diff --git a/src/lib/merge-configs.ts b/src/lib/merge-configs.ts
index eb7a2573..c3d41dd2 100644
--- a/src/lib/merge-configs.ts
+++ b/src/lib/merge-configs.ts
@@ -6,16 +6,16 @@ import { Config, ConfigExtension } from './types'
  */
 export function mergeConfigs(
     baseConfig: Config,
-    { cacheSize, prefix, separator, extend = {}, ...configOverride }: ConfigExtension,
+    { cacheSize, prefix, separator, extend = {}, override = {} }: ConfigExtension,
 ) {
     overrideProperty(baseConfig, 'cacheSize', cacheSize)
     overrideProperty(baseConfig, 'prefix', prefix)
     overrideProperty(baseConfig, 'separator', separator)
 
-    for (const configKey in configOverride) {
+    for (const configKey in override) {
         overrideConfigProperties(
-            baseConfig[configKey as keyof typeof configOverride],
-            configOverride[configKey as keyof typeof configOverride],
+            baseConfig[configKey as keyof typeof override],
+            override[configKey as keyof typeof override],
         )
     }
 
diff --git a/src/lib/types.ts b/src/lib/types.ts
index d3525733..3bee64a0 100644
--- a/src/lib/types.ts
+++ b/src/lib/types.ts
@@ -1,4 +1,6 @@
-export interface Config {
+export interface Config extends ConfigStatic, ConfigGroups {}
+
+interface ConfigStatic {
     /**
      * Integer indicating size of LRU cache used for memoizing results.
      * - Cache might be up to twice as big as `cacheSize`
@@ -19,6 +21,13 @@ export interface Config {
      * Theme scales used in classGroups.
      * The keys are the same as in the Tailwind config but the values are sometimes defined more broadly.
      */
+}
+
+interface ConfigGroups {
+    /**
+     * Theme scales used in classGroups.
+     * The keys are the same as in the Tailwind config but the values are sometimes defined more broadly.
+     */
     theme: ThemeObject
     /**
      * Object with groups of classes.
@@ -46,15 +55,9 @@ export interface Config {
     conflictingClassGroupModifiers: Record<ClassGroupId, readonly ClassGroupId[]>
 }
 
-export type ConfigExtend = Partial<
-    Pick<
-        Config,
-        'theme' | 'classGroups' | 'conflictingClassGroups' | 'conflictingClassGroupModifiers'
-    >
->
-
-export interface ConfigExtension extends Partial<Config> {
-    extend?: ConfigExtend
+export interface ConfigExtension extends Partial<ConfigStatic> {
+    override?: Partial<ConfigGroups>
+    extend?: Partial<ConfigGroups>
 }
 
 export type ThemeObject = Record<string, ClassGroup>