diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 34281ac68..c0f3e3f32 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -127,6 +127,9 @@ target_link_libraries(TestFluidTensorDeath PRIVATE
 add_test_executable(TestFluidTensorView data/TestFluidTensorView.cpp)
 add_test_executable(TestFluidTensorSupport data/TestFluidTensorSupport.cpp)
 add_test_executable(TestFluidDataSet data/TestFluidDataSet.cpp)
+add_test_executable(TestFluidSource clients/common/TestFluidSource.cpp)
+add_test_executable(TestFluidSink clients/common/TestFluidSink.cpp)
+add_test_executable(TestBufferedProcess clients/common/TestBufferedProcess.cpp)
 
 include(CTest)
 include(Catch)
@@ -142,4 +145,8 @@ catch_discover_tests(TestFluidTensorView WORKING_DIRECTORY "${CMAKE_BINARY_DIR}"
 catch_discover_tests(TestFluidTensorSupport WORKING_DIRECTORY "${CMAKE_BINARY_DIR}")
 catch_discover_tests(TestFluidDataSet WORKING_DIRECTORY "${CMAKE_BINARY_DIR}")
 
+catch_discover_tests(TestFluidSource WORKING_DIRECTORY "${CMAKE_BINARY_DIR}")
+catch_discover_tests(TestFluidSink WORKING_DIRECTORY "${CMAKE_BINARY_DIR}")
+catch_discover_tests(TestBufferedProcess WORKING_DIRECTORY "${CMAKE_BINARY_DIR}")
+
 add_compile_tests("FluidTensor Compilation Tests" data/compile_tests/TestFluidTensor_Compile.cpp) 
diff --git a/tests/clients/common/TestBufferedProcess.cpp b/tests/clients/common/TestBufferedProcess.cpp
new file mode 100644
index 000000000..d91d6c40d
--- /dev/null
+++ b/tests/clients/common/TestBufferedProcess.cpp
@@ -0,0 +1,72 @@
+#define CATCH_CONFIG_MAIN
+#include <catch2/catch.hpp>
+// #include <catch2/catch_test_macros.hpp>
+#include <clients/common/BufferedProcess.hpp>
+#include <clients/common/FluidContext.hpp>
+#include <data/FluidTensor.hpp>
+#include <CatchUtils.hpp>
+#include <cmath> 
+#include <algorithm>
+#include <array>
+#include <vector>
+
+using fluid::EqualsRange;
+using fluid::FluidTensor;
+using fluid::FluidTensorView;
+using fluid::Slice;
+using fluid::client::BufferedProcess; 
+using fluid::client::FluidContext;
+
+TEST_CASE("BufferedProcess will reconstruct windowed input properly under COLA conditions","[BufferedProcess]"){
+    
+    BufferedProcess processor; 
+    
+    constexpr int hostSize = 64;
+    FluidContext c;
+    
+    auto frameSize = GENERATE(32, 64, 256, 1024, 8192);
+    
+    auto hop = frameSize / 2; 
+    
+    processor.maxSize(frameSize, frameSize, 1,1 ); 
+    processor.hostSize(hostSize); // sigh, FIXME
+    
+    FluidTensor<double,2> input(1,128 * frameSize);
+    
+    input(Slice(0),Slice(frameSize)).fill(1);
+    
+    FluidTensor<double,2> output(1,hostSize);
+    FluidTensor<double, 2> window(1, frameSize);
+    
+    std::vector<double> expected(hostSize);
+    std::vector<double> actual(hostSize);
+    
+    window.apply([frameSize, i=0](double& x) mutable { 
+        x = 0.5 - 0.5 * cos((2 * M_PI * i++) / frameSize);
+    }); //generate Hann window
+    
+    for(int i = frameSize; i < input.size() - hostSize;  i+=hostSize)
+    {
+      processor.push(input(Slice(0),Slice(i,hostSize)));
+      
+      //Hann windowing with overlap of 2 should be COLA
+      processor.process(frameSize, frameSize,hop,c,
+      [&window](FluidTensorView<double, 2> in, FluidTensorView<double, 2> out) {
+        out = in;
+        out.apply(window, [](double& x, double w) { x *= w; });
+      });
+
+      processor.pull(FluidTensorView<double,2>(actual.data(),0,1,hostSize));
+      
+      //we expect output to be input delayed by frameSize samples
+      auto expectedSlice= input(Slice(0), Slice(i - frameSize, hostSize));
+      std::copy(expectedSlice.begin(), expectedSlice.end(),expected.begin());
+      
+      auto matcher = Catch::Matchers::Approx(expected);
+      double epsilon = 1e-12;
+      matcher.epsilon(epsilon);
+      
+      CHECK_THAT(actual,matcher);
+      
+    }
+}
diff --git a/tests/clients/common/TestFluidSink.cpp b/tests/clients/common/TestFluidSink.cpp
new file mode 100644
index 000000000..096353d29
--- /dev/null
+++ b/tests/clients/common/TestFluidSink.cpp
@@ -0,0 +1,74 @@
+#define CATCH_CONFIG_MAIN
+#include <catch2/catch.hpp>
+// #include <catch2/catch_test_macros.hpp>
+#include <clients/common/FluidSink.hpp>
+#include <data/FluidTensor.hpp>
+#include <CatchUtils.hpp>
+#include <algorithm>
+#include <array>
+#include <vector>
+
+using fluid::EqualsRange;
+using fluid::FluidSink;
+using fluid::FluidTensor;
+using fluid::FluidTensorView;
+using fluid::Slice;
+
+
+TEMPLATE_TEST_CASE("FluidSink can overlap-add a varitety of window sizes and hops",
+    "[FluidSink][frames]", int, double)
+{
+
+  constexpr int hostSize = 64;
+  constexpr int maxFrameSize = 1024;
+
+  FluidSink<TestType> olaBuffer(maxFrameSize, 1);
+  olaBuffer.setHostBufferSize(hostSize);
+  olaBuffer.reset(1); // sigh, FIXME
+
+  std::array<TestType, 2 * maxFrameSize> data;
+  data.fill(1); 
+  
+  
+  std::array<TestType, maxFrameSize>     emptyFrame;
+
+  emptyFrame.fill(0);
+//  std::iota(data.begin(), data.end(), 0);
+
+  // run the test with each of these frame sizes
+  auto frameSize = GENERATE(32, 43, 64, 96, 128, 512);
+
+  FluidTensor<TestType, 1> expected(data.size());
+  expected.fill(0);
+  FluidTensor<TestType, 2> output(1, hostSize);
+
+
+  // and for each frame size above, we test with these overlaps
+  auto overlap = GENERATE(1,2,3,4);
+  
+  int hop = frameSize / overlap;
+  
+  //simulate ouptut data by building buffer for whole span
+  for(int i = 0; i < expected.size();i+=hop)
+  {
+    int chunkSize = std::min<int>(frameSize, expected.size() - i);
+    expected(Slice(i,chunkSize)).apply([](TestType& x){
+      x += 1;
+    });
+  }
+  
+
+  for (int i = 0, j = 0, k = 0; i < data.size() - hostSize; i += hostSize)
+  {
+    
+    for (; j < hostSize; j += hop, k += 1)
+    {
+      auto input = FluidTensorView<TestType, 2>{ data.data(), i, 1, frameSize };
+      olaBuffer.push(input, j);
+    }
+   
+    j = j < hostSize ? j : j - hostSize;
+    olaBuffer.pull(FluidTensorView<TestType,2>(output));
+    CHECK_THAT(output,EqualsRange(expected(Slice(i,hostSize))));
+  }
+}
diff --git a/tests/clients/common/TestFluidSource.cpp b/tests/clients/common/TestFluidSource.cpp
new file mode 100644
index 000000000..1e59e360d
--- /dev/null
+++ b/tests/clients/common/TestFluidSource.cpp
@@ -0,0 +1,63 @@
+#define CATCH_CONFIG_MAIN
+#include <catch2/catch.hpp>
+// #include <catch2/catch_test_macros.hpp>
+#include <clients/common/FluidSource.hpp>
+#include <data/FluidTensor.hpp>
+#include <CatchUtils.hpp>
+#include <algorithm>
+#include <array>
+#include <vector>
+
+using fluid::EqualsRange;
+using fluid::FluidSource;
+using fluid::FluidTensor;
+using fluid::FluidTensorView;
+using fluid::Slice;
+
+TEMPLATE_TEST_CASE(
+    "FluidSource can provide different window and hop sizes with a known delay",
+    "[FluidSource][frames]", int, double)
+{
+
+  constexpr int hostSize = 64;
+  constexpr int maxFrameSize = 1024;
+
+  FluidSource<TestType> framer(maxFrameSize, 1);
+  framer.setHostBufferSize(hostSize);
+  framer.reset(1); // sigh, FIXME
+
+  std::array<TestType, 2 * maxFrameSize> data;
+  std::array<TestType, maxFrameSize>     output;
+//  std::array<TestType, maxFrameSize>     emptyFrame;
+
+//  emptyFrame.fill(0);
+  std::iota(data.begin(), data.end(), 0);
+
+  // run the test with each of these frame sizes
+  auto frameSize = GENERATE(32, 43, 64, 96, 128, 512);
+
+  
+  // and for each frame size above, we test with these hops
+  auto hop = GENERATE_REF(int(frameSize / 4), int(frameSize / 3),
+                          int(frameSize / 2), int(frameSize));
+  
+
+  FluidTensor<TestType, 1> expected(data.size() + frameSize);
+  expected(Slice(frameSize)) = FluidTensorView<TestType,1>(data.data(),0,data.size());
+
+  for (int i = 0, j = 0, k = 0; i < data.size() - hostSize; i += hostSize)
+  {
+    auto input = FluidTensorView<TestType, 2>{ data.data(), i, 1, hostSize };
+    framer.push(input);
+    auto outputView = FluidTensorView<TestType, 2>{ output.data(), 0, 1, frameSize };
+
+
+    for (; j < hostSize; j += hop, k += hop)
+    {
+      framer.pull(outputView, j);
+      CHECK_THAT(outputView, EqualsRange(expected(Slice(k,frameSize))));
+    }
+
+    j = j < hostSize ? j : j - hostSize;
+  }
+}