diff --git a/docker-compose-dev.yml b/docker-compose-dev.yml
index 5c674d96..d9d430af 100644
--- a/docker-compose-dev.yml
+++ b/docker-compose-dev.yml
@@ -49,6 +49,7 @@ services:
 
   dcd-mapping:
     build: ../dcd_mapping
+    platform: linux/amd64
     image: dcd-mapping:dev
     command: bash -c "uvicorn api.server_main:app --host 0.0.0.0 --port 8000 --reload"
     depends_on:
@@ -59,6 +60,7 @@ services:
     ports:
       - "8004:8000"
     volumes:
+      - ../dcd_mapping:/usr/src/app
       - mavedb-seqrepo-dev:/usr/local/share/seqrepo
 
   cdot-rest:
diff --git a/tests/conftest.py b/tests/conftest.py
index c79c033e..b11f728c 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1,7 +1,7 @@
 import logging  # noqa: F401
+import sys
 from datetime import datetime
 from unittest import mock
-import sys
 
 import email_validator
 import pytest
@@ -11,35 +11,33 @@
 from sqlalchemy.pool import NullPool
 
 from mavedb.db.base import Base
+from mavedb.models import *  # noqa: F403
+from mavedb.models.experiment import Experiment
 from mavedb.models.experiment_set import ExperimentSet
-from mavedb.models.score_set_publication_identifier import ScoreSetPublicationIdentifierAssociation
-from mavedb.models.user import User, UserRole, Role
 from mavedb.models.license import License
-from mavedb.models.taxonomy import Taxonomy
-from mavedb.models.publication_identifier import PublicationIdentifier
-from mavedb.models.experiment import Experiment
-from mavedb.models.variant import Variant
 from mavedb.models.mapped_variant import MappedVariant
+from mavedb.models.publication_identifier import PublicationIdentifier
 from mavedb.models.score_set import ScoreSet
-
-from mavedb.models import *  # noqa: F403
-
+from mavedb.models.score_set_publication_identifier import ScoreSetPublicationIdentifierAssociation
+from mavedb.models.taxonomy import Taxonomy
+from mavedb.models.user import Role, User, UserRole
+from mavedb.models.variant import Variant
 from tests.helpers.constants import (
     ADMIN_USER,
     EXTRA_USER,
-    TEST_LICENSE,
+    TEST_BRNICH_SCORE_CALIBRATION,
     TEST_INACTIVE_LICENSE,
+    TEST_LICENSE,
+    TEST_PATHOGENICITY_SCORE_CALIBRATION,
+    TEST_PUBMED_IDENTIFIER,
     TEST_SAVED_TAXONOMY,
     TEST_USER,
-    VALID_VARIANT_URN,
-    VALID_SCORE_SET_URN,
-    VALID_EXPERIMENT_URN,
-    VALID_EXPERIMENT_SET_URN,
-    TEST_PUBMED_IDENTIFIER,
     TEST_VALID_POST_MAPPED_VRS_ALLELE_VRS2_X,
     TEST_VALID_PRE_MAPPED_VRS_ALLELE_VRS2_X,
-    TEST_BRNICH_SCORE_CALIBRATION,
-    TEST_PATHOGENICITY_SCORE_CALIBRATION,
+    VALID_EXPERIMENT_SET_URN,
+    VALID_EXPERIMENT_URN,
+    VALID_SCORE_SET_URN,
+    VALID_VARIANT_URN,
 )
 
 sys.path.append(".")
@@ -56,7 +54,7 @@
 assert pytest_postgresql.factories
 
 # Allow the @test domain name through our email validator.
-email_validator.SPECIAL_USE_DOMAIN_NAMES.remove("test")
+email_validator.TEST_ENVIRONMENT = True
 
 
 @pytest.fixture()