diff --git a/tests/test.cpp b/tests/test.cpp
new file mode 100644
--- /dev/null
+++ b/tests/test.cpp
@@ -0,0 +1,359 @@
+/*
+  Copyright © 2018 Hasan Yavuz Özderya
+
+  This file is part of serialplot.
+
+  serialplot is free software: you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation, either version 3 of the License, or
+  (at your option) any later version.
+
+  serialplot is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with serialplot.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define CATCH_CONFIG_MAIN  // This tells Catch to provide a main() - only do this in one cpp file
+#include "catch.hpp"
+
+#include "samplepack.h"
+#include "source.h"
+#include "indexbuffer.h"
+#include "linindexbuffer.h"
+#include "ringbuffer.h"
+#include "readonlybuffer.h"
+
+#include "test_helpers.h"
+
+TEST_CASE("samplepack with no X", "[memory]")
+{
+    SamplePack pack(100, 3, false);
+
+    REQUIRE_FALSE(pack.hasX());
+    REQUIRE(pack.numChannels() == 3);
+    REQUIRE(pack.numSamples() == 100);
+
+    double* chan0 = pack.data(0);
+    double* chan1 = pack.data(1);
+    double* chan2 = pack.data(2);
+
+    REQUIRE(chan0 == chan1 - 100);
+    REQUIRE(chan1 == chan2 - 100);
+}
+
+TEST_CASE("samplepack with X", "[memory]")
+{
+    SamplePack pack(100, 3, true);
+
+    REQUIRE(pack.hasX());
+    REQUIRE(pack.numChannels() == 3);
+    REQUIRE(pack.numSamples() == 100);
+    REQUIRE(pack.xData() != nullptr);
+}
+
+TEST_CASE("sink", "[memory, stream]")
+{
+    TestSink sink;
+    SamplePack pack(100, 3, false);
+
+    sink.setNumChannels(3, false);
+    REQUIRE(sink.numChannels() == 3);
+
+    sink.feedIn(pack);
+    REQUIRE(sink.totalFed == 100);
+    sink.feedIn(pack);
+    REQUIRE(sink.totalFed == 200);
+
+    TestSink follower;
+
+    sink.connectFollower(&follower);
+    REQUIRE(follower.numChannels() == 3);
+    REQUIRE(follower.hasX() == false);
+
+    sink.feedIn(pack);
+    REQUIRE(sink.totalFed == 300);
+    REQUIRE(follower.totalFed == 100);
+
+    sink.setNumChannels(2, true);
+    REQUIRE(follower.numChannels() == 2);
+    REQUIRE(follower.hasX() == true);
+}
+
+TEST_CASE("sink must be created unconnected", "[memory, stream]")
+{
+    TestSink sink;
+    REQUIRE(sink.connectedSource() == NULL);
+}
+
+TEST_CASE("source", "[memory, stream]")
+{
+    TestSink sink;
+
+    TestSource source(3, false);
+
+    REQUIRE(source.numChannels() == 3);
+    REQUIRE(source.hasX() == false);
+
+    source.connectSink(&sink);
+    REQUIRE(sink.numChannels() == 3);
+    REQUIRE(sink.hasX() == false);
+
+    source._setNumChannels(5, true);
+    REQUIRE(sink.numChannels() == 5);
+    REQUIRE(sink.hasX() == true);
+
+    SamplePack pack(100, 5, true);
+    source._feed(pack);
+    REQUIRE(sink.totalFed == 100);
+
+    source.disconnect(&sink);
+    source._feed(pack);
+    REQUIRE(sink.totalFed == 100);
+}
+
+TEST_CASE("source must set/unset sink 'source'", "[memory, stream]")
+{
+    TestSink sink;
+    TestSource source(3, false);
+
+    source.connectSink(&sink);
+    REQUIRE(sink.connectedSource() == &source);
+
+    source.disconnect(&sink);
+    REQUIRE(sink.connectedSource() == NULL);
+}
+
+TEST_CASE("source disconnect all sinks", "[memory, stream]")
+{
+    TestSink sinks[3];
+    TestSource source(3, false);
+
+    // connect sinks
+    for (int i = 0; i < 3; i++)
+    {
+        source.connectSink(&sinks[i]);
+    }
+
+    source.disconnectSinks();
+    for (int i = 0; i < 3; i++)
+    {
+        REQUIRE(sinks[i].connectedSource() == NULL);
+    }
+}
+
+TEST_CASE("IndexBuffer", "[memory, buffer]")
+{
+    IndexBuffer buf(10);
+
+    REQUIRE(buf.size() == 10);
+    for (unsigned i = 0; i < 10; i++)
+    {
+        REQUIRE(buf.sample(i) == i);
+    }
+    auto l = buf.limits();
+    REQUIRE(l.start == 0);
+    REQUIRE(l.end == 9);
+
+    buf.resize(20);
+    REQUIRE(buf.size() == 20);
+    REQUIRE(buf.sample(15) == 15);
+    l = buf.limits();
+    REQUIRE(l.start == 0);
+    REQUIRE(l.end == 19);
+}
+
+TEST_CASE("LinIndexBuffer", "[memory, buffer]")
+{
+    LinIndexBuffer buf(10, 0., 3.0);
+
+    REQUIRE(buf.size() == 10);
+    REQUIRE(buf.sample(0) == 0.);
+    REQUIRE(buf.sample(9) == 3.0);
+    REQUIRE(buf.sample(4) == Approx(1+1/3.));
+
+    auto l = buf.limits();
+    REQUIRE(l.start == 0.);
+    REQUIRE(l.end == 3.);
+
+    buf.resize(20);
+    REQUIRE(buf.size() == 20);
+    REQUIRE(buf.sample(0) == 0.);
+    REQUIRE(buf.sample(9) == Approx(9.*3./19.));
+    REQUIRE(buf.sample(4) == Approx(4.*3./19.));
+    REQUIRE(buf.sample(19) == 3.0);
+
+    l = buf.limits();
+    REQUIRE(l.start == 0.);
+    REQUIRE(l.end == 3.0);
+
+    buf.setLimits({-5., 5.});
+    l = buf.limits();
+    REQUIRE(l.start == -5.0);
+    REQUIRE(l.end == 5.0);
+
+    REQUIRE(buf.sample(0) == -5.0);
+    REQUIRE(buf.sample(19) == 5.0);
+}
+
+TEST_CASE("RingBuffer sizing", "[memory, buffer]")
+{
+    RingBuffer buf(10);
+
+    REQUIRE(buf.size() == 10);
+
+    buf.resize(5);
+    REQUIRE(buf.size() == 5);
+
+    buf.resize(15);
+    REQUIRE(buf.size() == 15);
+}
+
+TEST_CASE("RingBuffer initial values should be 0", "[memory, buffer]")
+{
+    RingBuffer buf(10);
+
+    for (unsigned i = 0; i < 10; i++)
+    {
+        REQUIRE(buf.sample(i) == 0.);
+    }
+}
+
+TEST_CASE("RingBuffer data access", "[memory, buffer]")
+{
+    RingBuffer buf(10);
+    double values[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+
+    buf.addSamples(values, 10);
+
+    REQUIRE(buf.size() == 10);
+    for (unsigned i = 0; i < 10; i++)
+    {
+        REQUIRE(buf.sample(i) == values[i]);
+    }
+
+    buf.addSamples(values, 5);
+
+    REQUIRE(buf.size() == 10);
+    for (unsigned i = 0; i < 5; i++)
+    {
+        REQUIRE(buf.sample(i) == values[i+5]);
+    }
+    for (unsigned i = 5; i < 10; i++)
+    {
+        REQUIRE(buf.sample(i) == values[i-5]);
+    }
+}
+
+TEST_CASE("making RingBuffer bigger should keep end values", "[memory, buffer]")
+{
+    RingBuffer buf(5);
+    double values[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+
+    buf.addSamples(values, 5);
+    buf.resize(10);
+
+    REQUIRE(buf.size() == 10);
+    for (unsigned i = 0; i < 5; i++)
+    {
+        REQUIRE(buf.sample(i) == 0);
+    }
+    for (unsigned i = 5; i < 10; i++)
+    {
+        REQUIRE(buf.sample(i) == values[i-5]);
+    }
+}
+
+TEST_CASE("making RingBuffer smaller should keep end values", "[memory, buffer]")
+{
+    RingBuffer buf(10);
+    double values[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+
+    buf.addSamples(values, 10);
+    buf.resize(5);
+
+    REQUIRE(buf.size() == 5);
+    for (unsigned i = 0; i < 5; i++)
+    {
+        REQUIRE(buf.sample(i) == values[i+5]);
+    }
+}
+
+TEST_CASE("RingBuffer limits", "[memory, buffer]")
+{
+    RingBuffer buf(10);
+    double values[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+
+    auto lim = buf.limits();
+    REQUIRE(lim.start == 0.);
+    REQUIRE(lim.end == 0.);
+
+    buf.addSamples(values, 10);
+    lim = buf.limits();
+    REQUIRE(lim.start == 1.);
+    REQUIRE(lim.end == 10.);
+
+    buf.addSamples(&values[9], 1);
+    lim = buf.limits();
+    REQUIRE(lim.start == 2.);
+    REQUIRE(lim.end == 10.);
+
+    buf.addSamples(values, 9);
+    buf.addSamples(values, 1);
+    lim = buf.limits();
+    REQUIRE(lim.start == 1.);
+    REQUIRE(lim.end == 9.);
+}
+
+TEST_CASE("RingBuffer clear", "[memory, buffer]")
+{
+    RingBuffer buf(10);
+    double values[10] = {1, 2, 3, 4, 5, 6, 7, 8, 9, 10};
+
+    buf.addSamples(values, 10);
+    buf.clear();
+
+    REQUIRE(buf.size() == 10);
+    for (unsigned i = 0; i < 10; i++)
+    {
+        REQUIRE(buf.sample(i) == 0.);
+    }
+    auto lim = buf.limits();
+    REQUIRE(lim.start == 0.);
+    REQUIRE(lim.end == 0.);
+}
+
+TEST_CASE("ReadOnlyBuffer", "[memory, buffer]")
+{
+    IndexBuffer source(10);
+
+    ReadOnlyBuffer buf(&source);
+
+    REQUIRE(buf.size() == 10);
+    auto lim = buf.limits();
+    REQUIRE(lim.start == 0.);
+    REQUIRE(lim.end == 9.);
+    for (unsigned i = 0; i < 10; i++)
+    {
+        REQUIRE(buf.sample(i) == i);
+    }
+}
+
+TEST_CASE("ReadOnlyBuffer sliced constructor", "[memory, buffer]")
+{
+    IndexBuffer source(10);
+
+    ReadOnlyBuffer buf(&source, 5, 4);
+
+    REQUIRE(buf.size() == 4);
+    auto lim = buf.limits();
+    REQUIRE(lim.start == 5.);
+    REQUIRE(lim.end == 8.);
+    for (unsigned i = 0; i < 4; i++)
+    {
+        REQUIRE(buf.sample(i) == (i + 5));
+    }
+}