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href="../../cli-commands/npm-org">npm org<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Manage orgs</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-outdated">npm outdated<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Check for outdated packages</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-owner">npm owner<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Manage package owners</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-pack">npm pack<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Create a tarball from a package</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-ping">npm ping<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Ping npm registry</span></a></div><div 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class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Rebuild a package</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-repo">npm repo<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Open package repository page in the browser</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-restart">npm restart<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Restart a package</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-root">npm root<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Display npm root</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-run-script">npm run-script<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Run arbitrary package scripts</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-search">npm search<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Search for packages</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-shrinkwrap">npm shrinkwrap<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Lock down dependency versions for publication</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-star">npm star<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Mark your favorite packages</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-stars">npm stars<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">View packages marked as favorites</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-start">npm start<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Start a package</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-stop">npm stop<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Stop a package</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-team">npm team<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Manage organization teams and team memberships</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-test">npm test<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Test a package</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-token">npm token<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Manage your authentication tokens</span></a></div><div class="css-l3rx45"><a 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bNiGAM">View registry info</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../cli-commands/npm-whoami">npm whoami<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Display npm username</span></a></div></div></div><div><button class="Accordion__SectionButton-i8yhwx-0 dsecBh">configuring-npm</button><div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../configuring-npm/folders">folders<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Folder Structures Used by npm</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../configuring-npm/install">install<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Download and install node and npm</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../configuring-npm/npmrc">npmrc<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">The npm config files</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../configuring-npm/package-lock-json">package-lock.json<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">A manifestation of the manifest</span></a></div><div class="css-l3rx45"><a aria-current="page" class="links__SidebarLink-sc-19vgq0o-3 iPgskl active-sidebar-link" href="../../configuring-npm/package-locks">package-locks<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">An explanation of npm lockfiles</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../configuring-npm/package-json">package.json<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Specifics of npm&#x27;s package.json handling</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../configuring-npm/shrinkwrap-json">shrinkwrap.json<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">A publishable lockfile</span></a></div></div></div><div><button class="Accordion__SectionButton-i8yhwx-0 dsecBh">using-npm</button><div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../using-npm/config">config<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">More than you probably want to know about npm configuration</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../using-npm/developers">developers<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Developer Guide</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../using-npm/disputes">disputes<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Handling Module Name Disputes</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../using-npm/orgs">orgs<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Working with Teams &amp; Orgs</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../using-npm/registry">registry<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">The JavaScript Package Registry</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../using-npm/removal">removal<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Cleaning the Slate</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../using-npm/scope">scope<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">Scoped packages</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../using-npm/scripts">scripts<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">How npm handles the &quot;scripts&quot; field</span></a></div><div class="css-l3rx45"><a class="links__SidebarLink-sc-19vgq0o-3 iPgskl" href="../../using-npm/semver">semver<span class="DocLinks__LinkDesc-sc-1vrw6od-0 bNiGAM">The semantic versioner for npm</span></a></div></div></div></nav><style data-emotion-css="16vu25q">.css-16vu25q{box-sizing:border-box;margin:0;min-width:0;width:100%;}</style><div class="css-16vu25q"><div class="Page__Content-sc-4b62ym-0 gJQTGP documentation"><div><h1 id="package-locks5" style="position:relative;"><a href="#package-locks5" aria-label="package locks5 permalink" class="header-link-class before"><svg aria-hidden="true" height="20" version="1.1" viewBox="0 0 16 16" width="20"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>package-locks</h1>
<h2 id="an-explanation-of-npm-lockfiles" style="position:relative;"><a href="#an-explanation-of-npm-lockfiles" aria-label="an explanation of npm lockfiles permalink" class="header-link-class before"><svg aria-hidden="true" height="20" version="1.1" viewBox="0 0 16 16" width="20"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>An explanation of npm lockfiles</h2>
<h3 id="description" style="position:relative;"><a href="#description" aria-label="description permalink" class="header-link-class before"><svg aria-hidden="true" height="20" version="1.1" viewBox="0 0 16 16" width="20"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Description</h3>
<p>Conceptually, the "input" to <a href="../../cli-commands/npm-install"><code class="language-text">npm install</code></a> is a <a href="../../configuring-npm/package-json">package.json</a>, while its
"output" is a fully-formed <code class="language-text">node_modules</code> tree: a representation of the
dependencies you declared. In an ideal world, npm would work like a pure
function: the same <code class="language-text">package.json</code> should produce the exact same <code class="language-text">node_modules</code>
tree, any time. In some cases, this is indeed true. But in many others, npm is
unable to do this. There are multiple reasons for this:</p>
<ul>
<li>different versions of npm (or other package managers) may have been used to install a package, each using slightly different installation algorithms.</li>
<li>a new version of a direct semver-range package may have been published since the last time your packages were installed, and thus a newer version will be used.</li>
<li>A dependency of one of your dependencies may have published a new version, which will update even if you used pinned dependency specifiers (<code class="language-text">1.2.3</code> instead of <code class="language-text">^1.2.3</code>)</li>
<li>The registry you installed from is no longer available, or allows mutation of versions (unlike the primary npm registry), and a different version of a package exists under the same version number now.</li>
</ul>
<p>As an example, consider package A:</p>
<div class="gatsby-highlight" data-language="json"><pre class="language-json"><code class="language-json"><span class="token punctuation">{</span>
  <span class="token property">"name"</span><span class="token operator">:</span> <span class="token string">"A"</span><span class="token punctuation">,</span>
  <span class="token property">"version"</span><span class="token operator">:</span> <span class="token string">"0.1.0"</span><span class="token punctuation">,</span>
  <span class="token property">"dependencies"</span><span class="token operator">:</span> <span class="token punctuation">{</span>
    <span class="token property">"B"</span><span class="token operator">:</span> <span class="token string">"&lt;0.1.0"</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span></code></pre></div>
<p>package B:</p>
<div class="gatsby-highlight" data-language="json"><pre class="language-json"><code class="language-json"><span class="token punctuation">{</span>
  <span class="token property">"name"</span><span class="token operator">:</span> <span class="token string">"B"</span><span class="token punctuation">,</span>
  <span class="token property">"version"</span><span class="token operator">:</span> <span class="token string">"0.0.1"</span><span class="token punctuation">,</span>
  <span class="token property">"dependencies"</span><span class="token operator">:</span> <span class="token punctuation">{</span>
    <span class="token property">"C"</span><span class="token operator">:</span> <span class="token string">"&lt;0.1.0"</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span></code></pre></div>
<p>and package C:</p>
<div class="gatsby-highlight" data-language="json"><pre class="language-json"><code class="language-json"><span class="token punctuation">{</span>
  <span class="token property">"name"</span><span class="token operator">:</span> <span class="token string">"C"</span><span class="token punctuation">,</span>
  <span class="token property">"version"</span><span class="token operator">:</span> <span class="token string">"0.0.1"</span>
<span class="token punctuation">}</span></code></pre></div>
<p>If these are the only versions of A, B, and C available in the
registry, then a normal <code class="language-text">npm install A</code> will install:</p>
<div class="gatsby-highlight" data-language="json"><pre class="language-json"><code class="language-json">A@<span class="token number">0.1</span>.<span class="token number">0</span>
`-- B@<span class="token number">0.0</span>.<span class="token number">1</span>
    `-- C@<span class="token number">0.0</span>.<span class="token number">1</span></code></pre></div>
<p>However, if B@0.0.2 is published, then a fresh <code class="language-text">npm install A</code> will
install:</p>
<div class="gatsby-highlight" data-language="bash"><pre class="language-bash"><code class="language-bash">A@0.1.0
<span class="token variable"><span class="token variable">`</span>-- B@0.0.2
    <span class="token variable">`</span></span>-- C@0.0.1</code></pre></div>
<p>assuming the new version did not modify B's dependencies. Of course,
the new version of B could include a new version of C and any number
of new dependencies. If such changes are undesirable, the author of A
could specify a dependency on B@0.0.1. However, if A's author and B's
author are not the same person, there's no way for A's author to say
that he or she does not want to pull in newly published versions of C
when B hasn't changed at all.</p>
<p>To prevent this potential issue, npm uses <a href="../../configuring-npm/package-lock-json">package-lock.json</a> or, if present, <a href="../../configuring-npm/shrinkwrap-json">npm-shrinkwrap.json</a>. These files are called package locks, or lockfiles.</p>
<p>Whenever you run <code class="language-text">npm install</code>, npm generates or updates your package lock,
which will look something like this:</p>
<div class="gatsby-highlight" data-language="json"><pre class="language-json"><code class="language-json"><span class="token punctuation">{</span>
  <span class="token property">"name"</span><span class="token operator">:</span> <span class="token string">"A"</span><span class="token punctuation">,</span>
  <span class="token property">"version"</span><span class="token operator">:</span> <span class="token string">"0.1.0"</span><span class="token punctuation">,</span>
  ...metadata fields...
  <span class="token property">"dependencies"</span><span class="token operator">:</span> <span class="token punctuation">{</span>
    <span class="token property">"B"</span><span class="token operator">:</span> <span class="token punctuation">{</span>
      <span class="token property">"version"</span><span class="token operator">:</span> <span class="token string">"0.0.1"</span><span class="token punctuation">,</span>
      <span class="token property">"resolved"</span><span class="token operator">:</span> <span class="token string">"https://registry.npmjs.org/B/-/B-0.0.1.tgz"</span><span class="token punctuation">,</span>
      <span class="token property">"integrity"</span><span class="token operator">:</span> <span class="token string">"sha512-DeAdb33F+"</span>
      <span class="token property">"dependencies"</span><span class="token operator">:</span> <span class="token punctuation">{</span>
        <span class="token property">"C"</span><span class="token operator">:</span> <span class="token punctuation">{</span>
          <span class="token property">"version"</span><span class="token operator">:</span> <span class="token string">"git://github.com/org/C.git#5c380ae319fc4efe9e7f2d9c78b0faa588fd99b4"</span>
        <span class="token punctuation">}</span>
      <span class="token punctuation">}</span>
    <span class="token punctuation">}</span>
  <span class="token punctuation">}</span>
<span class="token punctuation">}</span></code></pre></div>
<p>This file describes an <em>exact</em>, and more importantly <em>reproducible</em>
<code class="language-text">node_modules</code> tree. Once it's present, any future installation will base its
work off this file, instead of recalculating dependency versions off
<a href="../../configuring-npm/package-json">package.json</a>.</p>
<p>The presence of a package lock changes the installation behavior such that:</p>
<ol>
<li>The module tree described by the package lock is reproduced. This means
reproducing the structure described in the file, using the specific files
referenced in "resolved" if available, falling back to normal package resolution
using "version" if one isn't.</li>
<li>The tree is walked and any missing dependencies are installed in the usual
fashion.</li>
</ol>
<p>If <code class="language-text">preshrinkwrap</code>, <code class="language-text">shrinkwrap</code> or <code class="language-text">postshrinkwrap</code> are in the <code class="language-text">scripts</code>
property of the <code class="language-text">package.json</code>, they will be executed in order. <code class="language-text">preshrinkwrap</code>
and <code class="language-text">shrinkwrap</code> are executed before the shrinkwrap, <code class="language-text">postshrinkwrap</code> is
executed afterwards. These scripts run for both <code class="language-text">package-lock.json</code> and
<code class="language-text">npm-shrinkwrap.json</code>. For example to run some postprocessing on the generated
file:</p>
<div class="gatsby-highlight" data-language="json"><pre class="language-json"><code class="language-json">  <span class="token property">"scripts"</span><span class="token operator">:</span> <span class="token punctuation">{</span>
    <span class="token property">"postshrinkwrap"</span><span class="token operator">:</span> <span class="token string">"json -I -e \"this.myMetadata = $MY_APP_METADATA\""</span>
  <span class="token punctuation">}</span></code></pre></div>
<h4 id="using-locked-packages" style="position:relative;"><a href="#using-locked-packages" aria-label="using locked packages permalink" class="header-link-class before"><svg aria-hidden="true" height="20" version="1.1" viewBox="0 0 16 16" width="20"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Using locked packages</h4>
<p>Using a locked package is no different than using any package without a package
lock: any commands that update <code class="language-text">node_modules</code> and/or <code class="language-text">package.json</code>'s
dependencies will automatically sync the existing lockfile. This includes <code class="language-text">npm
install</code>, <code class="language-text">npm rm</code>, <code class="language-text">npm update</code>, etc. To prevent this update from happening,
you can use the <code class="language-text">--no-save</code> option to prevent saving altogether, or
<code class="language-text">--no-shrinkwrap</code> to allow <code class="language-text">package.json</code> to be updated while leaving
<code class="language-text">package-lock.json</code> or <code class="language-text">npm-shrinkwrap.json</code> intact.</p>
<p>It is highly recommended you commit the generated package lock to source
control: this will allow anyone else on your team, your deployments, your
CI/continuous integration, and anyone else who runs <code class="language-text">npm install</code> in your
package source to get the exact same dependency tree that you were developing
on. Additionally, the diffs from these changes are human-readable and will
inform you of any changes npm has made to your <code class="language-text">node_modules</code>, so you can notice
if any transitive dependencies were updated, hoisted, etc.</p>
<h4 id="resolving-lockfile-conflicts" style="position:relative;"><a href="#resolving-lockfile-conflicts" aria-label="resolving lockfile conflicts permalink" class="header-link-class before"><svg aria-hidden="true" height="20" version="1.1" viewBox="0 0 16 16" width="20"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>Resolving lockfile conflicts</h4>
<p>Occasionally, two separate npm install will create package locks that cause
merge conflicts in source control systems. As of <code class="language-text">npm@5.7.0</code>, these conflicts
can be resolved by manually fixing any <code class="language-text">package.json</code> conflicts, and then
running <code class="language-text">npm install [--package-lock-only]</code> again. npm will automatically
resolve any conflicts for you and write a merged package lock that includes all
the dependencies from both branches in a reasonable tree. If
<code class="language-text">--package-lock-only</code> is provided, it will do this without also modifying your
local <code class="language-text">node_modules/</code>.</p>
<p>To make this process seamless on git, consider installing
<a href="https://npm.im/npm-merge-driver"><code class="language-text">npm-merge-driver</code></a>, which will teach git how
to do this itself without any user interaction. In short: <code class="language-text">$ npx
npm-merge-driver install -g</code> will let you do this, and even works with
pre-<code class="language-text">npm@5.7.0</code> versions of npm 5, albeit a bit more noisily. Note that if
<code class="language-text">package.json</code> itself conflicts, you will have to resolve that by hand and run
<code class="language-text">npm install</code> manually, even with the merge driver.</p>
<h3 id="see-also" style="position:relative;"><a href="#see-also" aria-label="see also permalink" class="header-link-class before"><svg aria-hidden="true" height="20" version="1.1" viewBox="0 0 16 16" width="20"><path fill-rule="evenodd" d="M4 9h1v1H4c-1.5 0-3-1.69-3-3.5S2.55 3 4 3h4c1.45 0 3 1.69 3 3.5 0 1.41-.91 2.72-2 3.25V8.59c.58-.45 1-1.27 1-2.09C10 5.22 8.98 4 8 4H4c-.98 0-2 1.22-2 2.5S3 9 4 9zm9-3h-1v1h1c1 0 2 1.22 2 2.5S13.98 12 13 12H9c-.98 0-2-1.22-2-2.5 0-.83.42-1.64 1-2.09V6.25c-1.09.53-2 1.84-2 3.25C6 11.31 7.55 13 9 13h4c1.45 0 3-1.69 3-3.5S14.5 6 13 6z"></path></svg></a>See Also</h3>
<ul>
<li><a href="https://medium.com/@sdboyer/so-you-want-to-write-a-package-manager-4ae9c17d9527">https://medium.com/@sdboyer/so-you-want-to-write-a-package-manager-4ae9c17d9527</a></li>
<li><a href="../../configuring-npm/package-json">package.json</a></li>
<li><a href="../../configuring-npm/package-lock-json">package-lock.json</a></li>
<li><a href="../../configuring-npm/shrinkwrap-json">shrinkwrap.json</a></li>
<li><a href="../../cli-commands/npm-shrinkwrap">npm shrinkwrap</a></li>
</ul></div><div class="FoundTypo__Container-sc-1e373sc-0 fMOzaj"><p><span role="img" aria-label="eyes-emoji">👀</span> Found a typo? <a href="https://github.com/npm/cli/">Let us know!</a></p><p>The current stable version of npm is <a href="https://github.com/npm/cli/">here</a>. To upgrade, run: <code class="language-text">npm install npm@latest -g</code></p><p>To report bugs or submit feature requests for the docs, please post <a href="https://github.com/npm/cli/issues">here</a>. Submit npm issues <a href="https://github.com/npm/cli/issues">here.</a></p></div><script>
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