diff --git a/hdk/common/__init__.py b/hdk/common/__init__.py
index cd563aaf9..48c4420ae 100644
--- a/hdk/common/__init__.py
+++ b/hdk/common/__init__.py
@@ -1,2 +1,2 @@
 """HDK's module for shared data structures and code"""
-from . import data_types, representation
+from . import data_types, debugging, representation
diff --git a/hdk/common/debugging/__init__.py b/hdk/common/debugging/__init__.py
new file mode 100644
index 000000000..b18d821bf
--- /dev/null
+++ b/hdk/common/debugging/__init__.py
@@ -0,0 +1,2 @@
+"""HDK's module for debugging"""
+from .draw_graph import draw_graph
diff --git a/hdk/common/debugging/draw_graph.py b/hdk/common/debugging/draw_graph.py
new file mode 100644
index 000000000..46474d0b7
--- /dev/null
+++ b/hdk/common/debugging/draw_graph.py
@@ -0,0 +1,196 @@
+"""functions to draw the different graphs we can generate in the package, eg to debug"""
+from typing import Dict, List
+
+import matplotlib.pyplot as plt
+import networkx as nx
+
+from hdk.common.representation import intermediate as ir
+
+IR_NODE_COLOR_MAPPING = {ir.Input: "blue", ir.Add: "red", ir.Sub: "yellow", ir.Mul: "green"}
+
+
+def human_readable_layout(graph: nx.Graph, x_delta: float = 1.0, y_delta: float = 1.0) -> Dict:
+    """
+    Returns a pos to be used later with eg nx.draw_networkx_nodes, so that nodes
+    are ordered by depth from input along the x axis and have a uniform
+    distribution along the y axis
+
+    Args:
+        graph (nx.Graph): The graph that we want to draw
+        x_delta (float): Parameter used to set the increment in x
+        y_delta (float): Parameter used to set the increment in y
+
+    Returns:
+        pos (Dict): the argument to use with eg nx.draw_networkx_nodes
+
+    """
+
+    # FIXME: less variables
+    # pylint: disable=too-many-locals
+
+    nodes_depth = {node: 0 for node in graph.nodes()}
+    input_nodes = [node for node in graph.nodes() if len(list(graph.predecessors(node))) == 0]
+
+    # Init a layout so that unreachable nodes have a pos, avoids potential crashes wiht networkx
+    # use a cheap layout
+    pos = nx.random_layout(graph)
+
+    curr_x = 0.0
+    curr_y = -(len(input_nodes) - 1) / 2 * y_delta
+
+    for in_node in input_nodes:
+        pos[in_node] = (curr_x, curr_y)
+        curr_y += y_delta
+
+    curr_x += x_delta
+
+    curr_nodes = input_nodes
+
+    current_depth = 0
+    while len(curr_nodes) > 0:
+        current_depth += 1
+        next_nodes_set = set()
+        for node in curr_nodes:
+            next_nodes_set.update(graph.successors(node))
+
+        curr_nodes = list(next_nodes_set)
+        for node in curr_nodes:
+            nodes_depth[node] = current_depth
+
+    nodes_by_depth: Dict[int, List[int]] = {}
+    for node, depth in nodes_depth.items():
+        nodes_for_depth = nodes_by_depth.get(depth, [])
+        nodes_for_depth.append(node)
+        nodes_by_depth[depth] = nodes_for_depth
+
+    depths = sorted(nodes_by_depth.keys())
+
+    for depth in depths:
+        nodes_at_depth = nodes_by_depth[depth]
+
+        curr_y = -(len(nodes_at_depth) - 1) / 2 * y_delta
+        for node in nodes_at_depth:
+            pos[node] = (curr_x, curr_y)
+            curr_y += y_delta
+
+        curr_x += x_delta
+
+    # pylint: enable=too-many-locals
+    return pos
+
+
+def draw_graph(
+    graph: nx.DiGraph, block_until_user_closes_graph: bool = True, draw_edge_numbers: bool = True
+) -> None:
+    """
+    Draw a graph
+
+    Args:
+        graph (nx.DiGraph): The graph that we want to draw
+        block_until_user_closes_graph (bool): if True, will wait the user to
+            close the figure before continuing; False is useful for the CI tests
+        draw_edge_numbers (bool): if True, add the edge number on the arrow
+            linking nodes, eg to differentiate the x and y in a Sub coding
+            (x - y). This option is not that useful for commutative ops, and
+            may make the picture a bit too dense, so could be deactivated
+
+    Returns:
+        None
+
+    """
+
+    # FIXME: less variables
+    # pylint: disable=too-many-locals
+
+    # Positions of the node
+    pos = human_readable_layout(graph)
+
+    # Colors and labels
+    color_map = [IR_NODE_COLOR_MAPPING[type(node)] for node in graph.nodes()]
+
+    # For most types, we just pick the operation as the label, but for Input,
+    # we take the name of the variable, ie the argument name of the function
+    # to compile
+    label_dict = {
+        node: node.input_name if isinstance(node, ir.Input) else node.__class__.__name__
+        for node in graph.nodes()
+    }
+
+    # Draw nodes
+    nx.draw_networkx_nodes(
+        graph,
+        pos,
+        node_color=color_map,
+        node_size=1000,
+        alpha=1,
+    )
+
+    # Draw labels
+    nx.draw_networkx_labels(graph, pos, labels=label_dict)
+
+    current_axes = plt.gca()
+
+    # And draw edges in a way which works when we have two "equivalent edges",
+    # ie from the same node A to the same node B, like to represent y = x + x
+    already_done = set()
+
+    for e in graph.edges:
+
+        # If we already drew the different edges from e[0] to e[1], continue
+        if (e[0], e[1]) in already_done:
+            continue
+
+        already_done.add((e[0], e[1]))
+
+        edges = graph.get_edge_data(e[0], e[1])
+
+        # Draw the different edges from e[0] to e[1], continue
+        for which, edge in enumerate(edges.values()):
+            edge_index = edge["input_idx"]
+
+            # Draw the edge
+            current_axes.annotate(
+                "",
+                xy=pos[e[0]],
+                xycoords="data",
+                xytext=pos[e[1]],
+                textcoords="data",
+                arrowprops=dict(
+                    arrowstyle="<-",
+                    color="0.5",
+                    shrinkA=5,
+                    shrinkB=5,
+                    patchA=None,
+                    patchB=None,
+                    connectionstyle="arc3,rad=rrr".replace("rrr", str(0.3 * which)),
+                ),
+            )
+
+            if draw_edge_numbers:
+                # Print the number of the node on the edge. This is a bit artisanal,
+                # since it seems not possible to add the text directly on the
+                # previously drawn arrow. So, more or less, we try to put a text at
+                # a position which is close to pos[e[1]] and which varies a bit with
+                # 'which'
+                a, b = pos[e[0]]
+                c, d = pos[e[1]]
+                const_0 = 1
+                const_1 = 2
+
+                current_axes.annotate(
+                    str(edge_index),
+                    xycoords="data",
+                    xy=(
+                        (const_0 * a + const_1 * c) / (const_0 + const_1),
+                        (const_0 * b + const_1 * d + 0.1 * which) / (const_0 + const_1),
+                    ),
+                    textcoords="data",
+                )
+
+    plt.axis("off")
+
+    # block_until_user_closes_graph is used as True for real users and False
+    # for CI
+    plt.show(block=block_until_user_closes_graph)
+
+    # pylint: enable=too-many-locals
diff --git a/poetry.lock b/poetry.lock
index c0eb2c77b..2337759c8 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -821,7 +821,7 @@ testing = ["pytest (>=4.6)", "pytest-checkdocs (>=2.4)", "pytest-flake8", "pytes
 [metadata]
 lock-version = "1.1"
 python-versions = ">=3.7,<3.10"
-content-hash = "2dbebb6e1d3b5f35cd48891bb9ed49b9d57d1f5659419e27150c5a3786d4b054"
+content-hash = "e0f2368e94fc45bae93f9695b3702a12f4d2c013caaff22012e3abfc4f7af6ab"
 
 [metadata.files]
 alabaster = [
@@ -1199,6 +1199,11 @@ pathspec = [
     {file = "pathspec-0.8.1.tar.gz", hash = "sha256:86379d6b86d75816baba717e64b1a3a3469deb93bb76d613c9ce79edc5cb68fd"},
 ]
 pillow = [
+    {file = "Pillow-8.3.1-1-cp36-cp36m-win_amd64.whl", hash = "sha256:fd7eef578f5b2200d066db1b50c4aa66410786201669fb76d5238b007918fb24"},
+    {file = "Pillow-8.3.1-1-cp37-cp37m-win_amd64.whl", hash = "sha256:75e09042a3b39e0ea61ce37e941221313d51a9c26b8e54e12b3ececccb71718a"},
+    {file = "Pillow-8.3.1-1-cp38-cp38-win_amd64.whl", hash = "sha256:c0e0550a404c69aab1e04ae89cca3e2a042b56ab043f7f729d984bf73ed2a093"},
+    {file = "Pillow-8.3.1-1-cp39-cp39-win_amd64.whl", hash = "sha256:479ab11cbd69612acefa8286481f65c5dece2002ffaa4f9db62682379ca3bb77"},
+    {file = "Pillow-8.3.1-1-pp37-pypy37_pp73-win_amd64.whl", hash = "sha256:f156d6ecfc747ee111c167f8faf5f4953761b5e66e91a4e6767e548d0f80129c"},
     {file = "Pillow-8.3.1-cp36-cp36m-macosx_10_10_x86_64.whl", hash = "sha256:196560dba4da7a72c5e7085fccc5938ab4075fd37fe8b5468869724109812edd"},
     {file = "Pillow-8.3.1-cp36-cp36m-manylinux_2_17_aarch64.manylinux2014_aarch64.whl", hash = "sha256:29c9569049d04aaacd690573a0398dbd8e0bf0255684fee512b413c2142ab723"},
     {file = "Pillow-8.3.1-cp36-cp36m-manylinux_2_5_i686.manylinux1_i686.whl", hash = "sha256:c088a000dfdd88c184cc7271bfac8c5b82d9efa8637cd2b68183771e3cf56f04"},
diff --git a/pyproject.toml b/pyproject.toml
index 13c80cb78..0b1603c32 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -10,6 +10,7 @@ Sphinx = "^4.1.1"
 sphinx-rtd-theme = "^0.5.2"
 myst-parser = "^0.15.1"
 networkx = "^2.6.1"
+matplotlib = "^3.4.2"
 
 [tool.poetry.dev-dependencies]
 isort = "^5.9.2"
diff --git a/tests/hnumpy/test_debugging.py b/tests/hnumpy/test_debugging.py
new file mode 100644
index 000000000..2ade31562
--- /dev/null
+++ b/tests/hnumpy/test_debugging.py
@@ -0,0 +1,58 @@
+"""Test file for HDK's hnumpy debugging functions"""
+
+import pytest
+
+from hdk.common.data_types.integers import Integer
+from hdk.common.data_types.values import ClearValue, EncryptedValue
+from hdk.common.debugging import draw_graph
+from hdk.hnumpy import tracing
+
+
+@pytest.mark.parametrize(
+    "lambda_f",
+    [
+        lambda x, y: x + y,
+        lambda x, y: x + x - y * y * y + x,
+    ],
+)
+@pytest.mark.parametrize(
+    "x",
+    [
+        pytest.param(EncryptedValue(Integer(64, is_signed=False)), id="Encrypted uint"),
+        # pytest.param(
+        #     EncryptedValue(Integer(64, is_signed=True)),
+        #     id="Encrypted int",
+        # ),
+        # pytest.param(
+        #     ClearValue(Integer(64, is_signed=False)),
+        #     id="Clear uint",
+        # ),
+        # pytest.param(
+        #     ClearValue(Integer(64, is_signed=True)),
+        #     id="Clear int",
+        # ),
+    ],
+)
+@pytest.mark.parametrize(
+    "y",
+    [
+        pytest.param(EncryptedValue(Integer(64, is_signed=False)), id="Encrypted uint"),
+        # pytest.param(
+        #     EncryptedValue(Integer(64, is_signed=True)),
+        #     id="Encrypted int",
+        # ),
+        pytest.param(
+            ClearValue(Integer(64, is_signed=False)),
+            id="Clear uint",
+        ),
+        # pytest.param(
+        #     ClearValue(Integer(64, is_signed=True)),
+        #     id="Clear int",
+        # ),
+    ],
+)
+def test_hnumpy_draw_graph(lambda_f, x, y):
+    "Test hnumpy draw_graph"
+    graph = tracing.trace_numpy_function(lambda_f, {"x": x, "y": y})
+
+    draw_graph(graph, block_until_user_closes_graph=False)