diff --git a/lib/node_modules/@stdlib/symbol/to-string-tag/README.md b/lib/node_modules/@stdlib/symbol/to-string-tag/README.md
new file mode 100644
index 000000000000..8e3decd7d4d6
--- /dev/null
+++ b/lib/node_modules/@stdlib/symbol/to-string-tag/README.md
@@ -0,0 +1,137 @@
+<!--
+
+@license Apache-2.0
+
+Copyright (c) 2018 The Stdlib Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+
+-->
+
+# ToStringTagSymbol
+
+> [`Symbol.toStringTag`][mdn-symbol] which specifies the default string tag for an object.
+
+<!-- Section to include introductory text. Make sure to keep an empty line after the intro `section` element and another before the `/section` close. -->
+
+<section class="intro">
+
+</section>
+
+<!-- /.intro -->
+
+<!-- Package usage documentation. -->
+
+<section class="usage">
+
+## Usage
+
+```javascript
+var ToStringTagSymbol = require( '@stdlib/symbol/to-string-tag' );
+```
+
+#### ToStringTagSymbol
+
+toStringTag [`symbol`][mdn-symbol] which specifies the default string tag used by Object.prototype.toString.
+
+```javascript
+var s = typeof ToStringTagSymbol;
+// e.g., returns 'symbol'
+```
+
+</section>
+
+<!-- /.usage -->
+
+<!-- Package usage notes. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="notes">
+
+## Notes
+
+-   The [symbol][mdn-symbol] is only supported in environments which support [symbols][mdn-symbol]. In non-supporting environments, the value is `null`.
+
+</section>
+
+<!-- /.notes -->
+
+<!-- Package usage examples. -->
+
+<section class="examples">
+
+## Examples
+
+<!-- eslint no-undef: "error" -->
+
+```javascript
+var ToStringTagSymbol = require( '@stdlib/symbol/to-string-tag' );
+
+function Foo() {
+    // Assign a property to avoid an empty function:
+    this.x = 1;
+}
+
+if ( ToStringTagSymbol ) {
+    Foo.prototype[ ToStringTagSymbol ] = 'FooObject';
+}
+
+var obj = new Foo();
+
+// When using Object.prototype.toString:
+console.log( Object.prototype.toString.call( obj ) );
+// => '[object FooObject]'
+```
+
+</section>
+
+<!-- /.examples -->
+
+<!-- Section to include cited references. If references are included, add a horizontal rule *before* the section. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="references">
+
+</section>
+
+<!-- /.references -->
+
+<!-- Section for related `stdlib` packages. Do not manually edit this section, as it is automatically populated. -->
+
+<section class="related">
+
+* * *
+
+## See Also
+
+-   <span class="package-name">[`@stdlib/symbol/ctor`][@stdlib/symbol/ctor]</span><span class="delimiter">: </span><span class="description">symbols.</span>
+
+</section>
+
+<!-- /.related -->
+
+<!-- Section for all links. Make sure to keep an empty line after the `section` element and another before the `/section` close. -->
+
+<section class="links">
+
+[mdn-symbol]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Symbol
+
+<!-- <related-links> -->
+
+[@stdlib/symbol/ctor]: https://github.com/stdlib-js/stdlib/tree/develop/lib/node_modules/%40stdlib/symbol/ctor
+
+<!-- </related-links> -->
+
+</section>
+
+<!-- /.links -->
+
+
diff --git a/lib/node_modules/@stdlib/symbol/to-string-tag/docs/repl.txt b/lib/node_modules/@stdlib/symbol/to-string-tag/docs/repl.txt
new file mode 100644
index 000000000000..0ce0e5ff0cde
--- /dev/null
+++ b/lib/node_modules/@stdlib/symbol/to-string-tag/docs/repl.txt
@@ -0,0 +1,15 @@
+{{alias}}
+    toStringTag symbol.
+
+    This symbol specifies the default tag used by Object.prototype.toString.
+
+    The symbol is only supported in ES6/ES2015+ environments. For non-supporting
+    environments, the value is `null`.
+
+    Examples
+    --------
+    > var s = {{alias}};
+
+    See Also
+    --------
+
diff --git a/lib/node_modules/@stdlib/symbol/to-string-tag/docs/types/index.d.ts b/lib/node_modules/@stdlib/symbol/to-string-tag/docs/types/index.d.ts
new file mode 100644
index 000000000000..5609fe2e7ce5
--- /dev/null
+++ b/lib/node_modules/@stdlib/symbol/to-string-tag/docs/types/index.d.ts
@@ -0,0 +1,30 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2021 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+// TypeScript Version: 4.1
+
+/**
+* toStringTag symbol.
+*
+* ## Notes
+*
+* -   This symbol specifies the default tag used by `Object.prototype.toString`.
+* -   The symbol is only supported in ES6/ES2015+ environments. For non-supporting environments, the value is `null`.
+*/
+export = Symbol.toStringTag;
+
diff --git a/lib/node_modules/@stdlib/symbol/to-string-tag/docs/types/test.ts b/lib/node_modules/@stdlib/symbol/to-string-tag/docs/types/test.ts
new file mode 100644
index 000000000000..84ed801212c6
--- /dev/null
+++ b/lib/node_modules/@stdlib/symbol/to-string-tag/docs/types/test.ts
@@ -0,0 +1,30 @@
+/*
+* @license Apache-2.0
+*
+* Copyright (c) 2021 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+/* eslint-disable @typescript-eslint/no-unused-expressions */
+
+import ToStringTagSymbol = require( './index' );
+
+
+// TESTS //
+
+// The exported value is the toStringTag symbol...
+{
+	ToStringTagSymbol;
+}
+
diff --git a/lib/node_modules/@stdlib/symbol/to-string-tag/examples/index.js b/lib/node_modules/@stdlib/symbol/to-string-tag/examples/index.js
new file mode 100644
index 000000000000..d1fdbd9faf43
--- /dev/null
+++ b/lib/node_modules/@stdlib/symbol/to-string-tag/examples/index.js
@@ -0,0 +1,35 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2018 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+var ToStringTagSymbol = require( './../lib' );
+
+function Person( name ) {
+	this.name = name;
+
+	// Set a custom tag used by Object.prototype.toString:
+	if ( ToStringTagSymbol ) {
+		this[ ToStringTagSymbol ] = 'Person';
+	}
+}
+
+var p = new Person( 'Alice' );
+
+console.log( Object.prototype.toString.call( p ) );
+// => '[object Person]'
diff --git a/lib/node_modules/@stdlib/symbol/to-string-tag/lib/index.js b/lib/node_modules/@stdlib/symbol/to-string-tag/lib/index.js
new file mode 100644
index 000000000000..b6975be8dae2
--- /dev/null
+++ b/lib/node_modules/@stdlib/symbol/to-string-tag/lib/index.js
@@ -0,0 +1,50 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2018 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+/**
+* ToStringTag symbol.
+*
+* @module @stdlib/symbol/to-string-tag
+*
+* @example
+* var ToStringTagSymbol = require( '@stdlib/symbol/to-string-tag' );
+*
+* function Person( name ) {
+*     this.name = name;
+*
+*     // Provide a custom `toString` tag:
+*     if ( ToStringTagSymbol ) {
+*         this[ ToStringTagSymbol ] = 'Person';
+*     }
+* }
+*
+* var p = new Person( 'Alice' );
+* console.log( Object.prototype.toString.call( p ) );
+* // => '[object Person]'
+*/
+
+// MAIN //
+
+var main = require( './main.js' );
+
+
+// EXPORTS //
+
+module.exports = main;
diff --git a/lib/node_modules/@stdlib/symbol/to-string-tag/lib/main.js b/lib/node_modules/@stdlib/symbol/to-string-tag/lib/main.js
new file mode 100644
index 000000000000..b6ffc9988224
--- /dev/null
+++ b/lib/node_modules/@stdlib/symbol/to-string-tag/lib/main.js
@@ -0,0 +1,56 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2018 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var hasToStringTagSupport = require( '@stdlib/assert/has-tostringtag-support' );
+
+
+// MAIN //
+
+/**
+* ToStringTag symbol.
+*
+* @name ToStringTagSymbol
+* @constant
+* @type {(symbol|null)}
+*
+* @example
+* function Person( name ) {
+*     this.name = name;
+*
+*     // Provide a custom `toString` tag:
+*     if ( ToStringTagSymbol ) {
+*         this[ ToStringTagSymbol ] = 'Person';
+*     }
+* }
+*
+* var p = new Person( 'Alice' );
+* console.log( Object.prototype.toString.call( p ) );
+* // => '[object Person]'
+*/
+var ToStringTagSymbol = ( hasToStringTagSupport() ) ?
+	Symbol.toStringTag :
+	null;
+
+
+// EXPORTS //
+
+module.exports = ToStringTagSymbol;
diff --git a/lib/node_modules/@stdlib/symbol/to-string-tag/package.json b/lib/node_modules/@stdlib/symbol/to-string-tag/package.json
new file mode 100644
index 000000000000..5eebd45b98a9
--- /dev/null
+++ b/lib/node_modules/@stdlib/symbol/to-string-tag/package.json
@@ -0,0 +1,59 @@
+{
+  "name": "@stdlib/symbol/to-string-tag",
+  "version": "0.0.0",
+  "description": "Symbol.toStringTag.",
+  "license": "Apache-2.0",
+  "author": {
+    "name": "The Stdlib Authors",
+    "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+  },
+  "contributors": [
+    {
+      "name": "The Stdlib Authors",
+      "url": "https://github.com/stdlib-js/stdlib/graphs/contributors"
+    }
+  ],
+  "main": "./lib",
+  "directories": {
+    "doc": "./docs",
+    "example": "./examples",
+    "lib": "./lib",
+    "test": "./test"
+  },
+  "types": "./docs/types",
+  "scripts": {},
+  "homepage": "https://github.com/stdlib-js/stdlib",
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/stdlib-js/stdlib.git"
+  },
+  "bugs": {
+    "url": "https://github.com/stdlib-js/stdlib/issues"
+  },
+  "dependencies": {},
+  "devDependencies": {},
+  "engines": {
+    "node": ">=0.10.0",
+    "npm": ">2.7.0"
+  },
+  "os": [
+    "aix",
+    "darwin",
+    "freebsd",
+    "linux",
+    "macos",
+    "openbsd",
+    "sunos",
+    "win32",
+    "windows"
+  ],
+  "keywords": [
+    "stdlib",
+    "symbol",
+    "sym",
+    "to-string-tag",
+    "object",
+    "string-tag",
+    "tag"
+  ]
+}
diff --git a/lib/node_modules/@stdlib/symbol/to-string-tag/test/test.js b/lib/node_modules/@stdlib/symbol/to-string-tag/test/test.js
new file mode 100644
index 000000000000..985b6f19cd96
--- /dev/null
+++ b/lib/node_modules/@stdlib/symbol/to-string-tag/test/test.js
@@ -0,0 +1,52 @@
+/**
+* @license Apache-2.0
+*
+* Copyright (c) 2018 The Stdlib Authors.
+*
+* Licensed under the Apache License, Version 2.0 (the "License");
+* you may not use this file except in compliance with the License.
+* You may obtain a copy of the License at
+*
+*    http://www.apache.org/licenses/LICENSE-2.0
+*
+* Unless required by applicable law or agreed to in writing, software
+* distributed under the License is distributed on an "AS IS" BASIS,
+* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+* See the License for the specific language governing permissions and
+* limitations under the License.
+*/
+
+'use strict';
+
+// MODULES //
+
+var tape = require( 'tape' );
+var hasToStringTagSupport = require( '@stdlib/assert/has-tostringtag-support' );
+var isSymbol = require( '@stdlib/assert/is-symbol' );
+var Sym = require( './../lib' );
+
+
+// VARIABLES //
+
+var opts = {
+	'skip': !hasToStringTagSupport()
+};
+
+
+// TESTS //
+
+tape( 'main export is a symbol in supporting environments (ES6/2015+) or otherwise null', function test( t ) {
+	t.ok( true, __filename );
+	if ( opts.skip ) {
+		t.strictEqual( Sym, null, 'main export is null' );
+	} else {
+		t.strictEqual( typeof Sym, 'symbol', 'main export is a symbol' );
+		t.strictEqual( isSymbol( Sym ), true, 'main export is a symbol' );
+	}
+	t.end();
+});
+
+tape( 'the main export is an alias for `Symbol.toStringTag`', opts, function test( t ) {
+	t.strictEqual( Sym, Symbol.toStringTag, 'is an alias' );
+	t.end();
+});