diff --git a/docs/docker.rst b/docs/docker.rst
--- a/docs/docker.rst
+++ b/docs/docker.rst
@@ -73,3 +73,6 @@
 
     $ java -cp app/swh-graph.jar \
         org.softwareheritage.graph.App data/compressed/g
+
+To specify the port on which the server will run, use the `--port` or `-p` flag
+(default is 5009).
diff --git a/java/server/README.md b/java/server/README.md
--- a/java/server/README.md
+++ b/java/server/README.md
@@ -14,7 +14,7 @@
 --------------
 
 ```bash
-$ java -cp target/swh-graph-1.0-jar-with-dependencies.jar   \
+$ java -cp target/swh-graph-0.0.1-jar-with-dependencies.jar \
     org.softwareheritage.graph.App                          \
     <compressed_graph_path>
 ```
@@ -41,7 +41,7 @@
 
 $ mvn compile assembly:single
 # Dump mapping files
-$ java -cp target/swh-graph-1.0-jar-with-dependencies.jar   \
+$ java -cp target/swh-graph-0.0.1-jar-with-dependencies.jar \
     org.softwareheritage.graph.backend.Setup                \
     src/test/dataset/example.nodes.csv.gz                   \
     src/test/dataset/output/example
diff --git a/java/server/pom.xml b/java/server/pom.xml
--- a/java/server/pom.xml
+++ b/java/server/pom.xml
@@ -6,7 +6,7 @@
 
     <groupId>org.softwareheritage.graph</groupId>
     <artifactId>swh-graph</artifactId>
-    <version>1.0</version>
+    <version>0.0.1</version>
 
     <name>swh-graph</name>
     <url>https://www.softwareheritage.org/</url>
@@ -59,6 +59,11 @@
             <artifactId>fastutil</artifactId>
             <version>8.2.2</version>
         </dependency>
+        <dependency>
+            <groupId>com.martiansoftware</groupId>
+            <artifactId>jsap</artifactId>
+            <version>2.1</version>
+        </dependency>
     </dependencies>
 
     <build>
diff --git a/java/server/src/main/java/org/softwareheritage/graph/AllowedEdges.java b/java/server/src/main/java/org/softwareheritage/graph/AllowedEdges.java
--- a/java/server/src/main/java/org/softwareheritage/graph/AllowedEdges.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/AllowedEdges.java
@@ -9,8 +9,8 @@
  * Edge restriction based on node types, used when visiting the graph.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class AllowedEdges {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/App.java b/java/server/src/main/java/org/softwareheritage/graph/App.java
--- a/java/server/src/main/java/org/softwareheritage/graph/App.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/App.java
@@ -6,6 +6,13 @@
 
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.PropertyNamingStrategy;
+import com.martiansoftware.jsap.FlaggedOption;
+import com.martiansoftware.jsap.JSAP;
+import com.martiansoftware.jsap.JSAPException;
+import com.martiansoftware.jsap.JSAPResult;
+import com.martiansoftware.jsap.Parameter;
+import com.martiansoftware.jsap.SimpleJSAP;
+import com.martiansoftware.jsap.UnflaggedOption;
 import io.javalin.Javalin;
 import io.javalin.http.Context;
 import io.javalin.plugin.json.JavalinJackson;
@@ -19,15 +26,37 @@
  * Entrypoint of the swh-graph server REST API.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class App {
-  public static void main(String[] args) throws IOException {
-    String path = args[0];
-    Graph graph = new Graph(path);
-    Stats stats = new Stats(path);
+  public static void main(String[] args) throws IOException, JSAPException {
+    SimpleJSAP jsap = new SimpleJSAP(
+        App.class.getName(),
+        "Server to load and query a compressed graph representation of Software Heritage archive.",
+        new Parameter[] {
+          new FlaggedOption("port", JSAP.INTEGER_PARSER, "5009", JSAP.NOT_REQUIRED, 'p', "port",
+              "Binding port of the server."),
+          new UnflaggedOption("graphPath", JSAP.STRING_PARSER, JSAP.NO_DEFAULT, JSAP.REQUIRED,
+              JSAP.NOT_GREEDY, "The basename of the compressed graph."),
+        }
+    );
+
+    JSAPResult config = jsap.parse(args);
+    if (jsap.messagePrinted()) {
+      System.exit(1);
+    }
+
+    String graphPath = config.getString("graphPath");
+    int port = config.getInt("port");
+
+    startServer(graphPath, port);
+  }
+
+  private static void startServer(String graphPath, int port) throws IOException {
+    Graph graph = new Graph(graphPath);
+    Stats stats = new Stats(graphPath);
 
     // Clean up on exit
     Runtime.getRuntime().addShutdownHook(new Thread() {
@@ -45,7 +74,7 @@
     objectMapper.setPropertyNamingStrategy(PropertyNamingStrategy.SNAKE_CASE);
     JavalinJackson.configure(objectMapper);
 
-    Javalin app = Javalin.create().start(5009);
+    Javalin app = Javalin.create().start(port);
 
     app.before("/stats/*", ctx -> { checkQueryStrings(ctx, ""); });
     app.before("/leaves/*", ctx -> { checkQueryStrings(ctx, "direction|edges"); });
diff --git a/java/server/src/main/java/org/softwareheritage/graph/Endpoint.java b/java/server/src/main/java/org/softwareheritage/graph/Endpoint.java
--- a/java/server/src/main/java/org/softwareheritage/graph/Endpoint.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/Endpoint.java
@@ -14,8 +14,8 @@
  * REST API endpoints wrapper functions.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class Endpoint {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/Graph.java b/java/server/src/main/java/org/softwareheritage/graph/Graph.java
--- a/java/server/src/main/java/org/softwareheritage/graph/Graph.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/Graph.java
@@ -13,8 +13,8 @@
  * Main class storing the compressed graph and node id mappings.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class Graph {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/Neighbors.java b/java/server/src/main/java/org/softwareheritage/graph/Neighbors.java
--- a/java/server/src/main/java/org/softwareheritage/graph/Neighbors.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/Neighbors.java
@@ -11,8 +11,8 @@
  * Iterator class to go over a node neighbors in the graph.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class Neighbors implements Iterable<Long> {
@@ -49,8 +49,8 @@
   * Inner class for {@link Neighbors} iterator.
   *
   * @author Thibault Allançon
-  * @version 1.0
-  * @since 1.0
+  * @version 0.0.1
+  * @since 0.0.1
   */
 
   public class NeighborsIterator implements Iterator<Long> {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/Node.java b/java/server/src/main/java/org/softwareheritage/graph/Node.java
--- a/java/server/src/main/java/org/softwareheritage/graph/Node.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/Node.java
@@ -8,8 +8,8 @@
  * A node in the Software Heritage graph.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class Node {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/SwhId.java b/java/server/src/main/java/org/softwareheritage/graph/SwhId.java
--- a/java/server/src/main/java/org/softwareheritage/graph/SwhId.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/SwhId.java
@@ -10,8 +10,8 @@
  * identifier documentation</a>.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class SwhId {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/SwhPath.java b/java/server/src/main/java/org/softwareheritage/graph/SwhPath.java
--- a/java/server/src/main/java/org/softwareheritage/graph/SwhPath.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/SwhPath.java
@@ -10,8 +10,8 @@
  * Wrapper class to store a list of {@link SwhId}.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  * @see org.softwareheritage.graph.SwhId
  */
 
diff --git a/java/server/src/main/java/org/softwareheritage/graph/algo/Stats.java b/java/server/src/main/java/org/softwareheritage/graph/algo/Stats.java
--- a/java/server/src/main/java/org/softwareheritage/graph/algo/Stats.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/algo/Stats.java
@@ -8,8 +8,8 @@
  * Statistics on the compressed graph.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class Stats {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/algo/Traversal.java b/java/server/src/main/java/org/softwareheritage/graph/algo/Traversal.java
--- a/java/server/src/main/java/org/softwareheritage/graph/algo/Traversal.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/algo/Traversal.java
@@ -18,8 +18,8 @@
  * Traversal algorithms on the compressed graph.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class Traversal {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/backend/MapFile.java b/java/server/src/main/java/org/softwareheritage/graph/backend/MapFile.java
--- a/java/server/src/main/java/org/softwareheritage/graph/backend/MapFile.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/backend/MapFile.java
@@ -11,8 +11,8 @@
  * Wrapper class around very big mmap()-ed file.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class MapFile {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/backend/NodeIdMap.java b/java/server/src/main/java/org/softwareheritage/graph/backend/NodeIdMap.java
--- a/java/server/src/main/java/org/softwareheritage/graph/backend/NodeIdMap.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/backend/NodeIdMap.java
@@ -10,8 +10,8 @@
  * Mapping between internal long node id and external SWH PID.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class NodeIdMap {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/backend/NodeTypesMap.java b/java/server/src/main/java/org/softwareheritage/graph/backend/NodeTypesMap.java
--- a/java/server/src/main/java/org/softwareheritage/graph/backend/NodeTypesMap.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/backend/NodeTypesMap.java
@@ -13,8 +13,8 @@
  * href="https://docs.softwareheritage.org/devel/swh-model/data-model.html">data model</a>.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class NodeTypesMap {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/backend/Setup.java b/java/server/src/main/java/org/softwareheritage/graph/backend/Setup.java
--- a/java/server/src/main/java/org/softwareheritage/graph/backend/Setup.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/backend/Setup.java
@@ -28,8 +28,8 @@
  * Pre-processing steps (such as dumping mapping files on disk) before running the graph service.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class Setup {
diff --git a/java/server/src/main/java/org/softwareheritage/graph/benchmark/LinuxLog.java b/java/server/src/main/java/org/softwareheritage/graph/benchmark/LinuxLog.java
--- a/java/server/src/main/java/org/softwareheritage/graph/benchmark/LinuxLog.java
+++ b/java/server/src/main/java/org/softwareheritage/graph/benchmark/LinuxLog.java
@@ -10,8 +10,8 @@
  * Linux git log experiment to benchmark graph traversal.
  *
  * @author Thibault Allançon
- * @version 1.0
- * @since 1.0
+ * @version 0.0.1
+ * @since 0.0.1
  */
 
 public class LinuxLog {
diff --git a/swh/graph/tests/__init__.py b/swh/graph/tests/__init__.py
--- a/swh/graph/tests/__init__.py
+++ b/swh/graph/tests/__init__.py
@@ -0,0 +1 @@
+SWH_GRAPH_VERSION = '0.0.1'
diff --git a/swh/graph/tests/test_api_client.py b/swh/graph/tests/test_api_client.py
new file mode 100644
--- /dev/null
+++ b/swh/graph/tests/test_api_client.py
@@ -0,0 +1,151 @@
+from pathlib import Path
+import subprocess
+import time
+
+import aiohttp.test_utils
+import pytest
+
+from swh.graph.client import RemoteGraphClient
+from swh.graph.tests import SWH_GRAPH_VERSION
+
+
+@pytest.fixture(scope='module')
+def graph_client():
+    swh_graph_root = Path(__file__).parents[3]
+    java_dir = swh_graph_root / 'java/server'
+
+    # Compile Java server using maven
+    pom_path = java_dir / 'pom.xml'
+    subprocess.run(
+        ['mvn', '-f', str(pom_path), 'compile', 'assembly:single'], check=True)
+
+    port = aiohttp.test_utils.unused_port()
+
+    # Start Java server
+    jar_file = 'swh-graph-{}-jar-with-dependencies.jar'.format(
+        SWH_GRAPH_VERSION)
+    jar_path = java_dir / 'target' / jar_file
+    graph_path = java_dir / 'src/test/dataset/output/example'
+    server = subprocess.Popen([
+        'java', '-cp', str(jar_path),
+        'org.softwareheritage.graph.App', str(graph_path), '-p', str(port)
+    ])
+
+    # Make sure the server is entirely started before running the client
+    time.sleep(1)
+
+    # Start Python client
+    localhost = 'http://0.0.0.0:{}'.format(port)
+    client = RemoteGraphClient(localhost)
+
+    yield client
+
+    print('Service teardown')
+    server.kill()
+
+
+class TestEndpoints:
+    @pytest.fixture(autouse=True)
+    def init_graph_client(self, graph_client):
+        self.client = graph_client
+
+    def test_leaves(self):
+        actual = self.client.leaves(
+            'swh:1:ori:0000000000000000000000000000000000000021'
+        )
+        expected = [
+            'swh:1:cnt:0000000000000000000000000000000000000001',
+            'swh:1:cnt:0000000000000000000000000000000000000004',
+            'swh:1:cnt:0000000000000000000000000000000000000005',
+            'swh:1:cnt:0000000000000000000000000000000000000007'
+        ]
+        assert set(actual) == set(expected)
+
+    def test_neighbors(self):
+        actual = self.client.neighbors(
+            'swh:1:rev:0000000000000000000000000000000000000009',
+            direction='backward'
+        )
+        expected = [
+            'swh:1:snp:0000000000000000000000000000000000000020',
+            'swh:1:rel:0000000000000000000000000000000000000010',
+            'swh:1:rev:0000000000000000000000000000000000000013'
+        ]
+        assert set(actual) == set(expected)
+
+    def test_stats(self):
+        stats = self.client.stats()
+
+        assert set(stats.keys()) == {'counts', 'ratios', 'indegree',
+                                     'outdegree'}
+
+        assert set(stats['counts'].keys()) == {'nodes', 'edges'}
+        assert set(stats['ratios'].keys()) == {'compression', 'bits_per_node',
+                                               'bits_per_edge', 'avg_locality'}
+        assert set(stats['indegree'].keys()) == {'min', 'max', 'avg'}
+        assert set(stats['outdegree'].keys()) == {'min', 'max', 'avg'}
+
+        assert stats['counts']['nodes'] == 21
+        assert stats['counts']['edges'] == 23
+        assert isinstance(stats['ratios']['compression'], float)
+        assert isinstance(stats['ratios']['bits_per_node'], float)
+        assert isinstance(stats['ratios']['bits_per_edge'], float)
+        assert isinstance(stats['ratios']['avg_locality'], float)
+        assert stats['indegree']['min'] == 0
+        assert stats['indegree']['max'] == 3
+        assert isinstance(stats['indegree']['avg'], float)
+        assert stats['outdegree']['min'] == 0
+        assert stats['outdegree']['max'] == 3
+        assert isinstance(stats['outdegree']['avg'], float)
+
+    def test_visit_nodes(self):
+        actual = self.client.visit_nodes(
+            'swh:1:rel:0000000000000000000000000000000000000010',
+            edges='rel:rev,rev:rev'
+        )
+        expected = [
+            'swh:1:rel:0000000000000000000000000000000000000010',
+            'swh:1:rev:0000000000000000000000000000000000000009',
+            'swh:1:rev:0000000000000000000000000000000000000003'
+        ]
+        assert set(actual) == set(expected)
+
+    def test_visit_paths(self):
+        actual = [tuple(path) for path in
+                  self.client.visit_paths(
+                      'swh:1:snp:0000000000000000000000000000000000000020',
+                      edges='snp:*,rev:*')
+                  ]
+        expected = [
+            (
+                'swh:1:snp:0000000000000000000000000000000000000020',
+                'swh:1:rev:0000000000000000000000000000000000000009',
+                'swh:1:rev:0000000000000000000000000000000000000003',
+                'swh:1:dir:0000000000000000000000000000000000000002'
+            ),
+            (
+                'swh:1:snp:0000000000000000000000000000000000000020',
+                'swh:1:rev:0000000000000000000000000000000000000009',
+                'swh:1:dir:0000000000000000000000000000000000000008'
+            ),
+            (
+                'swh:1:snp:0000000000000000000000000000000000000020',
+                'swh:1:rel:0000000000000000000000000000000000000010'
+            )
+        ]
+        assert set(actual) == set(expected)
+
+    def test_walk(self):
+        actual = self.client.walk(
+            'swh:1:dir:0000000000000000000000000000000000000016', 'rel',
+            edges='dir:dir,dir:rev,rev:*',
+            direction='backward',
+            traversal='bfs'
+        )
+        expected = [
+            'swh:1:dir:0000000000000000000000000000000000000016',
+            'swh:1:dir:0000000000000000000000000000000000000017',
+            'swh:1:rev:0000000000000000000000000000000000000018',
+            'swh:1:rel:0000000000000000000000000000000000000019'
+        ]
+        assert set(actual) == set(expected)