diff --git a/README.md b/README.md
index 9feb9f72..44162b1c 100644
--- a/README.md
+++ b/README.md
@@ -24,7 +24,7 @@ npm i breadc
 Try [./examples/echo.ts](./examples/echo.ts).
 
 ```ts
-import breadc from 'breadc'
+import { breadc } from 'breadc'
 
 const cli = breadc('echo', { version: '1.0.0' })
   .option('--host <host>', { default: 'localhost' })
diff --git a/examples/echo.ts b/examples/echo.ts
index e73c876e..009885d5 100644
--- a/examples/echo.ts
+++ b/examples/echo.ts
@@ -1,4 +1,4 @@
-import breadc from '../packages/breadc/src';
+import { breadc } from '../packages/breadc/src';
 
 const cli = breadc('echo', { version: '1.0.0' })
   .option('--host <host>', { default: 'localhost' })
diff --git a/examples/genType.ts b/examples/genType.ts
index 03e7fa74..b526a134 100644
--- a/examples/genType.ts
+++ b/examples/genType.ts
@@ -1,4 +1,4 @@
-import breadc from '../packages/breadc/src';
+import { breadc } from '../packages/breadc/src';
 
 const cli = breadc('genType');
 
diff --git a/examples/vite.ts b/examples/vite.ts
index 83dabf07..4cd85d05 100644
--- a/examples/vite.ts
+++ b/examples/vite.ts
@@ -1,4 +1,4 @@
-import breadc from '../packages/breadc/src';
+import { breadc } from '../packages/breadc/src';
 
 const vite = breadc('vite', {
   version: '1.0.0',
diff --git a/packages/breadc/README.md b/packages/breadc/README.md
index 9feb9f72..44162b1c 100644
--- a/packages/breadc/README.md
+++ b/packages/breadc/README.md
@@ -24,7 +24,7 @@ npm i breadc
 Try [./examples/echo.ts](./examples/echo.ts).
 
 ```ts
-import breadc from 'breadc'
+import { breadc } from 'breadc'
 
 const cli = breadc('echo', { version: '1.0.0' })
   .option('--host <host>', { default: 'localhost' })
diff --git a/packages/breadc/src/index.ts b/packages/breadc/src/index.ts
index 5b2ca0cb..3a2b5b68 100644
--- a/packages/breadc/src/index.ts
+++ b/packages/breadc/src/index.ts
@@ -1,5 +1,3 @@
-import { breadc } from './breadc';
-
 export type {
   AppOption,
   Breadc,
@@ -16,5 +14,3 @@ export { definePlugin } from './plugin';
 export { makeTreeNode } from './parser';
 
 export { ParseError, BreadcError } from './error';
-
-export default breadc;
diff --git a/packages/breadc/src/logger.ts b/packages/breadc/src/logger.ts
deleted file mode 100644
index 9bbe3cc6..00000000
--- a/packages/breadc/src/logger.ts
+++ /dev/null
@@ -1,57 +0,0 @@
-import { blue, gray, red, yellow } from '@breadc/color';
-
-export type LoggerFn = (message: string, ...args: any[]) => void;
-
-export interface Logger {
-  println: LoggerFn;
-  info: LoggerFn;
-  warn: LoggerFn;
-  error: LoggerFn;
-  debug: LoggerFn;
-}
-
-export function createDefaultLogger(
-  name: string,
-  logger?: Partial<Logger> | LoggerFn
-): Logger {
-  const println: LoggerFn =
-    !!logger && typeof logger === 'function'
-      ? logger
-      : logger?.println ??
-        ((message: string, ...args: any[]) => {
-          console.log(message, ...args);
-        });
-
-  const info =
-    typeof logger === 'object' && logger?.info
-      ? logger.info
-      : (message: string, ...args: any[]) => {
-          println(`${blue('INFO')} ${message}`, ...args);
-        };
-  const warn =
-    typeof logger === 'object' && logger?.warn
-      ? logger.warn
-      : (message: string, ...args: any[]) => {
-          println(`${yellow('WARN')} ${message}`, ...args);
-        };
-  const error =
-    typeof logger === 'object' && logger?.error
-      ? logger.error
-      : (message: string, ...args: any[]) => {
-          println(`${red('ERROR')} ${message}`, ...args);
-        };
-  const debug =
-    typeof logger === 'object' && logger?.debug
-      ? logger.debug
-      : (message: string, ...args: any[]) => {
-          println(`${gray(name)} ${message}`, ...args);
-        };
-
-  return {
-    println,
-    info,
-    warn,
-    error,
-    debug
-  };
-}