diff --git a/securedrop/tests/test_i18n.py b/securedrop/tests/test_i18n.py
index 8f0a633d79..6b12f966f5 100644
--- a/securedrop/tests/test_i18n.py
+++ b/securedrop/tests/test_i18n.py
@@ -30,6 +30,7 @@
 import journalist_app as journalist_app_module
 import pytest
 import source_app
+from utils.env import TESTS_DIR
 
 from sh import sed, pybabel
 
@@ -174,14 +175,14 @@ def test_i18n(journalist_app, config):
     del journalist_app
 
     sources = [
-        'tests/i18n/code.py',
-        'tests/i18n/template.html',
+        os.path.join(TESTS_DIR, 'i18n/code.py'),
+        os.path.join(TESTS_DIR, 'i18n/template.html'),
     ]
 
     i18n_tool.I18NTool().main([
         '--verbose',
         'translate-messages',
-        '--mapping', 'tests/i18n/babel.cfg',
+        '--mapping', os.path.join(TESTS_DIR, 'i18n/babel.cfg'),
         '--translations-dir', config.TEMP_DIR,
         '--sources', ",".join(sources),
         '--extract-update',
diff --git a/securedrop/tests/test_template_filters.py b/securedrop/tests/test_template_filters.py
index 69e7d07ba9..c2ef48204d 100644
--- a/securedrop/tests/test_template_filters.py
+++ b/securedrop/tests/test_template_filters.py
@@ -10,6 +10,7 @@
 import journalist_app
 import source_app
 import template_filters
+from utils.env import TESTS_DIR
 
 from sh import pybabel
 
@@ -98,9 +99,9 @@ def do_test(config, create_app):
     i18n_tool.I18NTool().main([
         '--verbose',
         'translate-messages',
-        '--mapping', 'tests/i18n/babel.cfg',
+        '--mapping', os.path.join(TESTS_DIR, 'i18n/babel.cfg'),
         '--translations-dir', config.TEMP_DIR,
-        '--sources', 'tests/i18n/code.py',
+        '--sources', os.path.join(TESTS_DIR, 'i18n/code.py'),
         '--extract-update',
         '--compile',
     ])
diff --git a/securedrop/tests/utils/env.py b/securedrop/tests/utils/env.py
index bb90a5a078..0f64bf44ff 100644
--- a/securedrop/tests/utils/env.py
+++ b/securedrop/tests/utils/env.py
@@ -14,7 +14,8 @@
 
 from db import db
 
-FILES_DIR = abspath(join(dirname(realpath(__file__)), '..', 'files'))
+TESTS_DIR = abspath(join(dirname(realpath(__file__)), '..'))
+FILES_DIR = join(TESTS_DIR, 'files')
 
 # The PID file for the redis worker is hard-coded below.  Ideally this
 # constant would be provided by a test harness.  It has been intentionally