diff --git a/CMakeLists.txt b/CMakeLists.txt
index 44e8243..3fcb1f5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -31,4 +31,5 @@ add_subdirectory(
 add_subdirectory("core-buffer")
 add_subdirectory("sf-buffer")
 add_subdirectory("sf-stream")
-add_subdirectory("sf-writer")
\ No newline at end of file
+add_subdirectory("sf-writer")
+add_subdirectory("jf-live-writer")
\ No newline at end of file
diff --git a/jf-live-writer/CMakeLists.txt b/jf-live-writer/CMakeLists.txt
new file mode 100644
index 0000000..6028bfe
--- /dev/null
+++ b/jf-live-writer/CMakeLists.txt
@@ -0,0 +1,22 @@
+file(GLOB SOURCES
+        src/*.cpp)
+
+add_library(jf-live-writer-lib STATIC ${SOURCES})
+target_include_directories(jf-live-writer-lib PUBLIC include/)
+target_link_libraries(jf-live-writer-lib
+        external
+        core-buffer-lib)
+
+add_executable(jf-live-writer src/main.cpp)
+set_target_properties(jf-live-writer PROPERTIES OUTPUT_NAME jf_live_writer)
+target_link_libraries(jf-live-writer
+        jf-live-writer-lib
+        sf-writer-lib
+        hdf5
+        hdf5_hl
+        hdf5_cpp
+        pthread
+        )
+
+enable_testing()
+add_subdirectory(test/)
\ No newline at end of file
diff --git a/jf-live-writer/src/main.cpp b/jf-live-writer/src/main.cpp
new file mode 100644
index 0000000..7a73af7
--- /dev/null
+++ b/jf-live-writer/src/main.cpp
@@ -0,0 +1,158 @@
+#include <iostream>
+#include <string>
+#include <thread>
+#include <chrono>
+#include <vector>
+
+#include "date.h"
+#include "zmq.h"
+#include "writer_config.hpp"
+#include "buffer_config.hpp"
+#include "bitshuffle/bitshuffle.h"
+#include "JFH5Writer.hpp"
+#include "ImageAssembler.hpp"
+#include "BufferBinaryReader.hpp"
+
+using namespace std;
+using namespace chrono;
+using namespace writer_config;
+using namespace buffer_config;
+
+void read_buffer(
+        const string device,
+        const string channel_name,
+        const int i_module,
+        const vector<uint64_t>& buffer_blocks,
+        ImageAssembler& image_assembler)
+{
+    BufferBinaryReader block_reader(device, channel_name);
+    auto block_buffer = new BufferBinaryBlock();
+
+    for (uint64_t block_id:buffer_blocks) {
+
+        while(!image_assembler.is_slot_free(block_id)) {
+            this_thread::sleep_for(chrono::milliseconds(ASSEMBLER_RETRY_MS));
+        }
+
+        auto start_time = steady_clock::now();
+
+        block_reader.get_block(block_id, block_buffer);
+
+        auto end_time = steady_clock::now();
+        uint64_t read_us_duration = duration_cast<microseconds>(
+                end_time-start_time).count();
+
+        start_time = steady_clock::now();
+
+        image_assembler.process(block_id, i_module, block_buffer);
+
+        end_time = steady_clock::now();
+        uint64_t compose_us_duration = duration_cast<microseconds>(
+                end_time-start_time).count();
+
+        cout << "sf_writer:avg_read_us ";
+        cout << read_us_duration / BUFFER_BLOCK_SIZE << endl;
+        cout << "sf_writer:avg_assemble_us ";
+        cout << compose_us_duration / BUFFER_BLOCK_SIZE << endl;
+    }
+
+    delete block_buffer;
+}
+
+int main (int argc, char *argv[])
+{
+    if (argc != 7) {
+        cout << endl;
+        cout << "Usage: sf_writer [output_file] [device] [n_modules]";
+        cout << " [start_pulse_id] [stop_pulse_id] [pulse_id_step]";
+        cout << endl;
+        cout << "\toutput_file: Complete path to the output file." << endl;
+        cout << "\tdevice: Name of detector." << endl;
+        cout << "\tn_modules: number of modules" << endl;
+        cout << "\tstart_pulse_id: Start pulse_id of retrieval." << endl;
+        cout << "\tstop_pulse_id: Stop pulse_id of retrieval." << endl;
+        cout << "\tpulse_id_step: 1==100Hz, 2==50hz, 4==25Hz.." << endl;
+        cout << endl;
+
+        exit(-1);
+    }
+
+    string output_file = string(argv[1]);
+    const string device = string(argv[2]);
+    size_t n_modules = atoi(argv[3]);
+    uint64_t start_pulse_id = (uint64_t) atoll(argv[4]);
+    uint64_t stop_pulse_id = (uint64_t) atoll(argv[5]);
+    int pulse_id_step = atoi(argv[6]);
+
+    // Align start (up) and stop(down) pulse_id with pulse_id_step.
+    if (start_pulse_id % pulse_id_step != 0) {
+        start_pulse_id += pulse_id_step - (start_pulse_id % pulse_id_step);
+    }
+    if (stop_pulse_id % pulse_id_step != 0) {
+        stop_pulse_id -= (start_pulse_id % pulse_id_step);
+    }
+
+    uint64_t start_block = start_pulse_id / BUFFER_BLOCK_SIZE;
+    uint64_t stop_block = stop_pulse_id / BUFFER_BLOCK_SIZE;
+
+    // Generate list of buffer blocks that need to be loaded.
+    std::vector<uint64_t> buffer_blocks;
+    for (uint64_t i_block=start_block; i_block <= stop_block; i_block++) {
+        buffer_blocks.push_back(i_block);
+    }
+
+    ImageAssembler image_assembler(n_modules);
+
+    std::vector<std::thread> reading_threads(n_modules);
+    for (size_t i_module=0; i_module<n_modules; i_module++) {
+
+        // TODO: Very ugly. Fix.
+        string channel_name = "M";
+        if (i_module < 10) {
+            channel_name += "0";
+        }
+        channel_name += to_string(i_module);
+
+        reading_threads.emplace_back(
+                read_buffer,
+                device,
+                channel_name,
+                i_module,
+                ref(buffer_blocks),
+                ref(image_assembler));
+    }
+
+    JFH5Writer writer(output_file, device, n_modules,
+                      start_pulse_id, stop_pulse_id, pulse_id_step);
+
+    for (uint64_t block_id:buffer_blocks) {
+
+        while(!image_assembler.is_slot_full(block_id)) {
+            this_thread::sleep_for(chrono::milliseconds(ASSEMBLER_RETRY_MS));
+        }
+
+        auto metadata = image_assembler.get_metadata_buffer(block_id);
+        auto data = image_assembler.get_data_buffer(block_id);
+
+        auto start_time = steady_clock::now();
+
+        writer.write(metadata, data);
+
+        auto end_time = steady_clock::now();
+        auto write_us_duration = duration_cast<microseconds>(
+                end_time-start_time).count();
+
+        image_assembler.free_slot(block_id);
+
+        cout << "sf_writer:avg_write_us ";
+        cout << write_us_duration / BUFFER_BLOCK_SIZE << endl;
+    }
+
+    for (auto& reading_thread : reading_threads) {
+        if (reading_thread.joinable()) {
+            reading_thread.join();
+        }
+    }
+
+    return 0;
+}
diff --git a/jf-live-writer/test/CMakeLists.txt b/jf-live-writer/test/CMakeLists.txt
new file mode 100644
index 0000000..1079fc2
--- /dev/null
+++ b/jf-live-writer/test/CMakeLists.txt
@@ -0,0 +1,10 @@
+add_executable(jf-live-writer-tests main.cpp)
+
+target_link_libraries(jf-live-writer-tests
+        jf-live-writer-lib
+        hdf5
+        hdf5_hl
+        hdf5_cpp
+        zmq
+        gtest
+        )
diff --git a/jf-live-writer/test/main.cpp b/jf-live-writer/test/main.cpp
new file mode 100644
index 0000000..e819294
--- /dev/null
+++ b/jf-live-writer/test/main.cpp
@@ -0,0 +1,8 @@
+#include "gtest/gtest.h"
+
+using namespace std;
+
+int main(int argc, char **argv) {
+  ::testing::InitGoogleTest(&argc, argv);
+  return RUN_ALL_TESTS();
+}