diff --git a/peppy/const.py b/peppy/const.py
index 0f009a52..1408cdc1 100644
--- a/peppy/const.py
+++ b/peppy/const.py
@@ -17,7 +17,7 @@
 SAMPLE_MODS_KEY = "sample_modifiers"
 PROJ_MODS_KEY = "project_modifiers"
 NAME_TABLE_ATTR = "sample_table"
-CONSTANT_KEY = "append"
+APPEND_KEY = "append"
 REMOVE_KEY = "remove"
 DUPLICATED_KEY = "duplicate"
 DERIVED_KEY = "derive"
@@ -33,11 +33,11 @@
 AMENDMENTS_KEY = "amend"
 ACTIVE_AMENDMENTS_KEY = "_" + AMENDMENTS_KEY
 SAMPLE_EDIT_FLAG_KEY = "_samples_touched"
-SAMPLE_MODIFIERS = [CONSTANT_KEY, IMPLIED_KEY, DERIVED_KEY, DUPLICATED_KEY, REMOVE_KEY]
+SAMPLE_MODIFIERS = [APPEND_KEY, IMPLIED_KEY, DERIVED_KEY, DUPLICATED_KEY, REMOVE_KEY]
 PROJECT_MODIFIERS = [CFG_IMPORTS_KEY, AMENDMENTS_KEY]
 PROJECT_CONSTANTS = [
     "REQUIRED_VERSION",
-    "CONSTANT_KEY",
+    "APPEND_KEY",
     "DERIVED_SOURCES_KEY",
     "DERIVED_KEY",
     "SAMPLE_MODS_KEY",
diff --git a/peppy/project.py b/peppy/project.py
index 48dc9e9f..d2701111 100644
--- a/peppy/project.py
+++ b/peppy/project.py
@@ -27,7 +27,7 @@
     CONFIG_FILE_KEY,
     CONFIG_KEY,
     CONFIG_VERSION_KEY,
-    CONSTANT_KEY,
+    APPEND_KEY,
     DERIVED_ATTRS_KEY,
     DERIVED_KEY,
     DERIVED_SOURCES_KEY,
@@ -587,8 +587,8 @@ def attr_constants(self):
         Update each Sample with constants declared by a Project.
         If Project does not declare constants, no update occurs.
         """
-        if self._modifier_exists(CONSTANT_KEY):
-            to_append = self[CONFIG_KEY][SAMPLE_MODS_KEY][CONSTANT_KEY]
+        if self._modifier_exists(APPEND_KEY):
+            to_append = self[CONFIG_KEY][SAMPLE_MODS_KEY][APPEND_KEY]
             _LOGGER.debug("Applying constant attributes: {}".format(to_append))
 
             for s in track(