diff --git a/conftest.py b/conftest.py
--- a/conftest.py
+++ b/conftest.py
@@ -3,6 +3,8 @@
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
+import pytest
+
 from hypothesis import settings
 
 # define tests profile. Full documentation is at:
@@ -17,3 +19,10 @@
 
 # we use the swh_scheduler fixture
 pytest_plugins = ["swh.scheduler.pytest_plugin"]
+
+
+@pytest.fixture(scope="session")
+def swh_scheduler_celery_includes(swh_scheduler_celery_includes):
+    return swh_scheduler_celery_includes + [
+        "swh.indexer.tasks",
+    ]
diff --git a/requirements-swh.txt b/requirements-swh.txt
--- a/requirements-swh.txt
+++ b/requirements-swh.txt
@@ -1,6 +1,6 @@
 swh.core[db,http] >= 0.2.2
 swh.model >= 0.0.15
 swh.objstorage >= 0.0.43
-swh.scheduler >= 0.0.47
+swh.scheduler >= 0.5.2
 swh.storage >= 0.12.0
 swh.journal >= 0.1.0
diff --git a/requirements-test.txt b/requirements-test.txt
--- a/requirements-test.txt
+++ b/requirements-test.txt
@@ -1,5 +1,6 @@
 confluent-kafka
 pytest
+pytest-mock
 hypothesis>=3.11.0
 swh.scheduler[testing] >= 0.5.0
 swh.storage[testing] >= 0.10.0
diff --git a/swh/indexer/tasks.py b/swh/indexer/tasks.py
--- a/swh/indexer/tasks.py
+++ b/swh/indexer/tasks.py
@@ -4,7 +4,7 @@
 # See top-level LICENSE file for more information
 
 
-from celery import current_app as app
+from celery import shared_task
 
 from .mimetype import MimetypeIndexer, MimetypePartitionIndexer
 from .ctags import CtagsIndexer
@@ -13,36 +13,36 @@
 from .metadata import OriginMetadataIndexer
 
 
-@app.task(name=__name__ + ".OriginMetadata")
+@shared_task(name=__name__ + ".OriginMetadata")
 def origin_metadata(*args, **kwargs):
     return OriginMetadataIndexer().run(*args, **kwargs)
 
 
-@app.task(name=__name__ + ".Ctags")
+@shared_task(name=__name__ + ".Ctags")
 def ctags(*args, **kwargs):
     return CtagsIndexer().run(*args, **kwargs)
 
 
-@app.task(name=__name__ + ".ContentFossologyLicense")
+@shared_task(name=__name__ + ".ContentFossologyLicense")
 def fossology_license(*args, **kwargs):
     return FossologyLicenseIndexer().run(*args, **kwargs)
 
 
-@app.task(name=__name__ + ".RecomputeChecksums")
+@shared_task(name=__name__ + ".RecomputeChecksums")
 def recompute_checksums(*args, **kwargs):
     return RecomputeChecksums().run(*args, **kwargs)
 
 
-@app.task(name=__name__ + ".ContentMimetype")
+@shared_task(name=__name__ + ".ContentMimetype")
 def mimetype(*args, **kwargs):
     return MimetypeIndexer().run(*args, **kwargs)
 
 
-@app.task(name=__name__ + ".ContentRangeMimetype")
+@shared_task(name=__name__ + ".ContentRangeMimetype")
 def range_mimetype(*args, **kwargs):
     return MimetypePartitionIndexer().run(*args, **kwargs)
 
 
-@app.task(name=__name__ + ".ContentRangeFossologyLicense")
+@shared_task(name=__name__ + ".ContentRangeFossologyLicense")
 def range_license(*args, **kwargs):
     return FossologyLicensePartitionIndexer().run(*args, **kwargs)
diff --git a/swh/indexer/tests/conftest.py b/swh/indexer/tests/conftest.py
--- a/swh/indexer/tests/conftest.py
+++ b/swh/indexer/tests/conftest.py
@@ -3,9 +3,12 @@
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
+import os
+
 from datetime import timedelta
 from unittest.mock import patch
 
+import yaml
 import pytest
 
 from swh.objstorage import get_objstorage
@@ -72,3 +75,27 @@
         "swh.objstorage.factory._STORAGE_CLASSES", {"memory": lambda: objstorage}
     ):
         yield objstorage
+
+
+@pytest.fixture
+def swh_indexer_config():
+    return {
+        "storage": {"cls": "memory"},
+        "objstorage": {"cls": "memory", "args": {},},
+        "indexer_storage": {"cls": "memory", "args": {},},
+        "tools": {
+            "name": "file",
+            "version": "1:5.30-1+deb9u1",
+            "configuration": {"type": "library", "debian-package": "python3-magic"},
+        },
+        "compute_checksums": ["blake2b512"],  # for rehash indexer
+    }
+
+
+@pytest.fixture
+def swh_config(swh_indexer_config, monkeypatch, tmp_path):
+    conffile = os.path.join(str(tmp_path), "loader.yml")
+    with open(conffile, "w") as f:
+        f.write(yaml.dump(swh_indexer_config))
+    monkeypatch.setenv("SWH_CONFIG_FILENAME", conffile)
+    return conffile
diff --git a/swh/indexer/tests/test_tasks.py b/swh/indexer/tests/test_tasks.py
new file mode 100644
--- /dev/null
+++ b/swh/indexer/tests/test_tasks.py
@@ -0,0 +1,123 @@
+# Copyright (C) 2020  The Software Heritage developers
+# See the AUTHORS file at the top-level directory of this distribution
+# License: GNU General Public License version 3, or any later version
+# See top-level LICENSE file for more information
+
+
+def test_task_origin_metadata(
+    mocker, swh_scheduler_celery_app, swh_scheduler_celery_worker, swh_config
+):
+
+    mock_indexer = mocker.patch("swh.indexer.tasks.OriginMetadataIndexer.run")
+    mock_indexer.return_value = {"status": "eventful"}
+
+    res = swh_scheduler_celery_app.send_task(
+        "swh.indexer.tasks.OriginMetadata", args=["origin-url"],
+    )
+    assert res
+    res.wait()
+    assert res.successful()
+
+    assert res.result == {"status": "eventful"}
+
+
+def test_task_ctags(
+    mocker, swh_scheduler_celery_app, swh_scheduler_celery_worker, swh_config
+):
+
+    mock_indexer = mocker.patch("swh.indexer.tasks.CtagsIndexer.run")
+    mock_indexer.return_value = {"status": "eventful"}
+
+    res = swh_scheduler_celery_app.send_task("swh.indexer.tasks.Ctags", args=["id0"],)
+    assert res
+    res.wait()
+    assert res.successful()
+
+    assert res.result == {"status": "eventful"}
+
+
+def test_task_fossology_license(
+    mocker, swh_scheduler_celery_app, swh_scheduler_celery_worker, swh_config
+):
+
+    mock_indexer = mocker.patch("swh.indexer.tasks.FossologyLicenseIndexer.run")
+    mock_indexer.return_value = {"status": "eventful"}
+
+    res = swh_scheduler_celery_app.send_task(
+        "swh.indexer.tasks.ContentFossologyLicense", args=["id0"],
+    )
+    assert res
+    res.wait()
+    assert res.successful()
+
+    assert res.result == {"status": "eventful"}
+
+
+def test_task_recompute_checksums(
+    mocker, swh_scheduler_celery_app, swh_scheduler_celery_worker, swh_config
+):
+
+    mock_indexer = mocker.patch("swh.indexer.tasks.RecomputeChecksums.run")
+    mock_indexer.return_value = {"status": "eventful"}
+
+    res = swh_scheduler_celery_app.send_task(
+        "swh.indexer.tasks.RecomputeChecksums", args=[[{"blake2b256": "id"}]],
+    )
+    assert res
+    res.wait()
+    assert res.successful()
+
+    assert res.result == {"status": "eventful"}
+
+
+def test_task_mimetype(
+    mocker, swh_scheduler_celery_app, swh_scheduler_celery_worker, swh_config
+):
+
+    mock_indexer = mocker.patch("swh.indexer.tasks.MimetypeIndexer.run")
+    mock_indexer.return_value = {"status": "eventful"}
+
+    res = swh_scheduler_celery_app.send_task(
+        "swh.indexer.tasks.ContentMimetype", args=["id0"],
+    )
+    assert res
+    res.wait()
+    assert res.successful()
+
+    assert res.result == {"status": "eventful"}
+
+
+def test_task_range_mimetype(
+    mocker, swh_scheduler_celery_app, swh_scheduler_celery_worker, swh_config
+):
+
+    mock_indexer = mocker.patch("swh.indexer.tasks.MimetypePartitionIndexer.run")
+    mock_indexer.return_value = {"status": "eventful"}
+
+    res = swh_scheduler_celery_app.send_task(
+        "swh.indexer.tasks.ContentRangeMimetype", args=[0, 4],
+    )
+    assert res
+    res.wait()
+    assert res.successful()
+
+    assert res.result == {"status": "eventful"}
+
+
+def test_task_range_license(
+    mocker, swh_scheduler_celery_app, swh_scheduler_celery_worker, swh_config
+):
+
+    mock_indexer = mocker.patch(
+        "swh.indexer.tasks.FossologyLicensePartitionIndexer.run"
+    )
+    mock_indexer.return_value = {"status": "eventful"}
+
+    res = swh_scheduler_celery_app.send_task(
+        "swh.indexer.tasks.ContentRangeFossologyLicense", args=[0, 4],
+    )
+    assert res
+    res.wait()
+    assert res.successful()
+
+    assert res.result == {"status": "eventful"}