diff --git a/bin/tldr b/bin/tldr
index f0f5c74..d85507c 100755
--- a/bin/tldr
+++ b/bin/tldr
@@ -7,6 +7,8 @@ const config = require('../lib/config');
 const platform = require('../lib/platform');
 const { TldrError } = require('../lib/errors');
 
+const { Option } = program;
+
 program
   .version(pkg.version, '-v, --version', 'Display version')
   .helpOption('-h, --help', 'Show this help message')
@@ -20,15 +22,18 @@ program
   .option('-1, --single-column', 'List single command per line (use with options -l or -a)')
   .option('-r, --random', 'Show a random command')
   .option('-e, --random-example', 'Show a random example')
-  .option('-f, --render [file]', 'Render a specific markdown [file]')
+  .option('-f, --render <file>', 'Render a specific markdown [file]')
   .option('-m, --markdown', 'Output in markdown format')
-  .option('-o, --os [type]', 'Override the operating system [linux, osx, sunos, windows]')
+  .addOption(
+    new Option('-o, --os <type>', 'Override the operating system [linux, osx, sunos, windows]')
+      .choices(['linux', 'osx', 'sunos', 'windows'])
+  )
   .option('--linux', 'Override the operating system with Linux')
   .option('--osx', 'Override the operating system with OSX')
   .option('--sunos', 'Override the operating system with SunOS')
   .option('--windows', 'Override the operating system with Windows')
-  .option('-t, --theme [theme]', 'Color theme (simple, base16, ocean)')
-  .option('-s, --search [keywords]', 'Search pages using keywords')
+  .option('-t, --theme <theme>', 'Color theme (simple, base16, ocean)')
+  .option('-s, --search <keywords>', 'Search pages using keywords')
   //
   // CACHE MANAGEMENT
   //
@@ -60,60 +65,59 @@ program.on('--help', () => {
   console.log(help);
 });
 
-program.parse(process.argv);
+const options = program.parse(process.argv).opts();
 
-if (program.linux) {
-  program.os = 'linux';
+if (options.linux) {
+  options.os = 'linux';
 }
 
-if (program.osx) {
-  program.os = 'osx';
+if (options.osx) {
+  options.os = 'osx';
 }
 
-if (program.sunos) {
-  program.os = 'sunos';
+if (options.sunos) {
+  options.os = 'sunos';
 }
 
-if (program.windows) {
-  program.os = 'windows';
+if (options.windows) {
+  options.os = 'windows';
 }
 
 let cfg = config.get();
-if (program.os) {
-  if (platform.isSupported(program.os)) {
-    cfg.platform = program.os;
+if (options.os) {
+  if (platform.isSupported(options.os)) {
+    cfg.platform = options.os;
   }
 }
 
-if (program.theme) {
-  cfg.theme = program.theme;
+if (options.theme) {
+  cfg.theme = options.theme;
 }
 
 const tldr = new Tldr(cfg);
 
 let p = null;
-if (program.list) {
-  p = tldr.list(program.singleColumn);
-} else if (program.listAll) {
-  p = tldr.listAll(program.singleColumn);
-} else if (program.random) {
-  p = tldr.random(program);
-} else if (program.randomExample) {
+if (options.list) {
+  p = tldr.list(options.singleColumn);
+} else if (options.listAll) {
+  p = tldr.listAll(options.singleColumn);
+} else if (options.random) {
+  p = tldr.random(options);
+} else if (options.randomExample) {
   p = tldr.randomExample();
-} else if (program.clearCache) {
+} else if (options.clearCache) {
   p = tldr.clearCache();
-} else if (program.update) {
+} else if (options.update) {
   p = tldr.updateCache()
     .then(() => {
       return tldr.updateIndex();
     });
-} else if (program.render) {
-  p = tldr.render(program.render);
-} else if (program.search) {
-  program.args.unshift(program.search);
-  p = tldr.search(program.args);
+} else if (options.render) {
+  p = tldr.render(options.render);
+} else if (options.search) {
+  p = tldr.search([ options.search, ...program.args ]);
 } else if (program.args.length >= 1) {
-  p = tldr.get(program.args, program);
+  p = tldr.get(program.args, options);
 }
 
 if (p === null) {
diff --git a/lib/errors.js b/lib/errors.js
index 882c4e5..fc1c511 100644
--- a/lib/errors.js
+++ b/lib/errors.js
@@ -35,20 +35,10 @@ If you want to contribute it, feel free to send a pull request to: ${repo}
   }
 }
 
-class MissingRenderPathError extends TldrError {
-  constructor() {
-    super('Option --render needs an argument.');
-    this.name = 'MissingRenderPathError';
-    // eslint-disable-next-line no-magic-numbers
-    this.code = 4;
-  }
-}
-
 module.exports = {
   TldrError,
   EmptyCacheError,
-  MissingPageError,
-  MissingRenderPathError
+  MissingPageError
 };
 
 function trim(strings, ...values) {
diff --git a/lib/tldr.js b/lib/tldr.js
index 823e0fc..3c0ffcb 100644
--- a/lib/tldr.js
+++ b/lib/tldr.js
@@ -4,7 +4,7 @@ const sample = require('lodash/sample');
 const fs = require('fs-extra');
 const ms = require('ms');
 const ora = require('ora');
-const { EmptyCacheError, MissingPageError, MissingRenderPathError } = require('./errors');
+const { EmptyCacheError, MissingPageError } = require('./errors');
 const Cache = require('./cache');
 const search = require('./search');
 const platform = require('./platform');
@@ -73,9 +73,6 @@ class Tldr {
   }
 
   render(file) {
-    if (typeof file !== 'string') {
-      throw new MissingRenderPathError();
-    }
     return fs.readFile(file, 'utf8')
       .then((content) => {
         // Getting the shortindex first to populate the shortindex var
diff --git a/package-lock.json b/package-lock.json
index 4d736c1..7dd9d20 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1499,9 +1499,9 @@
       "dev": true
     },
     "commander": {
-      "version": "6.1.0",
-      "resolved": "https://registry.npmjs.org/commander/-/commander-6.1.0.tgz",
-      "integrity": "sha512-wl7PNrYWd2y5mp1OK/LhTlv8Ff4kQJQRXXAvF+uU/TPNiVJUxZLRYGj/B0y/lPGAVcSbJqH2Za/cvHmrPMC8mA=="
+      "version": "8.0.0",
+      "resolved": "https://registry.npmjs.org/commander/-/commander-8.0.0.tgz",
+      "integrity": "sha512-Xvf85aAtu6v22+E5hfVoLHqyul/jyxh91zvqk/ioJTQuJR7Z78n7H558vMPKanPSRgIEeZemT92I2g9Y8LPbSQ=="
     },
     "commondir": {
       "version": "1.0.1",
diff --git a/package.json b/package.json
index df87350..dcdeb9e 100644
--- a/package.json
+++ b/package.json
@@ -52,7 +52,7 @@
   "dependencies": {
     "axios": "^0.21.1",
     "chalk": "^4.1.0",
-    "commander": "^6.1.0",
+    "commander": "^8.0.0",
     "fs-extra": "^9.0.1",
     "glob": "^7.1.6",
     "lodash": "^4.17.20",