A more privacy-friendly blog

Vincent Bernat

When I started this blog, I embraced some free services, like Disqus or Google Analytics. These services are quite invasive for users’ privacy. Over the years, I have tried to correct this to reach a point where I do not rely on any “privacy-hostile” services.


Google Analytics is an ubiquitous solution to get a powerful analytics solution for free. It’s also a great way to provide data about your visitors to Google—also for free. There are self-hosted solutions like Matomo—previously Piwik.

I opted for a simpler solution: no analytics. It also enables me to think that my blog attracts thousands of visitors every day.


Google Fonts is a very popular font library and hosting service, which relies on the generic Google Privacy Policy. The google-webfonts-helper service makes it easy to self-host any font from Google Fonts. Moreover, with help from pyftsubset, I include only the characters used in this blog. The font files are lighter and more complete: no problem spelling “Antonín Dvořák”.


  • Before: YouTube
  • After: self-hosted

Some articles are supported by a video (like “OPL2LPT: an AdLib sound card for the parallel port“). In the past, I was using YouTube, mostly because it was the only free platform with an option to disable ads. Streaming on-demand videos is usually deemed quite difficult. For example, if you just use the <video> tag, you may push a too big video for people with a slow connection. However, it is not that hard, thanks to hls.js, which enables to deliver video sliced in segments available at different bitrates. Users with Java­Script disabled are still delivered with a progressive version of medium quality.

In “Self-hosted videos with HLS”, I explain this approach in more details.


Disqus is a popular comment solution for static websites. They were recently acquired by Zeta Global, a marketing company and their business model is supported only by advertisements. On the technical side, Disqus also loads several hundred kilobytes of resources. Therefore, many websites load Disqus on demand. That’s what I did. This doesn’t solve the privacy problem and I had the sentiment people were less eager to leave a comment if they had to execute an additional action.

For some time, I thought about implementing my own comment system around Atom feeds. Each page would get its own feed of comments. A piece of Java­Script would turn these feeds into HTML and comments could still be read without Java­Script, thanks to the default rendering provided by browsers. People could also subscribe to these feeds: no need for mail notifications! The feeds would be served as static files and updated on new comments by a small piece of server-side code. Again, this could work without Javascript.

Day Planner by Fowl Language Comics
Fowl Language Comics: Day Planner or the real reason why I didn't code a new comment system.

I still think this is a great idea. But I didn’t feel like developing and maintaining a new comment system. There are several self-hosted alternatives, notably Isso and Commento. Isso is a bit more featureful, with notably an imperfect import from Disqus. Both are struggling with maintenance and are trying to become sustainable with a paid hosted version.1 Commento is more privacy-friendly as it doesn’t use cookies at all. However, cookies from Isso are not essential and can be filtered with nginx:

proxy_hide_header Set-Cookie;
proxy_hide_header X-Set-Cookie;
proxy_ignore_headers Set-Cookie;

In Isso, there is currently no mail notifications, but I have added an Atom feed for each comment thread.

Another option would have been to not provide comments anymore. However, I had some great contributions as comments in the past and I also think they can work as some kind of peer review for blog articles: they are a weak guarantee that the content is not totally wrong.

Search engine🔗

A way to provide a search engine for a personal blog is to provide a form for a public search engine, like Google. That’s what I did. I also slapped some Java­Script on top of that to make it look like not Google.

The solution here is easy: switch to DuckDuckGo, which lets you customize a bit the search experience:

<form id="lf-search" action="https://duckduckgo.com/">
  <input type="hidden" name="kf" value="-1">
  <input type="hidden" name="kaf" value="1">
  <input type="hidden" name="k1" value="-1">
  <input type="hidden" name="sites" value="vincent.bernat.im/en">
  <input type="submit" value="">
  <input type="text" name="q" value="" autocomplete="off" aria-label="Search">

The Java­Script part is also removed as DuckDuckGo doesn’t provide an API. As it is unlikely that more than three people will use the search engine in a year, this seems a good idea to not spend too much time on this non-essential feature.


  • Before: RSS feed
  • After: still RSS feed but also a MailChimp newsletter

Nowadays, RSS feeds are far less popular they were before. I am still baffled as why a technical audience wouldn’t use RSS, but some readers prefer to receive updates by mail.

MailChimp is a common solution to send newsletters. It provides a simple integration with RSS feeds to trigger a mail each time new items are added to the feed. From a privacy point of view, MailChimp seems a good citizen: data collection is mainly limited to the amount needed to operate the service. Privacy-conscious users can still avoid this service and use the RSS feed.

Less Java­Script🔗

  • Before: third-party Java­Script code
  • After: self-hosted Java­Script code

Many privacy-conscious people are disabling Java­Script or using extensions like uMatrix or NoScript. Except for comments, I was using Java­Script only for non-essential stuff:

For mathematical formulae, I have switched from MathJax to KaTeX. The later is faster but also enables server-side rendering: it produces the same output regardless of browser. Therefore, client-side Java­Script is not needed anymore.

For sidenotes, I have turned the Java­Script code doing the transformation into Python code, with pyquery. No more client-side Java­Script for this aspect either.

The remaining code is still here but is self-hosted.

Memento: CSP🔗

The HTTP Content-Security-Policy header controls the resources that a user agent is allowed to load for a given page. It is a safeguard and a memento for the external resources a site will use. Mine is moderately complex and shows what to expect from a privacy point of view:3

  default-src 'self' blob:;
  script-src  'self' blob: https://d1g3mdmxf8zbo9.cloudfront.net/js/;
  object-src  'self' https://d1g3mdmxf8zbo9.cloudfront.net/images/;
  img-src     'self' data: https://d1g3mdmxf8zbo9.cloudfront.net/images/;
  frame-src   https://d1g3mdmxf8zbo9.cloudfront.net/images/;
  style-src   'self' 'unsafe-inline' https://d1g3mdmxf8zbo9.cloudfront.net/css/;
  font-src    'self' about: data: https://d1g3mdmxf8zbo9.cloudfront.net/fonts/;
  worker-src  blob:;
  media-src   'self' blob: https://luffy-video.sos-ch-dk-2.exo.io;
  connect-src 'self' https://luffy-video.sos-ch-dk-2.exo.io https://comments.luffy.cx;
  frame-ancestors 'none';

I am quite happy having been able to reach this result. 😊

  1. For Isso, look at comment.sh. For Commento, look at commento.io↩︎

  2. You may have noticed I am a footnote sicko and use them all the time for pointless stuff. ↩︎

  3. I don’t have issue with using a CDN like CloudFront: it is a paid service and Amazon AWS is not in the business of tracking users. ↩︎

Share this article