diff --git a/.gitignore b/.gitignore
index 38efa6caa2..d0ba1dbc90 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,9 +17,6 @@ lib-cov
 # Coverage directory used by tools like istanbul
 coverage
 
-# nyc test coverage
-.nyc_output
-
 # Grunt intermediate storage (http://gruntjs.com/creating-plugins#storing-task-files)
 .grunt
 
diff --git a/package.json b/package.json
index 426f1a9649..6eb4265682 100644
--- a/package.json
+++ b/package.json
@@ -5,7 +5,7 @@
   "main": "index.js",
   "scripts": {
     "dev": "node server.js",
-    "dev:debug": "node --inspect server.js",
+    "debug": "node --inspect-brk server.js",
     "build": "next build",
     "test": "jest",
     "start": "NODE_ENV=production node server.js",
diff --git a/pages/doc.js b/pages/doc.js
index 340ddd1f91..96184ba4e0 100644
--- a/pages/doc.js
+++ b/pages/doc.js
@@ -60,7 +60,7 @@ export default function Documentation({ item, headings, markdown, errorCode }) {
           apiKey: '755929839e113a981f481601c4f52082',
           indexName: 'dvc',
           inputSelector: '#doc-search',
-          debug: false // Set debug to true if you want to inspect the dropdown
+          debug: false // Set to `true` if you want to inspect the dropdown
         })
       }
     } catch (ReferenceError) {
@@ -81,7 +81,7 @@ export default function Documentation({ item, headings, markdown, errorCode }) {
     return () => Router.events.off('routeChangeComplete', handleRouteChange)
   }, [])
 
-  const githubLink = `https://github.com/iterative/dvc.org/blob/master${source}`
+  const githubLink = `https://github.com/iterative/dvc.org/blob/master/public${source}`
 
   return (
     <Page stickHeader={true}>
diff --git a/public/static/docs/command-reference/checkout.md b/public/static/docs/command-reference/checkout.md
index 0f807ef1be..829f1b1602 100644
--- a/public/static/docs/command-reference/checkout.md
+++ b/public/static/docs/command-reference/checkout.md
@@ -6,7 +6,7 @@ DVC-files.
 ## Synopsis
 
 ```usage
-usage: dvc checkout [-h] [-q | -v] [-d] [-f] [-R]
+usage: dvc checkout [-h] [-q | -v] [-d] [-R] [-f] [--relink]
                     [targets [targets ...]]
 
 positional arguments:
@@ -16,46 +16,38 @@ positional arguments:
 
 ## Description
 
-[DVC-files](/doc/user-guide/dvc-file-format) in a <abbr>project</abbr> specify
-which instance of each data file or directory should be used, with the checksums
-saved in the `outs` field. The `dvc checkout` command updates the workspace data
-to match with the <abbr>cached</abbr> files that correspond to those checksums.
-
-Using an SCM like Git, the DVC-files are kept under version control. At a given
-branch or tag of the SCM repository, the DVC-files will contain checksums for
-the corresponding data files kept in the cache. After an SCM command like
-`git checkout` is run, the DVC-files will change to the state at the specified
-branch or commit or tag. Afterwards, the `dvc checkout` command is required in
-order to synchronize the data files with the currently checked out DVC-files.
-
-This command must be executed after `git checkout` since Git doesn't track files
-that are under DVC control. For convenience a Git hook is available, simply by
-running `dvc install`, that will automate running `dvc checkout` after
-`git checkout`. See `dvc install` for more information.
-
-The execution of `dvc checkout` does:
-
-- Scan the `outs` entries in DVC-files to compare with the currently checked out
-  data files. The scanned DVC-files is limited by the listed `targets` (if any)
-  on the command line. And if the `--with-deps` option is specified, it scans
-  backward from the given `targets` in the corresponding
-  [pipeline](/doc/command-reference/pipeline).
-
-- For any data files where the checksum doesn't match their DVC-file entry, the
-  data file is restored from the cache. The link strategy used (`reflink`,
-  `hardlink`, `symlink`, or `copy`) depends on the OS and the configured value
-  for `cache.type` – See `dvc config cache`.
-
-Note that this command by default tries NOT to copy files between the cache and
-the workspace, using reflinks instead when supported by the file system. (Refer
-to
+[DVC-files](/doc/user-guide/dvc-file-format) act as pointers to specific version
+of data files or directories under DVC control. This command synchronizes the
+workspace data with the versions specified in the current DVC-files.
+
+`dvc checkout` is useful, for example, when using Git in the
+<abbr>project</abbr>, after `git clone`, `git checkout`, or any other operation
+that changes the DVC-files in the workspace.
+
+💡 For convenience, a Git hook is available to automate running `dvc checkout`
+after `git checkout`. Use `dvc install` to install it.
+
+The execution of `dvc checkout` does the following:
+
+- Scans the DVC-files to compare against the data files or directories in the
+  <abbr>workspace</abbr>. DVC knows which data (<abbr>outputs</abbr>) match
+  because their checksums are saved in the `outs` fields inside the DVC-files.
+  Scanning is limited to the given `targets` (if any). See also options
+  `--with-deps` and `--recursive` below.
+
+- Missing data files or directories, or those that don't match with any
+  DVC-file, are restored from the <abbr>cache</abbr>. See options `--force` and
+  `--relink`.
+
+By default, this command tries not to copy files between the cache and the
+workspace, using reflinks instead, when supported by the file system. (Refer to
 [File link types](/doc/user-guide/large-dataset-optimization#file-link-types-for-the-dvc-cache).)
 The next linking strategy default value is `copy` though, so unless other file
 link types are manually configured in `cache.type` (using `dvc config`), files
 will be copied. Keep in mind that having file copies doesn't present much of a
 negative impact unless the project uses very large data (several GBs or more).
-But leveraging file links is crucial for large files where checking out a 50Gb
-by copying file might take a few minutes for example, whereas with links,
+But leveraging file links is crucial with large files, for example when checking
+out a 50Gb file by copying might take a few minutes whereas, with links,
 restoring any file size will be almost instantaneous.
 
 > When linking files takes longer than expected (10 seconds for any one file)
@@ -63,13 +55,10 @@ restoring any file size will be almost instantaneous.
 > the faster link types available. These warnings can be turned off setting the
 > `cache.slow_link_warning` config option to `false` with `dvc config cache`.
 
-The output of `dvc checkout` does not list which data files were restored. It
-does report removed files and files that DVC was unable to restore because
-they're missing from the <abbr>cache</abbr>.
-
 This command will fail to checkout files that are missing from the cache. In
-such a case, `dvc checkout` prints a warning message. Any files that can be
-checked out without error will be restored.
+such a case, `dvc checkout` prints a warning message. It also lists removed
+files. Any files that can be checked out without error will be restored without
+being reported individually.
 
 There are two methods to restore a file missing from the cache, depending on the
 situation. In some cases a pipeline must be reproduced (using `dvc repro`) to
@@ -94,6 +83,12 @@ be pulled from remote storage using `dvc pull`.
   remove files that don't match those DVC-file references or are missing from
   cache. (They are not "committed", in DVC terms.)
 
+- `--relink` - ensures the file linking strategy (`reflink`, `hardlink`,
+  `symlink`, or `copy`) for all data in the workspace is consistent with the
+  project's [`cache.type`](/doc/command-reference/config#cache). This is
+  achieved by restoring **all data files or a directories** referenced in
+  current DVC-files (regardless of whether they match a current DVC-file).
+
 - `-h`, `--help` - shows the help message and exit.
 
 - `-q`, `--quiet` - do not write anything to standard output. Exit with 0 if no
@@ -210,18 +205,21 @@ do `dvc fetch` + `dvc checkout`.
 
 ## Automating `dvc checkout`
 
-We have the data files (managed by DVC) lined up with the other files (managed
-by Git). This required us to remember to run `dvc checkout`, and of course we
-won't always remember to do so. Wouldn't it be nice to automate this?
+We want the data files or directories (managed by DVC) to match with the other
+files (managed by Git e.g. source code). This requires us to remember running
+`dvc checkout` when needed, and of course we won't always remember to do so.
+Wouldn't it be nice to automate this?
 
-Let's run this command:
+Let's try this:
 
 ```dvc
 $ dvc install
 ```
 
-This installs Git hooks to automate running `dvc checkout` (or `dvc status`)
-when needed. Then we can checkout the master branch again:
+`dvc install` installs Git hooks to automate common operations, including
+running `dvc checkout` when needed.
+
+We can then checkout the master branch again:
 
 ```dvc
 $ git checkout bigrams
@@ -233,6 +231,6 @@ $ md5 model.pkl
 MD5 (model.pkl) = 3863d0e317dee0a55c4e59d2ec0eef33
 ```
 
-Previously this took two steps, `git checkout` followed by `dvc checkout`. We
-can now skip the second one, which is automatically executed for us. The
-workspace is automatically synchronized accordingly.
+Previously this took two commands, `git checkout` followed by `dvc checkout`. We
+can now skip the second one, which is automatically run for us. The workspace is
+automatically synchronized accordingly.
diff --git a/public/static/docs/command-reference/config.md b/public/static/docs/command-reference/config.md
index 02285e9ab4..59ee19a932 100644
--- a/public/static/docs/command-reference/config.md
+++ b/public/static/docs/command-reference/config.md
@@ -139,6 +139,10 @@ for more details.) This section contains the following options:
   [File link types](/doc/user-guide/large-dataset-optimization#file-link-types-for-the-dvc-cache)
   for a full explanation of each one.
 
+  To apply changes to this option in the workspace, by restoring all file
+  links/copies from cache, please use `dvc checkout --relink`. See
+  [checkout options](/doc/command-reference/checkout#options) for more details.
+
 - `cache.slow_link_warning` - used to turn off the warnings about having a slow
   cache link type. These warnings are thrown by `dvc pull` and `dvc checkout`
   when linking files takes longer than usual, to remind them that there are
diff --git a/public/static/docs/command-reference/remote/index.md b/public/static/docs/command-reference/remote/index.md
index 9856561927..7e018cd6e7 100644
--- a/public/static/docs/command-reference/remote/index.md
+++ b/public/static/docs/command-reference/remote/index.md
@@ -95,13 +95,13 @@ url = /path/to/remote
 remote = myremote
 ```
 
-## Example: Add Amazon S3 remote and modify its region
+## Example: Add a default Amazon S3 remote and modify its region
 
 > 💡 Before adding an S3 remote, be sure to
 > [Create a Bucket](https://docs.aws.amazon.com/AmazonS3/latest/gsg/CreatingABucket.html).
 
 ```dvc
-$ dvc remote add mynewremote s3://mybucket/myproject
+$ dvc remote add -d mynewremote s3://mybucket/myproject
 $ dvc remote modify mynewremote region us-east-2
 ```
 
diff --git a/public/static/docs/command-reference/repro.md b/public/static/docs/command-reference/repro.md
index a990c2b76c..729645abbd 100644
--- a/public/static/docs/command-reference/repro.md
+++ b/public/static/docs/command-reference/repro.md
@@ -45,6 +45,38 @@ files, intermediate or final results. It saves all the data files, intermediate
 or final results into the <abbr>DVC cache</abbr> (unless `--no-commit` option is
 specified), and updates stage files with the new checksum information.
 
+### Parallel stage execution
+
+Currently, `dvc repro` is not able to parallelize stage execution automatically.
+If you need to do this, you can launch `dvc repro` multiple times manually. For
+example, let's say a <abbr>pipeline</abbr> graph looks something like this:
+
+```
+$ dvc pipeline show --ascii result.py
++--------+          +--------+
+| A1.dvc |          | B1.dvc |
++--------+          +--------+
+     *                   *
+     *                   *
+     *                   *
++--------+          +--------+
+| A2.dvc |          | B2.dvc |
++--------+          +--------+
+          *         *
+           **     **
+             *   *
+        +------------+
+        | result.dvc |
+        +------------+
+```
+
+This pipeline consists of two parallel branches (`A` and `B`), and the final
+"result" stage, where the branches merge. To reproduce both branches at the same
+time, you could run `dvc repro A2.dvc` and `dvc repro B2.dvc` at the same time
+(e.g. in separate terminals). After both finish successfully, you can then run
+`dvc repro result.dvc`: DVC will know that both branches are already up-to-date
+and only execute the final stage.
+
 ## Options
 
 - `-f`, `--force` - reproduce a pipeline, regenerating its results, even if no
diff --git a/public/static/docs/sidebar.json b/public/static/docs/sidebar.json
index c92333fbb3..c253134e83 100644
--- a/public/static/docs/sidebar.json
+++ b/public/static/docs/sidebar.json
@@ -30,7 +30,6 @@
     ]
   },
   {
-    "label": "Install",
     "slug": "install",
     "source": "install/index.md",
     "children": [
@@ -140,7 +139,7 @@
       {
         "label": "Contributing",
         "slug": "contributing",
-        "source": "contributing/index.md",
+        "source": false,
         "children": [
           {
             "label": "DVC Core Project",
@@ -356,8 +355,8 @@
     ]
   },
   {
-    "label": "Understanding DVC",
     "slug": "understanding-dvc",
+    "label": "Understanding DVC",
     "source": false,
     "children": [
       "collaboration-issues",
diff --git a/public/static/docs/understanding-dvc/related-technologies.md b/public/static/docs/understanding-dvc/related-technologies.md
index 2dd2cb7c57..bf5dffa5bf 100644
--- a/public/static/docs/understanding-dvc/related-technologies.md
+++ b/public/static/docs/understanding-dvc/related-technologies.md
@@ -100,11 +100,11 @@ http://studio.ml/
 - Git-annex is a datafile-centric system whereas DVC is focused on providing a
   workflow for machine learning and reproducible experiments. When a DVC or
   Git-annex repository is cloned via `git clone`, data files won't be copied to
-  the local machine as file contents are stored in separate
+  the local machine, as file contents are stored in separate
   [remotes](/doc/command-reference/remote). With DVC,
-  [DVC-files](/doc/user-guide/dvc-file-format) (that provide the reproducible
-  workflow) are always included in the Git repository and hence can be recreated
-  locally with minimal effort.
+  [DVC-files](/doc/user-guide/dvc-file-format), which provide the reproducible
+  workflow, are always included in the Git repository. Hence, they can be
+  executed locally with minimal effort.
 
 - DVC is not fundamentally bound to Git, and users have the option of changing
   the repository format.
diff --git a/public/static/docs/user-guide/contributing/docs.md b/public/static/docs/user-guide/contributing/docs.md
index 28ac6cd4c1..496ecdc5e5 100644
--- a/public/static/docs/user-guide/contributing/docs.md
+++ b/public/static/docs/user-guide/contributing/docs.md
@@ -88,8 +88,8 @@ documentation files automatically.
 
 ### Debugging
 
-The `yarn dev:debug` script runs the local development server with Node's
-[`--inspect` option](https://nodejs.org/en/docs/guides/debugging-getting-started/#command-line-options)
+The `yarn debug` script runs the local development server with `node`'s
+[`--inspect-brk` option](https://nodejs.org/en/docs/guides/debugging-getting-started/#command-line-options)
 in order for debuggers to connect to it (on the default port, 9229).
 
 > For example, use this launch configuration in **Visual Studio Code**:
@@ -100,7 +100,7 @@ in order for debuggers to connect to it (on the default port, 9229).
 >   "request": "launch",
 >   "name": "Launch via Yarn",
 >   "runtimeExecutable": "yarn",
->   "runtimeArgs": ["dev:debug"],
+>   "runtimeArgs": ["debug"],
 >   "port": 9229
 > }
 > ```
diff --git a/public/static/docs/user-guide/contributing/index.md b/public/static/docs/user-guide/contributing/index.md
deleted file mode 100644
index cb1f5bc1fb..0000000000
--- a/public/static/docs/user-guide/contributing/index.md
+++ /dev/null
@@ -1,35 +0,0 @@
-# Contributing
-
-## Contributing to DVC
-
-We welcome [contributions](/doc/user-guide/contributing/core) to
-[DVC](https://github.com/iterative/dvc) by the community.
-
-- [How to report a problem](/doc/user-guide/contributing/core#how-to-report-a-problem)
-
-- [Submitting changes](/doc/user-guide/contributing/core#submitting-changes)
-
-- [Development environment](/doc/user-guide/contributing/core#development-environment)
-
-- [Running tests](/doc/user-guide/contributing/core#running-tests)
-
-- [Testing remotes](/doc/user-guide/contributing/core#testing-remotes)
-
-- [Code style guidelines (for Python)](/doc/user-guide/contributing/core#code-style-guidelines-for-python)
-
-- [Commit message format guidelines](/doc/user-guide/contributing/core#commit-message-format-guidelines)
-
-## Contributing Docs
-
-We welcome any contributions to our documentation repository,
-[dvc.org](https://github.com/iterative/dvc.org). Contributions can be updates to
-the documentation content, or (rare) changes to the JS engine we use to run the
-website.
-
-- [Structure of the project](/doc/user-guide/contributing/docs#structure-of-the-project)
-
-- [Submitting changes](/doc/user-guide/contributing/docs#submitting-changes)
-
-- [Development environment](/doc/user-guide/contributing/docs#development-environment)
-
-- [Doc style guidelines and tips (for JavaScript and Markdown)](/doc/user-guide/contributing/docs#doc-style-guidelines-and-tips-for-java-script-and-markdown)
diff --git a/public/static/docs/user-guide/dvc-files-and-directories.md b/public/static/docs/user-guide/dvc-files-and-directories.md
index 272426ace6..e971e23df8 100644
--- a/public/static/docs/user-guide/dvc-files-and-directories.md
+++ b/public/static/docs/user-guide/dvc-files-and-directories.md
@@ -41,6 +41,12 @@ operation:
 
 - `.dvc/lock`: Lock file for the entire DVC project
 
+- `.dvc/tmp`: Directory for miscellaneous temporary files
+
+- `.dvc/tmp/rwlock`: JSON file that contains read and write locks for specific
+  dependencies and outputs, to allow safely running multiple DVC commands in
+  parallel.
+
 ## Structure of cache directory
 
 There are two ways in which the data is stored in <abbr>cache</abbr>: As a
diff --git a/public/static/docs/user-guide/large-dataset-optimization.md b/public/static/docs/user-guide/large-dataset-optimization.md
index 5c29ed0f09..b88a94a96f 100644
--- a/public/static/docs/user-guide/large-dataset-optimization.md
+++ b/public/static/docs/user-guide/large-dataset-optimization.md
@@ -38,11 +38,11 @@ Symbolic links, and Reflinks in more recent systems. While reflinks bring all
 the benefits and none of the worries, they're not commonly supported in most
 platforms yet. Hard/soft links optimize **speed** and **space** in the file
 system, but may break your workflow since updating hard/sym-linked files tracked
-by DVC in the workspace causes <abbr>cache</abbr> corruption. These 2 link types
-thus require using cache **protected mode** (see the `cache.protected` config
-option in `dvc config cache`). Finally, a 4th "linking" option is to actually
-copy files from/to the cache, which is safe but inefficient – especially for
-large files (several GBs or more).
+by DVC in the <abbr>workspace</abbr> causes <abbr>cache</abbr> corruption. These
+2 link types thus require using cache **protected mode** (see the
+`cache.protected` config option in `dvc config cache`). Finally, a 4th "linking"
+option is to actually copy files from/to the cache, which is safe but
+inefficient – especially for large files (several GBs or more).
 
 > Some versions of Windows (e.g. Windows Server 2012+ and Windows 10 Enterprise)
 > support hard or soft links on the
@@ -92,9 +92,9 @@ efficiency:
 
 4. **`copy`**: An inefficient "linking" strategy, yet supported on all file
    systems. Using `copy` means there will be no file links, but that the tracked
-   files will be duplicated as copies existing in both the cache and workspace.
-   Suitable for scenarios with relatively small data files, where copying them
-   is not a storage performance concern.
+   files will be duplicated as copies existing in both the cache and
+   <abbr>workspace</abbr>. Suitable for scenarios with relatively small data
+   files, where copying them is not a storage performance concern.
 
 > DVC avoids `symlink` and `hardlink` types by default to protect user from
 > accidental cache corruption. Refer to the
@@ -120,6 +120,10 @@ file link types. Please refer to the
 [Update a Tracked File](/doc/user-guide/updating-tracked-files) on how to manage
 tracked files under these cache configurations.
 
+To make sure that the data files in the workspace are consistent with the
+<abbr>project</abbr>'s `cache.type` option, you may use `dvc checkout --relink`.
+See `dvc checkout` for more information.
+
 ---
 
 > \***copy-on-write links or "reflinks"** are a relatively new way to link files
diff --git a/server.js b/server.js
index 8ac859e014..8f94111f0d 100644
--- a/server.js
+++ b/server.js
@@ -1,9 +1,13 @@
 /* eslint-env node */
 
-// This file doesn't go through babel or webpack transformation. Make sure the
-// syntax and sources this file requires are compatible with the current Node.js
-// version you are running. (See https://github.com/zeit/next.js/issues/1245 for
-// discussions on universal Webpack vs universal Babel.)
+/*
+ * Custom server (with custom routes) See
+ * https://nextjs.org/docs/advanced-features/custom-server
+ *
+ * NOTE: This file doesn't go through babel or webpack. Make sure the syntax and
+ * sources this file requires are compatible with the current node version you
+ * are running.
+ */
 
 const { createServer } = require('http')
 const next = require('next')
@@ -21,7 +25,7 @@ app.prepare().then(() => {
     const { pathname, query } = parsedUrl
 
     /*
-     * Special URL redirects.
+     * HTTP redirects
      * NOTE: The order of the redirects is important.
      */
     if (
@@ -107,22 +111,21 @@ app.prepare().then(() => {
       res.end()
     } else if (/^\/doc(\/.*)?$/.test(pathname)) {
       /*
-       * Special docs engine handler
+       * Docs Engine handler
        */
 
-      // Force 404 response for any inexistent /doc item.
+      // Force 404 response code for any inexistent /doc item.
       if (!getItemByPath(pathname)) {
         res.statusCode = 404
       }
 
-      // Fire up docs engine!
+      // Custom route for all docs
       app.render(req, res, '/doc', query)
     } else {
       // Regular Next.js handler
       handle(req, res, parsedUrl)
     }
   }).listen(port, err => {
-    // Invokes `createServer` server.
     if (err) throw err
     console.info(`> Ready on localhost:${port}`)
   })
diff --git a/src/Documentation/Markdown/Markdown.js b/src/Documentation/Markdown/Markdown.js
index 7a708cd1be..4f9619c6e2 100644
--- a/src/Documentation/Markdown/Markdown.js
+++ b/src/Documentation/Markdown/Markdown.js
@@ -156,9 +156,9 @@ export default class Markdown extends React.PureComponent {
   }
 
   isInsideCodeBlock = elem => {
-    for (; elem && elem !== document; elem = elem.parentNode) {
-      if (elem.tagName === 'PRE') return true
-      if (elem.tagName === 'ARTICLE') return false
+    for (let el = elem; el && el !== document; el = el.parentNode) {
+      if (el.tagName === 'PRE') return true
+      if (el.tagName === 'ARTICLE') return false
     }
     return false
   }
diff --git a/src/styles.js b/src/styles.js
index ef89ddebf8..d4500df152 100644
--- a/src/styles.js
+++ b/src/styles.js
@@ -8,25 +8,25 @@ export const global = `
     font-weight: 400;
     text-rendering: optimizeLegibility !important;
   }
-  
+
   @-moz-document url-prefix() {
     body {
       font-weight: lighter !important;
     }
   }
-  
+
   body {
     padding: 0px;
     font-family: BrandonGrotesque, Tahoma, Arial;
     font-weight: normal;
     -webkit-font-smoothing: antialiased;
     line-height: 1.5;
-    
+
     // IE flex min-height fix https://stackoverflow.com/a/40491316
     display: flex;
     flex-direction: column;
   }
-  
+
   *:focus {
     outline: 0;
   }
@@ -51,13 +51,14 @@ export const sizes = {
 
 sizes.phablet = Math.floor((sizes.tablet + sizes.phone) / 2)
 
-export const media = Object.keys(sizes).reduce((accumulator, label) => {
-  accumulator[label] = (...args) => css`
-    @media (max-width: ${sizes[label]}px) {
-      ${css(...args)};
-    }
-  `
-  return accumulator
+export const media = Object.keys(sizes).reduce((acc, s) => {
+  return Object.assign(acc, {
+    [s]: (...args) => css`
+      @media (max-width: ${sizes[s]}px) {
+        ${css(...args)};
+      }
+    `
+  })
 }, {})
 
 export const container = css`
diff --git a/src/utils/sidebar.js b/src/utils/sidebar.js
index 1f2fb16a6d..0135d87975 100644
--- a/src/utils/sidebar.js
+++ b/src/utils/sidebar.js
@@ -1,11 +1,7 @@
 /* eslint-env node */
-
-const startCase = require('lodash.startcase')
-const sidebar = require('../../public/static/docs/sidebar.json')
-
 /*
-  We will use this helper to normalize sidebar structure and create
-  all of the resurces we need to prevent future recalculations.
+  These helpers normalize sidebar structure and create all the resources needed.
+  This prevents future recalculations.
 
   Target structure example:
 
@@ -22,11 +18,26 @@ const sidebar = require('../../public/static/docs/sidebar.json')
   }
 */
 
+const startCase = require('lodash.startcase')
+const sidebar = require('../../public/static/docs/sidebar.json')
+
 const PATH_ROOT = '/doc/'
 const FILE_ROOT = '/static/docs/'
 const FILE_EXTENSION = '.md'
 
-// Inner helpers
+function validateRawItem({ slug, source, children }) {
+  const isSourceDisabled = source === false
+
+  if (!slug) {
+    throw Error("'slug' field is required in objects in sidebar.json")
+  }
+
+  if (isSourceDisabled && (!children || !children.length)) {
+    throw Error(
+      "If you set 'source' to false, you had to add at least one child"
+    )
+  }
+}
 
 function findItem(data, targetPath) {
   if (data.length) {
@@ -45,42 +56,22 @@ function findItem(data, targetPath) {
   }
 }
 
-function findChildWithSource(item) {
-  return item.source ? item : findChildWithSource(item.children[0])
-}
-
 function findPrevItemWithSource(data, item) {
-  if (item.source) {
+  if (item && item.source) {
     return item
-  } else if (item.prev) {
+  } else if (item && item.prev) {
     const prevItem = findItem(data, item.prev)
 
     return findPrevItemWithSource(data, prevItem)
   }
 }
 
-function validateRawItem({ slug, source, children }) {
-  const isSourceDisabled = source === false
-
-  if (!slug) {
-    throw Error("'slug' field is required in objects in sidebar.json")
-  }
+function normalizeItem({ rawItem, parentPath, resultRef, prevRef }) {
+  validateRawItem(rawItem)
 
-  if (isSourceDisabled && (!children || !children.length)) {
-    throw Error(
-      "If you set 'source' to false, you had to add at least one child"
-    )
-  }
-}
+  const { label, slug, source, tutorials } = rawItem
 
-// Normalization
-
-function normalizeItem({ item, parentPath, resultRef, prevRef }) {
-  validateRawItem(item)
-
-  const { label, slug, source, tutorials } = item
-
-  // If prev item doesn't have source we need to recirsively search for it
+  // If prev item doesn't have source we need to search for it
   const prevItemWithSource =
     prevRef && findPrevItemWithSource(resultRef, prevRef)
 
@@ -111,9 +102,9 @@ function normalizeSidebar({
 
   data.forEach(rawItem => {
     const isShortcut = typeof rawItem === 'string'
-    const item = isShortcut ? { slug: rawItem } : rawItem
+    rawItem = isShortcut ? { slug: rawItem } : rawItem
     const normalizedItem = normalizeItem({
-      item,
+      rawItem,
       parentPath,
       resultRef,
       prevRef
@@ -123,10 +114,10 @@ function normalizeSidebar({
       prevRef.next = normalizedItem.path
     }
 
-    if (item.children) {
+    if (rawItem.children) {
       normalizedItem.children = normalizeSidebar({
-        data: item.children,
-        parentPath: `${parentPath}${item.slug}/`,
+        data: rawItem.children,
+        parentPath: `${parentPath}${rawItem.slug}/`,
         parentResultRef: resultRef,
         startingPrevRef: normalizedItem
       })
@@ -142,13 +133,19 @@ function normalizeSidebar({
   return currentResult
 }
 
+function findChildWithSource(item) {
+  return item.source ? item : findChildWithSource(item.children[0])
+}
+
+/*
+ * Exports
+ */
+
 const normalizedSidebar = normalizeSidebar({
   data: sidebar,
   parentPath: ''
 })
 
-// Exports
-
 function getItemByPath(path) {
   const normalizedPath = path.replace(/\/$/, '')
   const isRoot = normalizedPath === PATH_ROOT.slice(0, -1)
@@ -156,7 +153,9 @@ function getItemByPath(path) {
     ? normalizedSidebar[0]
     : findItem(normalizedSidebar, normalizedPath)
 
-  return item && findChildWithSource(item)
+  if (!item) return false
+
+  return findChildWithSource(item)
 }
 
 function getParentsListFromPath(path) {
diff --git a/src/utils/sidebar.test.js b/src/utils/sidebar.test.js
index e66f692f31..c8f977de3e 100644
--- a/src/utils/sidebar.test.js
+++ b/src/utils/sidebar.test.js
@@ -336,20 +336,31 @@ describe('SidebarMenu/helper', () => {
       expect(getItemByPath('/doc')).toEqual(result)
     })
 
-    it('Returns first child with source for sourceless parents', () => {
+    // eslint-disable-next-line max-len
+    it('Returns first child with source for all parents with source:false', () => {
       const rawData = [
         {
-          slug: 'item-name',
+          slug: 'item',
           source: false,
           children: [
-            { slug: 'nested-item', source: false, children: ['subnested-item'] }
+            {
+              slug: 'nested',
+              source: false,
+              children: [
+                {
+                  slug: 'subnested',
+                  source: false,
+                  children: ['leaf-item']
+                }
+              ]
+            }
           ]
         }
       ]
       const result = {
-        label: 'Subnested Item',
-        path: '/doc/item-name/nested-item/subnested-item',
-        source: '/static/docs/item-name/nested-item/subnested-item.md',
+        label: 'Leaf Item',
+        path: '/doc/item/nested/subnested/leaf-item',
+        source: '/static/docs/item/nested/subnested/leaf-item.md',
         tutorials: {},
         prev: undefined,
         next: undefined
@@ -358,7 +369,9 @@ describe('SidebarMenu/helper', () => {
       jest.doMock('../../public/static/docs/sidebar.json', () => rawData)
       const { getItemByPath } = require('./sidebar')
 
-      expect(getItemByPath('/doc/item-name')).toEqual(result)
+      expect(getItemByPath('/doc/item')).toEqual(result)
+      expect(getItemByPath('/doc/item/nested')).toEqual(result)
+      expect(getItemByPath('/doc/item/nested/subnested')).toEqual(result)
     })
   })