diff --git a/packages/cluster/src/common.js b/packages/cluster/src/common.js
index a2125ef0..a1b289a0 100644
--- a/packages/cluster/src/common.js
+++ b/packages/cluster/src/common.js
@@ -155,7 +155,9 @@ module.exports.makeEnvironment = cfg => {
         DHIS2_CORE_VERSION: cfg.dhis2Version,
         DHIS2_CORE_DB_VERSION: cfg.dbVersion,
         DHIS2_CORE_PORT: cfg.port,
-        DHIS2_CORE_CONFIG: cfg.dhis2Config,
+    }
+    if (cfg.dhis2Config) {
+        env.DHIS2_CORE_CONFIG = cfg.dhis2Config
     }
 
     reporter.debug('Runtime environment\n', env)
diff --git a/packages/cluster/tests/setup-environment.js b/packages/cluster/tests/setup-environment.js
index 42b3107e..5da1fd7c 100644
--- a/packages/cluster/tests/setup-environment.js
+++ b/packages/cluster/tests/setup-environment.js
@@ -27,7 +27,6 @@ test('build runtime environment based on defaults', async function(t) {
         DHIS2_CORE_VERSION: 'dev',
         DHIS2_CORE_DB_VERSION: 'dev',
         DHIS2_CORE_PORT: defaults.port,
-        DHIS2_CORE_CONFIG: undefined,
     }
 
     t.deepEqual(actual, expected, 'default environment')
@@ -57,7 +56,6 @@ test('build runtime environment based on args', async function(t) {
         DHIS2_CORE_VERSION: '2.33',
         DHIS2_CORE_DB_VERSION: '2.32',
         DHIS2_CORE_PORT: 8233,
-        DHIS2_CORE_CONFIG: undefined,
     }
 
     t.deepEqual(actual, expected, 'args environment')
@@ -90,7 +88,6 @@ test('build runtime environment based on mixed args and config', async function(
         DHIS2_CORE_VERSION: 'master',
         DHIS2_CORE_DB_VERSION: 'dev',
         DHIS2_CORE_PORT: 8233,
-        DHIS2_CORE_CONFIG: undefined,
     }
 
     t.deepEqual(actual, expected, 'args and config environment')
@@ -124,7 +121,6 @@ test('build runtime environment based on mixed args, cache, config and defaults'
         DHIS2_CORE_VERSION: 'dev',
         DHIS2_CORE_DB_VERSION: 'dev',
         DHIS2_CORE_PORT: 8233,
-        DHIS2_CORE_CONFIG: undefined,
     }
 
     t.deepEqual(actual, expected, 'merged environment')
@@ -165,7 +161,6 @@ test('build runtime environment based on mixed args, cache, config, custom per-c
         DHIS2_CORE_VERSION: 'apa',
         DHIS2_CORE_DB_VERSION: 'dev',
         DHIS2_CORE_PORT: 9999,
-        DHIS2_CORE_CONFIG: undefined,
     }
 
     t.deepEqual(actual, expected, 'merged environment')