diff --git a/packages/next-codemod/transforms/name-default-component.ts b/packages/next-codemod/transforms/name-default-component.ts
index 745de4aaf4f10d7..bcbf7c34202a5b1 100644
--- a/packages/next-codemod/transforms/name-default-component.ts
+++ b/packages/next-codemod/transforms/name-default-component.ts
@@ -1,39 +1,44 @@
 import { basename, extname } from 'path'
 
-const camelCase = (value) => {
+const camelCase = (value: string): string => {
   const val = value.replace(/[-_\s.]+(.)?/g, (_match, chr) =>
     chr ? chr.toUpperCase() : ''
   )
   return val.substr(0, 1).toUpperCase() + val.substr(1)
 }
 
-const isValidIdentifier = (value) => /^[a-zA-ZÀ-ÿ][0-9a-zA-ZÀ-ÿ]+$/.test(value)
+const isValidIdentifier = (value: string): boolean =>
+  /^[a-zA-ZÀ-ÿ][0-9a-zA-ZÀ-ÿ]+$/.test(value)
+
+type Node = {
+  type: string
+  declaration: {
+    type: string
+    body: any
+    id?: any
+  }
+}
 
 export default function transformer(file, api, options) {
   const j = api.jscodeshift
   const root = j(file.source)
 
-  let hasModifications
+  let hasModifications: boolean
 
-  const returnsJSX = (node) =>
+  const returnsJSX = (node): boolean =>
     node.type === 'JSXElement' ||
     (node.type === 'BlockStatement' &&
       j(node)
         .find(j.ReturnStatement)
-        .some(
-          (path) =>
-            path.value.argument && path.value.argument.type === 'JSXElement'
-        ))
+        .some((path) => path.value.argument?.type === 'JSXElement'))
 
-  const hasRootAsParent = (path) => {
+  const hasRootAsParent = (path): boolean => {
     const program = path.parentPath.parentPath.parentPath.parentPath.parentPath
-    return (
-      !program || (program && program.value && program.value.type === 'Program')
-    )
+    return !program || program?.value?.type === 'Program'
   }
 
-  const nameFunctionComponent = (path) => {
-    const node = path.value
+  const nameFunctionComponent = (path): void => {
+    const node: Node = path.value
 
     if (!node.declaration) {
       return