diff --git a/mod.ts b/mod.ts
index 0ceeb18..80ea6a1 100644
--- a/mod.ts
+++ b/mod.ts
@@ -1,2 +1,2 @@
-export { isDarkMode } from './src/accessibility.js'
-export { xbar, separator } from './src/index.js'
\ No newline at end of file
+export { isDarkMode } from './src/accessibility.ts'
+export { xbar, separator } from './src/index.ts'
\ No newline at end of file
diff --git a/src/accessibility.js b/src/accessibility.js
deleted file mode 100644
index 69d4b12..0000000
--- a/src/accessibility.js
+++ /dev/null
@@ -1,78 +0,0 @@
-import {
-  pipe,
-  pipeCompatibleFilter,
-  pipeCompatibleMap,
-  pipeCompatibleReduce,
-  pipeCompatibleSplit,
-} from './utility.js';
-// array access layer
-const lastIndex = (arr) => arr.length - 1;
-const lastItem = (arr) => arr[lastIndex(arr)];
-
-// array element transform layer
-const appendLastLine = (lines, word) => [
-  ...lines.slice(0, lastIndex(lines)),
-  lastItem(lines).concat(' ', word),
-];
-const newLine = (lines, newLine) => lines.concat(newLine);
-
-// conditional logic layer
-const isUnderLimit = (line, word, lineLength) =>
-  line.length + word.length + 1 <= lineLength || line === ''; //if line is empty always return true
-
-// array reducer
-const reduceLines = (lineLength) =>
-  (lines, word) => {
-    return isUnderLimit(lastItem(lines), word, lineLength)
-      ? appendLastLine(lines, word)
-      : newLine(lines, word);
-  };
-
-// word wrap transformations
-const spiltToWords = pipeCompatibleSplit(' ');
-const removeExtraSpaces = pipeCompatibleFilter((word) => word !== '');
-
-const reduceToLines = (maxLineLength) =>
-  pipeCompatibleReduce(reduceLines(maxLineLength))(['']);
-
-const passPropertiesToLInes = (propertiesToPass) =>
-  pipeCompatibleMap((line) => ({
-    text: line.trim(),
-    ...propertiesToPass,
-  }));
-
-// apply transformations in order with pipe
-const applyWordWrap = ({ text, wordWrap, ...menuItemProperties }) =>
-  pipe(
-    spiltToWords,
-    removeExtraSpaces,
-    reduceToLines(wordWrap),
-    passPropertiesToLInes(menuItemProperties),
-  )(text);
-
-// entry layer conditional logic
-const hasWordWrap = (item) => !!item.wordWrap;
-const hasText = (item) => !!item.text;
-const shouldApplyWordWrap = (item) => hasWordWrap(item) && hasText(item);
-
-// deno-lint-ignore no-unused-vars
-const ignoreWordWrap = ({ wordWrap, ...item }) => item;
-
-// entry layer
-export const wordWrap = (menuItem) =>
-  shouldApplyWordWrap(menuItem)
-    ? applyWordWrap(menuItem)
-    : [ignoreWordWrap(menuItem)];
-
-/**
- * returns true if XBARDarkMode is enabled.
- * allways returns false if 'env' permission has not been previously granted.
- * @async
- * @returns {Promise<boolean>}
- */
-export const isDarkMode = async () => {
-  const permissions = await Deno.permissions.query({ name: 'env' });
-  return permissions.state === 'granted'
-    ? Deno.env.get('XBARDarkMode') === 'true'
-    : false;
-};
diff --git a/src/accessibility.ts b/src/accessibility.ts
new file mode 100644
index 0000000..862cfd7
--- /dev/null
+++ b/src/accessibility.ts
@@ -0,0 +1,89 @@
+import {
+  pipe,
+  pipeCompatibleFilter,
+  pipeCompatibleMap,
+  pipeCompatibleReduce,
+  pipeCompatibleSplit,
+} from './utility.ts';
+
+import { Menu, MenuItem } from './types.d.ts';
+// array access layer
+const lastIndex = (arr: string[]) => arr.length - 1;
+const lastItem = (arr: string[]) => arr[lastIndex(arr)];
+
+// array element transform layer
+const appendLastLine = (lines: string[], word: string) => [
+  ...lines.slice(0, lastIndex(lines)),
+  lastItem(lines).concat(' ', word),
+];
+const newLine = (lines: string[], newLine: string) => lines.concat(newLine);
+
+// conditional logic layer
+const isUnderLimit = (line: string, word: string, lineLength: number) =>
+  line.length + word.length + 1 <= lineLength || line === ''; //if line is empty always return true
+
+// array reducer
+const reduceLines = (lineLength: number) =>
+  (lines: string[], word: string) => {
+    return isUnderLimit(lastItem(lines), word, lineLength)
+      ? appendLastLine(lines, word)
+      : newLine(lines, word);
+  };
+
+// word wrap transformations
+const spiltToWords = pipeCompatibleSplit(' ');
+const removeExtraSpaces = pipeCompatibleFilter((word: string) => word !== '');
+
+const reduceToLines = (maxLineLength: number) =>
+  pipeCompatibleReduce(reduceLines(maxLineLength))(['']);
+
+const passPropertiesToLInes = (propertiesToPass: Menu) =>
+  pipeCompatibleMap((line: string) => ({
+    text: line.trim(),
+    ...propertiesToPass,
+  }));
+
+const castToType = (menuItem: MenuItem): { text: string; wordWrap: number } => (
+  {
+    text: `${menuItem.text}`,
+    wordWrap: parseInt(`${menuItem.wordWrap}`),
+    ...menuItem,
+  }
+);
+
+// apply transformations in order with pipe
+const applyWordWrap = (
+  { text, wordWrap, ...menuItemProperties }: { text: string; wordWrap: number },
+): MenuItem[] =>
+  pipe(
+    spiltToWords,
+    removeExtraSpaces,
+    reduceToLines(wordWrap),
+    passPropertiesToLInes(menuItemProperties),
+  )(text);
+
+// entry layer conditional logic
+const hasWordWrap = (item: MenuItem) => !!item.wordWrap;
+const hasText = (item: MenuItem) => !!item.text;
+const shouldApplyWordWrap = (item: MenuItem) =>
+  hasWordWrap(item) && hasText(item);
+
+// deno-lint-ignore no-unused-vars
+const ignoreWordWrap = ({ wordWrap, ...item }: MenuItem) => item;
+
+// entry layer
+export const wordWrap = (menuItem: MenuItem) =>
+  shouldApplyWordWrap(menuItem)
+    ? applyWordWrap(castToType(menuItem))
+    : [ignoreWordWrap(menuItem)];
+
+/**
+ * returns true if XBARDarkMode is enabled.
+ * allways returns false if 'env' permission has not been previously granted.
+ */
+export const isDarkMode = async (): Promise<boolean> => {
+  const permissions = await Deno.permissions.query({ name: 'env' });
+  return permissions.state === 'granted'
+    ? Deno.env.get('XBARDarkMode') === 'true'
+    : false;
+};
diff --git a/src/format.js b/src/format.js
deleted file mode 100644
index d6447a9..0000000
--- a/src/format.js
+++ /dev/null
@@ -1,32 +0,0 @@
-import { pipe, pipeCompatibleReduce } from './utility.js';
-
-// line Object access layer
-const getText = (lineObj) => lineObj.text ?? '';
-const getSubMenuLevel = (lineObj) => lineObj.submenuLevel;
-// deno-lint-ignore no-unused-vars
-const ignoreSubMenuLevel = ({ submenuLevel, ...lineObj }) => lineObj;
-// deno-lint-ignore no-unused-vars
-const ignoreText = ({ text, ...lineObj }) => lineObj;
-
-// line formatting layer
-const getSubMenuFormatting = (lineObj) => '--'.repeat(getSubMenuLevel(lineObj));
-const getFormattedText = (lineObj) => `${getText(lineObj)}`.trim();
-const formatOutputOptions = pipeCompatibleReduce((output, [option, value]) =>
-  output.concat(` | ${option}=${value}`)
-)('');
-
-const getFormattedOutputOptions = pipe(
-  ignoreText,
-  ignoreSubMenuLevel,
-  Object.entries,
-  formatOutputOptions,
-);
-
-// entry layer
-export const formatLine = (lineObj) => {
-  const formattedLine = getSubMenuFormatting(lineObj) +
-    getFormattedText(lineObj) +
-    getFormattedOutputOptions(lineObj);
-  console.log(formattedLine);
-  return formattedLine;
-};
diff --git a/src/format.ts b/src/format.ts
new file mode 100644
index 0000000..e436310
--- /dev/null
+++ b/src/format.ts
@@ -0,0 +1,37 @@
+import { pipe, pipeCompatibleReduce } from './utility.ts';
+import { Menu } from './types.d.ts';
+
+// line Object access layer
+const getText = (lineObj: Menu) => lineObj.text ?? '';
+const getSubMenuLevel = (lineObj: Menu) => parseInt(`${lineObj.submenuLevel}`);
+
+// deno-lint-ignore no-unused-vars
+const ignoreSubMenuLevel = ({ submenuLevel, ...lineObj }: Menu) => lineObj;
+// deno-lint-ignore no-unused-vars
+const ignoreText = ({ text, ...lineObj }: Menu) => lineObj;
+
+// line formatting layer
+const getSubMenuFormatting = (lineObj: Menu) =>
+  '--'.repeat(getSubMenuLevel(lineObj));
+const getFormattedText = (lineObj: Menu) => `${getText(lineObj)}`.trim();
+
+const formatOutputOptions = pipeCompatibleReduce((
+  output: string,
+  [option, value]: string,
+) => output.concat(` | ${option}=${value}`))('');
+
+const getFormattedOutputOptions = pipe(
+  ignoreText,
+  ignoreSubMenuLevel,
+  Object.entries,
+  formatOutputOptions,
+);
+
+// entry layer
+export const formatLine = (lineObj: Menu) => {
+  const formattedLine = getSubMenuFormatting(lineObj) +
+    getFormattedText(lineObj) +
+    getFormattedOutputOptions(lineObj);
+  console.log(formattedLine);
+  return formattedLine;
+};
diff --git a/src/index.js b/src/index.js
deleted file mode 100644
index bc53ab1..0000000
--- a/src/index.js
+++ /dev/null
@@ -1,58 +0,0 @@
-import { pipe, pipeCompatibleMap } from './utility.js';
-import { wordWrap } from './accessibility.js';
-import { formatLine } from './format.js';
-
-// item layer
-const isSeparator = (item) => item === separator;
-
-const hasSubmenu = (item) => !!item.submenu;
-
-const getSubmenu = (item) =>
-  item.submenu.map((e) => ({
-    ...e,
-    submenuLevel: item.submenuLevel ? item.submenuLevel + 1 : 1,
-  }));
-
-// deno-lint-ignore no-unused-vars
-const ignoreSubmenu = ({ submenu, ...item }) => item;
-
-const formatItem = pipe(wordWrap, pipeCompatibleMap(formatLine));
-
-// array layer
-const addItem = (arr, item) => [
-  ...arr,
-  ...formatItem(item),
-];
-
-const addItemWithSubmenu = (arr, item) => [
-  ...addItem(arr, ignoreSubmenu(item)),
-  ...pipe(getSubmenu, xbar)(item),
-];
-
-const includeSeparator = (arr) => [
-  ...arr,
-  formatLine(separator),
-];
-
-//entry layer
-/**
- * Prints output to xbar and returns printed output as an array of strings
- * @param layout - array of xbar menu items
- * @returns {string[]} array of strings that were printed as menu items
- */
-export const xbar = (layout) =>
-  layout.reduce((menuItems, item) => {
-    switch (true) {
-      case (isSeparator(item)):
-        return includeSeparator(menuItems);
-      case (hasSubmenu(item)):
-        return addItemWithSubmenu(menuItems, item);
-      default:
-        return addItem(menuItems, item);
-    }
-  }, []);
-
-/** used for declaring a separator*/
-export const separator = {
-  text: '---',
-};
diff --git a/src/index.ts b/src/index.ts
new file mode 100644
index 0000000..249c117
--- /dev/null
+++ b/src/index.ts
@@ -0,0 +1,57 @@
+import { pipe, pipeCompatibleMap } from './utility.ts';
+import { wordWrap } from './accessibility.ts';
+import { formatLine } from './format.ts';
+import { Menu, MenuItem, MenuItemWithSubMenu } from './types.d.ts';
+
+// item layer
+//const isSeparator = (item:MenuItem) => item === separator;
+
+const hasSubmenu = (item: MenuItem) => !!item.submenu;
+
+const getSubmenu = (item: MenuItemWithSubMenu) =>
+  item.submenu.map((e) => ({
+    ...e,
+    submenuLevel: item.submenuLevel ? item.submenuLevel + 1 : 1,
+  }));
+
+// deno-lint-ignore no-unused-vars
+const ignoreSubmenu = ({ submenu, ...item }: MenuItem): Menu => item;
+
+const formatItem = pipe(wordWrap, pipeCompatibleMap(formatLine));
+
+// array layer
+const addItem = (arr: string[], item: Menu) => [
+  ...arr,
+  ...formatItem(item),
+];
+
+const addItemWithSubmenu = (arr: string[], item: MenuItem) => [
+  ...addItem(arr, ignoreSubmenu(item)),
+  ...pipe(getSubmenu, xbar)(item),
+];
+
+//const includeSeparator = (arr:MenuItem[]) => [
+// ...arr,
+// formatLine(separator),
+//];
+
+//entry layer
+/**
+ * Prints output to xbar and returns printed output as an array of strings
+ */
+export const xbar = (layout: MenuItem[]): string[] =>
+  layout.reduce((menuItems: string[], item) => {
+    switch (true) {
+      //   case (isSeparator(item)):
+      //    return includeSeparator(menuItems);
+      case (hasSubmenu(item)):
+        return addItemWithSubmenu(menuItems, item);
+      default:
+        return addItem(menuItems, item);
+    }
+  }, []);
+
+/** used for declaring a separator*/
+export const separator = {
+  text: '---',
+};
diff --git a/src/types.d.ts b/src/types.d.ts
new file mode 100644
index 0000000..a542fe0
--- /dev/null
+++ b/src/types.d.ts
@@ -0,0 +1,49 @@
+interface Menu {
+  text?: string;
+  color?: string;
+  wordWrap?: number;
+  size?: number;
+  submenuLevel?: number;
+  href?: string;
+  font?: string;
+  shell?: string;
+  terminal?: boolean;
+  refresh?: boolean;
+  dropdown?: boolean;
+  length?: number;
+  trim?: boolean;
+  alternate?: boolean;
+  templateImage?: string;
+  image?: string;
+  emojize?: boolean;
+  ansi?: boolean;
+  key?: string;
+  param1?: string;
+  param2?: string;
+  param3?: string;
+  param4?: string;
+  param5?: string;
+  param6?: string;
+  param7?: string;
+  param8?: string;
+  param9?: string;
+  param10?: string;
+}
+
+export interface MenuItem extends Menu {
+  submenu?: Menu[];
+}
+
+export interface MenuItemWithSubMenu extends Menu {
+  submenu: Menu[];
+}
+
+export interface MenuItemWithWordWrap extends Menu {
+  text: string;
+  wordWrap: number;
+}
+
+export type separator = {
+  text: '---';
+};
+export type Layout = Array<MenuItem | separator>;
diff --git a/src/utility.js b/src/utility.js
deleted file mode 100644
index f925d92..0000000
--- a/src/utility.js
+++ /dev/null
@@ -1,14 +0,0 @@
-export const pipe = (...functions) =>
-  (x) =>
-    functions.reduce(
-      (acc, fn) => fn(acc),
-      x,
-    );
-
-export const pipeCompatibleMap = (callback) => (target) => target.map(callback);
-export const pipeCompatibleReduce = (callback) =>
-  (initValue) => (target) => target.reduce(callback, initValue);
-export const pipeCompatibleSplit = (separator) =>
-  (target) => target.split(separator);
-export const pipeCompatibleFilter = (callback) =>
-  (target) => target.filter(callback);
diff --git a/src/utility.ts b/src/utility.ts
new file mode 100644
index 0000000..14671cc
--- /dev/null
+++ b/src/utility.ts
@@ -0,0 +1,27 @@
+// deno-lint-ignore ban-types
+export const pipe = (...functions: Function[]) =>
+  // deno-lint-ignore no-explicit-any
+  (x: any) =>
+    functions.reduce(
+      (acc, fn) => fn(acc),
+      x,
+    );
+
+export const pipeCompatibleSplit = (separator: string) =>
+  (target: string) => target.split(separator);
+
+export const pipeCompatibleMap = <T1, T2>(callback: (x: T1) => T2) =>
+  (target: Array<T1>) => target.map(callback);
+
+export const pipeCompatibleFilter = <T>(callback: (x: T) => boolean) =>
+  (target: Array<T>) => target.filter(callback);
+
+export const pipeCompatibleReduce = <T1, T2>(
+  callback: (
+    previousValue: T2,
+    currentValue: T1,
+    currentIndex: number,
+    array: T1[],
+  ) => T2,
+) =>
+  (initValue: T2) => (target: Array<T1>) => target.reduce(callback, initValue);
diff --git a/test/accessibility.test.js b/test/accessibility.test.js
index d1facb3..98401ce 100644
--- a/test/accessibility.test.js
+++ b/test/accessibility.test.js
@@ -1,5 +1,5 @@
 import { assertEquals } from 'https://deno.land/std@0.128.0/testing/asserts.ts';
-import { wordWrap } from '../src/accessibility.js';
+import { wordWrap } from '../src/accessibility.ts';
 
 Deno.test('wordWrap splits a string into an array of lines', () => {
   const input = {
diff --git a/test/format.test.js b/test/format.test.js
index ab620f1..aa2aeff 100644
--- a/test/format.test.js
+++ b/test/format.test.js
@@ -2,7 +2,7 @@ import {
   assert,
   assertEquals,
 } from 'https://deno.land/std@0.128.0/testing/asserts.ts';
-import { formatLine } from '../src/format.js';
+import { formatLine } from '../src/format.ts';
 Deno.test('formatLine returns a string', () => {
   const input = {
     text:
diff --git a/test/index.test.js b/test/index.test.js
index 71e6c72..f5fd9bc 100644
--- a/test/index.test.js
+++ b/test/index.test.js
@@ -2,7 +2,7 @@ import {
   assert,
   assertEquals,
 } from 'https://deno.land/std@0.128.0/testing/asserts.ts';
-import { separator, xbar } from '../src/index.js';
+import { separator, xbar } from '../src/index.ts';
 
 Deno.test('xbar returns separator as ---', () => {
   const input = [separator];