diff --git a/src/main/java/com/keepgoing/keepserver/domain/book/payload/request/BookDto.java b/src/main/java/com/keepgoing/keepserver/domain/book/payload/request/BookDto.java
index cf3096e..2eefc03 100644
--- a/src/main/java/com/keepgoing/keepserver/domain/book/payload/request/BookDto.java
+++ b/src/main/java/com/keepgoing/keepserver/domain/book/payload/request/BookDto.java
@@ -1,20 +1,21 @@
 package com.keepgoing.keepserver.domain.book.payload.request;
 
 import com.keepgoing.keepserver.domain.book.entity.enums.BookState;
+import lombok.Builder;
 import lombok.Getter;
 import lombok.Setter;
 
 import java.time.LocalDateTime;
 
-@Getter
-@Setter
-public class BookDto {
-    private long id;
-    private String bookName;
-    private String writer;
-    private String imageUrl;
-    private String nfcCode;
-    private LocalDateTime registrationDate;
-    private LocalDateTime rentDate;
-    private BookState state;
+@Builder
+public record BookDto (
+        Long id,
+        String bookName,
+        String writer,
+        String imageUrl,
+        String nfcCode,
+        LocalDateTime registrationDate,
+        LocalDateTime rentDate,
+        BookState state
+) {
 }
diff --git a/src/main/java/com/keepgoing/keepserver/domain/book/payload/request/BookRequestDto.java b/src/main/java/com/keepgoing/keepserver/domain/book/payload/request/BookRequestDto.java
index 58401db..dcbbaba 100644
--- a/src/main/java/com/keepgoing/keepserver/domain/book/payload/request/BookRequestDto.java
+++ b/src/main/java/com/keepgoing/keepserver/domain/book/payload/request/BookRequestDto.java
@@ -1,12 +1,14 @@
 package com.keepgoing.keepserver.domain.book.payload.request;
 
 import com.keepgoing.keepserver.domain.book.entity.enums.BookState;
+import lombok.Builder;
 import lombok.Getter;
 
-@Getter
-public class BookRequestDto {
-    private String name;
-    private String nfcCode;
-    private String imageUrl;
-    private BookState state;
+@Builder
+public record BookRequestDto (
+        String name,
+        String nfcCode,
+        String imageUrl,
+        BookState state
+){
 }
diff --git a/src/main/java/com/keepgoing/keepserver/domain/book/repository/BookRepository.java b/src/main/java/com/keepgoing/keepserver/domain/book/repository/BookRepository.java
index 08e026a..aebd163 100644
--- a/src/main/java/com/keepgoing/keepserver/domain/book/repository/BookRepository.java
+++ b/src/main/java/com/keepgoing/keepserver/domain/book/repository/BookRepository.java
@@ -12,6 +12,5 @@
 public interface BookRepository extends JpaRepository<Book, Long> {
     Book findBookByNfcCode(String NfcCode);
     Optional<Book> findBookByNfcCodeContaining(String NfcCode);
-    Optional<Book> findByBookName(String bookName);
     List<Book> findByBorrower(User borrower);
 }
diff --git a/src/main/java/com/keepgoing/keepserver/domain/device/service/DeviceServiceImpl.java b/src/main/java/com/keepgoing/keepserver/domain/device/service/DeviceServiceImpl.java
index f5ab3aa..91a003f 100644
--- a/src/main/java/com/keepgoing/keepserver/domain/device/service/DeviceServiceImpl.java
+++ b/src/main/java/com/keepgoing/keepserver/domain/device/service/DeviceServiceImpl.java
@@ -72,7 +72,8 @@ public BaseResponse editDevice(Long id, DeviceEditRequest deviceEditRequest) {
     }
 
     public User findUserByEmail(String email) {
-        return userRepository.findByEmail(email).orElseThrow(() -> new DeviceException(DeviceError.USER_NOT_FOUND));
+        return userRepository.findByEmail(email)
+                .orElseThrow(DeviceException::userNotFound);
     }
 
     private Device findDeviceById(Long id) {
diff --git a/src/main/java/com/keepgoing/keepserver/domain/rent/presentation/RentController.java b/src/main/java/com/keepgoing/keepserver/domain/rent/presentation/RentController.java
index 3644e94..492b5de 100644
--- a/src/main/java/com/keepgoing/keepserver/domain/rent/presentation/RentController.java
+++ b/src/main/java/com/keepgoing/keepserver/domain/rent/presentation/RentController.java
@@ -13,7 +13,9 @@
 @RequestMapping("/rent")
 @RequiredArgsConstructor
 public class RentController {
+
     private final RentService rentService;
+
     @Operation(summary = "기자재 대여", description = "기자재를 대여합니다.")
     @PostMapping("/device")
     public BaseResponse rentDevice(@RequestParam String deviceName, @RequestParam String email) {
diff --git a/src/main/java/com/keepgoing/keepserver/domain/returns/presentation/ReturnController.java b/src/main/java/com/keepgoing/keepserver/domain/returns/presentation/ReturnController.java
index 6f654ce..b07bc18 100644
--- a/src/main/java/com/keepgoing/keepserver/domain/returns/presentation/ReturnController.java
+++ b/src/main/java/com/keepgoing/keepserver/domain/returns/presentation/ReturnController.java
@@ -13,6 +13,7 @@
 @RequestMapping("/return")
 @RequiredArgsConstructor
 public class ReturnController {
+
     private final ReturnService returnService;
 
     @Operation(summary = "기자재 반납", description = "기자재 이름과 이메일을 통해 기자재를 반납합니다.")
diff --git a/src/main/java/com/keepgoing/keepserver/domain/student/service/StudentServiceImpl.java b/src/main/java/com/keepgoing/keepserver/domain/student/service/StudentServiceImpl.java
index 4d1dd1c..e0d082a 100644
--- a/src/main/java/com/keepgoing/keepserver/domain/student/service/StudentServiceImpl.java
+++ b/src/main/java/com/keepgoing/keepserver/domain/student/service/StudentServiceImpl.java
@@ -132,7 +132,7 @@ public BaseResponse findByStudentNum(StudentFindDto studentDto) {
         }
     }
 
-    public BaseResponse editStudent(StudentRequestDto studentDto,Long id) {
+    public BaseResponse editStudent(StudentRequestDto studentDto, Long id) {
         Student studentEntity = studentRepository.findStudentById(id);
         if (studentDto.getStudentName() != null) studentEntity.setStudentName(studentDto.getStudentName());
         if (studentDto.getPhoneNum() != null) studentEntity.setPhoneNum(studentDto.getPhoneNum());
diff --git a/src/main/java/com/keepgoing/keepserver/global/config/SpringConfig.java b/src/main/java/com/keepgoing/keepserver/global/config/SpringConfig.java
deleted file mode 100644
index b10a8a6..0000000
--- a/src/main/java/com/keepgoing/keepserver/global/config/SpringConfig.java
+++ /dev/null
@@ -1,15 +0,0 @@
-package com.keepgoing.keepserver.global.config;
-
-import org.springframework.context.annotation.Bean;
-import org.springframework.context.annotation.Configuration;
-import org.springframework.web.client.RestTemplate;
-
-@Configuration
-public class SpringConfig {
-
-    @Bean
-    public RestTemplate restTemplate() {
-        return new RestTemplate();
-    }
-
-}
diff --git a/src/main/java/com/keepgoing/keepserver/global/exception/book/BookException.java b/src/main/java/com/keepgoing/keepserver/global/exception/book/BookException.java
index 7e35167..6011b8f 100644
--- a/src/main/java/com/keepgoing/keepserver/global/exception/book/BookException.java
+++ b/src/main/java/com/keepgoing/keepserver/global/exception/book/BookException.java
@@ -27,7 +27,7 @@ public static BookException bookNotAvailable() {
     public static BookException imageUploadFailed() {
         return IMAGE_UPLOAD_FAILED;
     }
-    public static BookException invalidborrower() {
+    public static BookException invalidBorrower() {
         return INVALID_BORROWER;
     }
 }