diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 086a0422661b..fa6650e420d7 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -2,7 +2,7 @@
 
 ----
 
-<p align="center">
+<p align="center" class="toc">
    <strong><a href="#setup">Setup</a></strong>
    |
    <strong><a href="#running-lintingtests">Running linting/tests</a></strong>
@@ -27,7 +27,7 @@ Contributions are always welcome, no matter how large or small.
 
 - If you aren't just making a documentation change, you'll probably want to learn a bit about a few topics.
  - [ASTs](https://en.wikipedia.org/wiki/Abstract_syntax_tree) (Abstract Syntax Tree): The Babel AST [spec](https://github.com/babel/babylon/blob/master/ast/spec.md) is a bit different from [ESTree](https://github.com/estree/estree). The differences are listed [here](https://github.com/babel/babylon#output).
- - This repository's [`/doc`](/doc) directory for notes on Babel's internals
+ - This repository's [`/doc`](https://github.com/babel/babel/tree/master/doc) directory for notes on Babel's internals
  - Check out [the Babel Plugin Handbook](https://github.com/thejameskyle/babel-handbook/blob/master/translations/en/plugin-handbook.md#babel-plugin-handbook) - core plugins are written the same way as any other plugin!
  - Check out [AST Explorer](http://astexplorer.net/#/scUfOmVOG5) to learn more about ASTs or make your own plugin in the browser
 - When you feel ready to finally jump into the babel source code a good start is to look out for issues which are labeled with [help-wanted](https://github.com/babel/babel/issues?q=is%3Aissue+is%3Aopen+label%3A%22help+wanted%22) and/or [beginner-friendly](https://github.com/babel/babel/issues?q=is%3Aissue+is%3Aopen+label%3A%22beginner-friendly%22).
@@ -47,7 +47,7 @@ You can check this with `node -v` and `npm -v`.
 In addition, make sure that Yarn is installed.
 Installation instructions can be found here: https://yarnpkg.com/en/docs/install.
 
-#### Setup
+### Setup
 
 ```sh
 $ git clone https://github.com/babel/babel
@@ -77,7 +77,7 @@ If you wish to build a copy of Babel for distribution, then run:
 $ make build-dist
 ```
 
-#### Running linting/tests
+### Running linting/tests
 
 You can run lint via:
 
@@ -108,7 +108,7 @@ $ make test-only
 
 Most likely you'll want to focus in on a specific issue.
 
-To run tests for a specific package in [packages](/packages), you can use the `TEST_ONLY` environment variable:
+To run tests for a specific package in [packages](https://github.com/babel/babel/tree/master/packages), you can use the `TEST_ONLY` environment variable:
 
 ```sh
 $ TEST_ONLY=babel-cli make test
@@ -133,27 +133,27 @@ $ BABEL_ENV=cov make build
 $ ./scripts/test-cov.sh
 ```
 
-#### Writing tests
+### Writing tests
 
-Most packages in [`/packages`](/packages) have a `test` folder, however some tests might be in other packages or in [`/packages/babel-core`](/packages/babel-core/test/fixtures).
+Most packages in [`/packages`](https://github.com/babel/babel/tree/master/packages) have a `test` folder, however some tests might be in other packages or in [`/packages/babel-core`](https://github.com/babel/babel/tree/master/packages/babel-core/test/fixtures).
 
-##### `babel-plugin-x`
+#### `babel-plugin-x`
 
 All the Babel plugins (and other packages) that have a `/test/fixtures` are written in a similar way.
 
-For example, in [`babel-plugin-transform-exponentiation-operator/test`](/packages/babel-plugin-transform-exponentiation-operator/test):
+For example, in [`babel-plugin-transform-exponentiation-operator/test`](https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-exponentiation-operator/test):
 
-- There is an `index.js` file. It imports our [test helper](/packages/babel-helper-plugin-test-runner). (You don't have to worry about this).
-- There can be multiple folders under [`/fixtures`](/packages/babel-plugin-transform-exponentiation-operator/test/fixtures)
-   - There is an [`options.json`](/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/options.json) file whose function is similar to a `.babelrc` file, allowing you to pass in the plugins and settings you need for your tests.
+- There is an `index.js` file. It imports our [test helper](https://github.com/babel/babel/tree/master/packages/babel-helper-plugin-test-runner). (You don't have to worry about this).
+- There can be multiple folders under [`/fixtures`](https://github.com/babel/babel/tree/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures)
+   - There is an [`options.json`](https://github.com/babel/babel/blob/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/options.json) file whose function is similar to a `.babelrc` file, allowing you to pass in the plugins and settings you need for your tests.
    - For this test, we only need the relevant plugin, so it's just `{ "plugins": ["transform-exponentiation-operator"] }`.
    - If necessary, you can have an `options.json` with different options in each subfolder.
 
 - In each subfolder, you can organize your directory structure by categories of tests. (Example: these folders can be named after the feature you are testing or can reference the issue number they fix)
 - Generally, there are two kinds of tests for plugins
-   - The first is a simple test of the input and output produced by running Babel on some code. We do this by creating an [`actual.js`](packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/binary/actual.js) file and an [`expected.js`](/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/binary/expected.js) file.
+   - The first is a simple test of the input and output produced by running Babel on some code. We do this by creating an [`actual.js`](https://github.com/babel/babel/blob/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/binary/actual.js) file and an [`expected.js`](https://github.com/babel/babel/blob/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/binary/expected.js) file.
    - If you need to expect an error, you can ignore creating the `expected.js` file and pass a new `throws` key to the `options.json` that contains the error string that is created.
-   - The second and preferred type is a test that actually evaluates the produced code and asserts that certain properties are true or false. We do this by creating an [`exec.js`](/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/comprehensive/exec.js) file.
+   - The second and preferred type is a test that actually evaluates the produced code and asserts that certain properties are true or false. We do this by creating an [`exec.js`](https://github.com/babel/babel/blob/master/packages/babel-plugin-transform-exponentiation-operator/test/fixtures/exponentian-operator/comprehensive/exec.js) file.
 
 In an actual/expected test, you simply write out the code you want transformed in `actual.js`.
 
@@ -186,7 +186,7 @@ If you need to check for an error that is thrown you can add to the `options.jso
 }
 ```
 
-##### Bootstrapping expected output
+#### Bootstrapping expected output
 
 For both `babel-plugin-x` and `babylon`, you can easily generate an `expected.js`/`expected.json` automatically by just providing `actual.js` and running the tests as you usually would.
 
@@ -202,7 +202,7 @@ For both `babel-plugin-x` and `babylon`, you can easily generate an `expected.js
             - expected.json (will be generated if not created)
 ```
 
-#### Debugging code
+### Debugging code
 
 A common approach to debugging JavaScript code is to walk through the code using the [Chrome DevTools](https://developers.google.com/web/tools/chrome-devtools/) debugger.
 For illustration purposes, we are going to assume that we need to get a better understanding of [`Generator.generate()`](https://github.com/babel/babel/blob/b5246994b57f06af871be6a63dcc4c6fd41d94d6/packages/babel-generator/src/index.js#L32), which is responsible for generating code for a given AST.
@@ -239,9 +239,9 @@ The debugger starts at the first executed line of code, which is Mocha's first l
 Click _Resume script execution_ <img src="https://i.imgur.com/TmYBn9d.png" alt="Resume script execution button." width="16"> to jump to the set breakpoint.
 Note that the code shown in Chrome DevTools is compiled code and therefore differs.
 
-#### Internals
+## Internals
 - AST spec ([babylon/ast/spec.md](https://github.com/babel/babylon/blob/master/ast/spec.md))
-- Versioning ([doc/design/versioning.md](./doc/design/versioning.md))
-- Monorepo ([doc/design/monorepo.md](./doc/design/monorepo.md))
-- Compiler environment support ([doc/design/compiler-environment-support.md](./doc/design/compiler-environment-support.md))
-- Compiler assumptions ([doc/design/compiler-assumptions.md](./doc/design/compiler-assumptions.md))
+- Versioning ([doc/design/versioning.md](https://github.com/babel/babel/blob/master/doc/design/versioning.md)
+- Monorepo ([doc/design/monorepo.md](https://github.com/babel/babel/blob/master/doc/design/monorepo.md))
+- Compiler environment support ([doc/design/compiler-environment-support.md](https://github.com/babel/babel/blob/master/doc/design/compiler-environment-support.md))
+- Compiler assumptions ([doc/design/compiler-assumptions.md](https://github.com/babel/babel/blob/master/doc/design/compiler-assumptions.md))