title: NPM install Error: self signed certificate in certificate chain
body: <p>At my company, there is an auto signed ssl certificate. So they're some npm packages that cannot be installed because of it.</p>
  
  <p>I already add <code>strict-ssl=false</code> in <code>.npmrc</code> or <code>--strict-ssl=false</code> command args.</p>
  
  <p>It works for some packages but some doesn't seems to take in charge this option.</p>
  
  <p>For exemple, I tried to install <em>Cypress</em> : </p>
  
  <p><strong>Command :</strong></p>
  
  <p><code>npm i cypress --save-dev --strict-ssl=false
  </code></p>
  
  <p><strong>Error logs :</strong></p>
  
  <pre><code>&gt; cypress@3.4.0 postinstall /Users/mchoraine/Documents/Workplace/SAMSE/rechercheproduit/rechercheproduit-front/node_modules/cypress
  &gt; node index.js --exec install
  
  Installing Cypress (version: 3.4.0)
  
   ✖  Downloading Cypress    
     → Cypress Version: 3.4.0
      Unzipping Cypress      
      Finishing Installation 
  The Cypress App could not be downloaded.
  
  Please check network connectivity and try again:
  
  ----------
  
  URL: https://download.cypress.io/desktop/3.4.0?platform=darwin&amp;arch=x64
  Error: self signed certificate in certificate chain
  
  ----------
  
  Platform: darwin (18.6.0)
  Cypress Version: 3.4.0
  </code></pre>
  
  <p>Problem seems to occur only for packages with <code>postinstall</code></p>
  
  <p>The smartest things would be to change the SSL certificate but unfortunately it can't be done.</p>
  
  <p>So are you aware of an alternative to bypass certificat verification on npm postinstall ?</p>
  
  <p>Thanks in advance for your proposal. </p>