cl_int ret;
-    cl_device_id device = runner.data().device.id();
-    const char *s       = source.c_str();
+    cl_program build(const IOclRunner &runner, uint64_t offset)
+    {
+    #   ifdef APP_DEBUG
+        const uint64_t ts = Chrono::steadyMSecs();
+    #   endif
 
-    cl_program program = OclLib::createProgramWithSource(runner.ctx(), 1, &s, nullptr, &ret);
-    if (ret != CL_SUCCESS) {
-        return nullptr;
+        std::lock_guard<std::mutex> lock(m_mutex);
+        cl_program program = cache.search(runner, offset);
+        if (program) {
+            return program;
+        }
+
+        cl_int ret;
+        const std::string source = getSource(offset);
+        cl_device_id device      = runner.data().device.id();
+        const char *s            = source.c_str();
+
+        program = OclLib::createProgramWithSource(runner.ctx(), 1, &s, nullptr, &ret);
+        if (ret != CL_SUCCESS) {
+            return nullptr;
+        }
+
+        if (OclLib::buildProgram(program, 1, &device, runner.buildOptions()) != CL_SUCCESS) {
+            printf("BUILD LOG:\n%s\n", OclLib::getProgramBuildLog(program, device).data());
+
+            OclLib::release(program);
+            return nullptr;
+        }
+
+        LOG_DEBUG(GREEN_BOLD("[ocl]") " programs for heights %" PRIu64 " - %" PRIu64 " compiled. (%" PRIu64 "ms)", offset, offset + OclCnR::kHeightChunkSize - 1, Chrono::steadyMSecs() - ts);
+
+        cache.add(runner.algorithm(), offset, runner.deviceIndex(), program);
+
+        return program;
     }
 
-    if (OclLib::buildProgram(program, 1, &device, runner.buildOptions()) != CL_SUCCESS) {
-        printf("BUILD LOG:\n%s\n", OclLib::getProgramBuildLog(program, device).data());
+private:
+    std::string getCode(const V4_Instruction *code, int code_size) const
+    {
+        std::stringstream s;
 
-        OclLib::releaseProgram(program);
-        return nullptr;
+        for (int i = 0; i < code_size; ++i) {
+            const V4_Instruction inst = code[i];
+
+            const uint32_t a = inst.dst_index;
+            const uint32_t b = inst.src_index;
+
+            switch (inst.opcode)
+            {
+            case MUL:
+                s << 'r' << a << "*=r" << b << ';';
+                break;
+
+            case ADD:
+                s << 'r' << a << "+=r" << b << '+' << inst.C << "U;";
+                break;
+
+            case SUB:
+                s << 'r' << a << "-=r" << b << ';';
+                break;
+
+            case ROR:
+            case ROL:
+                s << 'r' << a << "=rotate(r" << a << ((inst.opcode == ROR) ? ",ROT_BITS-r" : ",r") << b << ");";
+                break;
+
+            case XOR:
+                s << 'r' << a << "^=r" << b << ';';
+                break;
+            }
+
+            s << '\n';
+        }
+
+        return s.str();
     }
 
-    cache.emplace_back(runner.algorithm(), offset, runner.data().thread.index(), program);
 
-    return program;
-}
+    std::string getSource(uint64_t offset) const
+    {
+        std::string source(cryptonight_r_defines_cl);
+
+        for (size_t i = 0; i < OclCnR::kHeightChunkSize; ++i) {
+            V4_Instruction code[256];
+            const int code_size      = v4_random_math_init<Algorithm::CN_R>(code, offset + i);
+            const std::string kernel = std::regex_replace(cryptonight_r_cl, std::regex("XMRIG_INCLUDE_RANDOM_MATH"), getCode(code, code_size));
+
+            source += std::regex_replace(kernel, std::regex("KERNEL_NAME"), "cn1_" + std::to_string(offset + i));
+        }
+
+        return source;
+    }
+
+
+    std::mutex m_mutex;
+};
+
+
+class CnrBaton : public Baton<uv_work_t>
+{
+public:
+    inline CnrBaton(const IOclRunner &runner, uint64_t offset) :
+        runner(runner),
+        offset(offset)
+    {}
+
+    const IOclRunner &runner;
+    const uint64_t offset;
+};
+
+
+static CnrBuilder builder;
+static std::mutex bg_mutex;
 
 
 } // namespace xmrig
 
 
 
-cl_program xmrig::OclCnR::get(const IOclRunner &runner, uint64_t height, bool background)
+cl_program xmrig::OclCnR::get(const IOclRunner &runner, uint64_t height)
 {
     const uint64_t offset = (height / kHeightChunkSize) * kHeightChunkSize;
 
-    cl_program program = search(runner, offset);
+    if (offset + kHeightChunkSize - height == 1) {
+        auto baton = new CnrBaton(runner, offset + kHeightChunkSize);
+
+        uv_queue_work(uv_default_loop(), &baton->req,
+            [](uv_work_t *req) {
+                auto baton = static_cast<CnrBaton*>(req->data);
+
+                std::lock_guard<std::mutex> lock(bg_mutex);
+
+                builder.build(baton->runner, baton->offset);
+            },
+            [](uv_work_t *req, int) { delete static_cast<CnrBaton*>(req->data); }
+        );
+    }
+
+    cl_program program = cache.search(runner, offset);
     if (program) {
         return program;
     }
 
-    std::string source(cryptonight_r_defines_cl);
-
-    for (size_t i = 0; i < kHeightChunkSize; ++i) {
-        V4_Instruction code[256];
-        const int code_size      = v4_random_math_init<Algorithm::CN_R>(code, offset + i);
-        const std::string kernel = std::regex_replace(cryptonight_r_cl, std::regex("XMRIG_INCLUDE_RANDOM_MATH"), getCode(code, code_size));
-
-        source += std::regex_replace(kernel, std::regex("KERNEL_NAME"), "cn1_" + std::to_string(offset + i));
-    }
-
-    return build(runner, source, offset);;
+    return builder.build(runner, offset);;
+}
+
+
+void xmrig::OclCnR::clear()
+{
+    std::lock_guard<std::mutex> lock(bg_mutex);
+
+    cache.clear();
 }
diff --git a/src/backend/opencl/runners/tools/OclCnR.h b/src/backend/opencl/runners/tools/OclCnR.h
index dd575d0c..03db672f 100644
--- a/src/backend/opencl/runners/tools/OclCnR.h
+++ b/src/backend/opencl/runners/tools/OclCnR.h
@@ -42,10 +42,10 @@ class IOclRunner;
 class OclCnR
 {
 public:
-    constexpr static size_t kPrecompilationDepth = 1;
-    constexpr static size_t kHeightChunkSize     = 10;
+    constexpr static size_t kHeightChunkSize = 10;
 
-    static cl_program get(const IOclRunner &runner, uint64_t height, bool background = false);
+    static cl_program get(const IOclRunner &runner, uint64_t height);
+    static void clear();
 };
 
 
diff --git a/src/backend/opencl/wrappers/OclContext.cpp b/src/backend/opencl/wrappers/OclContext.cpp
index 04217f73..bc0f3de4 100644
--- a/src/backend/opencl/wrappers/OclContext.cpp
+++ b/src/backend/opencl/wrappers/OclContext.cpp
@@ -37,7 +37,7 @@ xmrig::OclContext::OclContext(const OclDevice &device)
 xmrig::OclContext::~OclContext()
 {
     if (m_ctx) {
-        OclLib::releaseContext(m_ctx);
+        OclLib::release(m_ctx);
     }
 }
 
diff --git a/src/backend/opencl/wrappers/OclKernel.cpp b/src/backend/opencl/wrappers/OclKernel.cpp
index 381a64d7..2da63458 100644
--- a/src/backend/opencl/wrappers/OclKernel.cpp
+++ b/src/backend/opencl/wrappers/OclKernel.cpp
@@ -39,7 +39,7 @@ xmrig::OclKernel::OclKernel(cl_program program, const char *name) :
 
 xmrig::OclKernel::~OclKernel()
 {
-    OclLib::releaseKernel(m_kernel);
+    OclLib::release(m_kernel);
 }
 
 
diff --git a/src/backend/opencl/wrappers/OclLib.cpp b/src/backend/opencl/wrappers/OclLib.cpp
index e2f6b065..0c9a4b38 100644
--- a/src/backend/opencl/wrappers/OclLib.cpp
+++ b/src/backend/opencl/wrappers/OclLib.cpp
@@ -375,7 +375,7 @@ cl_int xmrig::OclLib::getProgramInfo(cl_program program, cl_program_info param_n
 }
 
 
-cl_int xmrig::OclLib::releaseCommandQueue(cl_command_queue command_queue)
+cl_int xmrig::OclLib::release(cl_command_queue command_queue)
 {
     assert(pReleaseCommandQueue != nullptr);
     assert(pGetCommandQueueInfo != nullptr);
@@ -391,7 +391,7 @@ cl_int xmrig::OclLib::releaseCommandQueue(cl_command_queue command_queue)
 }
 
 
-cl_int xmrig::OclLib::releaseContext(cl_context context)
+cl_int xmrig::OclLib::release(cl_context context)
 {
     assert(pReleaseContext != nullptr);
 
@@ -404,7 +404,7 @@ cl_int xmrig::OclLib::releaseContext(cl_context context)
 }
 
 
-cl_int xmrig::OclLib::releaseKernel(cl_kernel kernel)
+cl_int xmrig::OclLib::release(cl_kernel kernel)
 {
     assert(pReleaseKernel != nullptr);
 
@@ -421,7 +421,7 @@ cl_int xmrig::OclLib::releaseKernel(cl_kernel kernel)
 }
 
 
-cl_int xmrig::OclLib::releaseMemObject(cl_mem mem_obj)
+cl_int xmrig::OclLib::release(cl_mem mem_obj)
 {
     assert(pReleaseMemObject != nullptr);
 
@@ -438,7 +438,7 @@ cl_int xmrig::OclLib::releaseMemObject(cl_mem mem_obj)
 }
 
 
-cl_int xmrig::OclLib::releaseProgram(cl_program program)
+cl_int xmrig::OclLib::release(cl_program program)
 {
     assert(pReleaseProgram != nullptr);
 
@@ -550,6 +550,15 @@ cl_uint xmrig::OclLib::getNumPlatforms()
 }
 
 
+cl_uint xmrig::OclLib::getReferenceCount(cl_program program)
+{
+    cl_uint out = 0;
+    OclLib::getProgramInfo(program, CL_PROGRAM_REFERENCE_COUNT, sizeof(cl_uint), &out);
+
+    return out;
+}
+
+
 cl_ulong xmrig::OclLib::getDeviceUlong(cl_device_id id, cl_device_info param, cl_ulong defaultValue)
 {
     OclLib::getDeviceInfo(id, param, sizeof(cl_ulong), &defaultValue);
diff --git a/src/backend/opencl/wrappers/OclLib.h b/src/backend/opencl/wrappers/OclLib.h
index 00b43705..aa85a4e6 100644
--- a/src/backend/opencl/wrappers/OclLib.h
+++ b/src/backend/opencl/wrappers/OclLib.h
@@ -60,11 +60,11 @@ public:
     static cl_int getPlatformInfo(cl_platform_id platform, cl_platform_info param_name, size_t param_value_size, void *param_value, size_t *param_value_size_ret);
     static cl_int getProgramBuildInfo(cl_program program, cl_device_id device, cl_program_build_info param_name, size_t param_value_size, void *param_value, size_t *param_value_size_ret);
     static cl_int getProgramInfo(cl_program program, cl_program_info param_name, size_t param_value_size, void *param_value, size_t *param_value_size_ret = nullptr);
-    static cl_int releaseCommandQueue(cl_command_queue command_queue);
-    static cl_int releaseContext(cl_context context);
-    static cl_int releaseKernel(cl_kernel kernel);
-    static cl_int releaseMemObject(cl_mem mem_obj);
-    static cl_int releaseProgram(cl_program program);
+    static cl_int release(cl_command_queue command_queue);
+    static cl_int release(cl_context context);
+    static cl_int release(cl_kernel kernel);
+    static cl_int release(cl_mem mem_obj);
+    static cl_int release(cl_program program);
     static cl_int setKernelArg(cl_kernel kernel, cl_uint arg_index, size_t arg_size, const void *arg_value);
     static cl_kernel createKernel(cl_program program, const char *kernel_name, cl_int *errcode_ret);
     static cl_mem createBuffer(cl_context context, cl_mem_flags flags, size_t size, void *host_ptr, cl_int *errcode_ret);
@@ -72,6 +72,7 @@ public:
     static cl_program createProgramWithSource(cl_context context, cl_uint count, const char **strings, const size_t *lengths, cl_int *errcode_ret);
     static cl_uint getDeviceUint(cl_device_id id, cl_device_info param, cl_uint defaultValue = 0);
     static cl_uint getNumPlatforms();
+    static cl_uint getReferenceCount(cl_program program);
     static cl_ulong getDeviceUlong(cl_device_id id, cl_device_info param, cl_ulong defaultValue = 0);
     static std::vector<cl_platform_id> getPlatformIDs();
     static String getDeviceString(cl_device_id id, cl_device_info param);
diff --git a/src/base/tools/String.cpp b/src/base/tools/String.cpp
index 363573c1..b11d6774 100644
--- a/src/base/tools/String.cpp
+++ b/src/base/tools/String.cpp
@@ -31,7 +31,6 @@
 
 
 xmrig::String::String(const char *str) :
-    m_data(nullptr),
     m_size(str == nullptr ? 0 : strlen(str))
 {
     if (m_size == 0) {
@@ -44,7 +43,6 @@ xmrig::String::String(const char *str) :
 
 
 xmrig::String::String(const char *str, size_t size) :
-    m_data(nullptr),
     m_size(size)
 {
     if (str == nullptr) {
@@ -60,7 +58,6 @@ xmrig::String::String(const char *str, size_t size) :
 
 
 xmrig::String::String(const String &other) :
-    m_data(nullptr),
     m_size(other.m_size)
 {
     if (other.m_data == nullptr) {
@@ -117,7 +114,7 @@ std::vector<xmrig::String> xmrig::String::split(char sep) const
     for (pos = 0; pos < m_size; ++pos) {
         if (m_data[pos] == sep) {
             if ((pos - start) > 0) {
-                out.push_back(String(m_data + start, pos - start));
+                out.emplace_back(m_data + start, pos - start);
             }
 
             start = pos + 1;
@@ -125,7 +122,7 @@ std::vector<xmrig::String> xmrig::String::split(char sep) const
     }
 
     if ((pos - start) > 0) {
-        out.push_back(String(m_data + start, pos - start));
+        out.emplace_back(m_data + start, pos - start);
     }
 
     return out;
diff --git a/src/base/tools/String.h b/src/base/tools/String.h
index 3e77b6da..0f365641 100644
--- a/src/base/tools/String.h
+++ b/src/base/tools/String.h
@@ -46,9 +46,9 @@ namespace xmrig {
 class String
 {
 public:
-    inline String() : m_data(nullptr), m_size(0)                                     {}
-    inline String(char *str) : m_data(str), m_size(str == nullptr ? 0 : strlen(str)) {}
-    inline String(String &&other) : m_data(other.m_data), m_size(other.m_size)       { other.m_data = nullptr; other.m_size = 0; }
+    inline String() = default;
+    inline String(char *str) : m_data(str), m_size(str == nullptr ? 0 : strlen(str))    {}
+    inline String(String &&other) noexcept : m_data(other.m_data), m_size(other.m_size) { other.m_data = nullptr; other.m_size = 0; }
 
     String(const char *str);
     String(const char *str, size_t size);
@@ -81,7 +81,7 @@ public:
     inline String &operator=(const char *str)          { copy(str); return *this; }
     inline String &operator=(const String &str)        { copy(str); return *this; }
     inline String &operator=(std::nullptr_t)           { delete [] m_data; m_data = nullptr; m_size = 0; return *this; }
-    inline String &operator=(String &&other)           { move(std::move(other)); return *this; }
+    inline String &operator=(String &&other) noexcept  { move(std::move(other)); return *this; }
 
     rapidjson::Value toJSON() const;
     rapidjson::Value toJSON(rapidjson::Document &doc) const;
@@ -97,8 +97,8 @@ private:
     void move(char *str);
     void move(String &&other);
 
-    char *m_data;
-    size_t m_size;
+    char *m_data    = nullptr;
+    size_t m_size   = 0;
 };
 
 
diff --git a/src/crypto/common/Algorithm.h b/src/crypto/common/Algorithm.h
index 97b6243b..93abb655 100644
--- a/src/crypto/common/Algorithm.h
+++ b/src/crypto/common/Algorithm.h
@@ -77,7 +77,7 @@ public:
         ARGON2
     };
 
-    inline Algorithm()                                     {}
+    inline Algorithm() = default;
     inline Algorithm(const char *algo) : m_id(parse(algo)) {}
     inline Algorithm(Id id) : m_id(id)                     {}
 
@@ -109,7 +109,7 @@ private:
 };
 
 
-typedef std::vector<Algorithm> Algorithms;
+using Algorithms = std::vector<Algorithm>;
 
 
 } /* namespace xmrig */
diff --git a/src/net/JobResults.cpp b/src/net/JobResults.cpp
index e7ab8706..7f4a56cb 100644
--- a/src/net/JobResults.cpp
+++ b/src/net/JobResults.cpp
@@ -43,8 +43,6 @@
 #   include "crypto/common/VirtualMemory.h"
 #endif
 
-#include "base/tools/Buffer.h"
-
 
 namespace xmrig {