Proposal: Nginx for Plausible Proxy + Security Filtering

[mroderick]

Problem

Plausible analytics (in application.html.haml) gets blocked by adblockers (6-60% of users).

Proposal

Run heroku/heroku-buildpack-nginx in front of Rails.

Benefits

1. Plausible proxy — map /js/script.js and /api/event through our domain, bypassing adblockers

Implementation

1. Add buildpack (index 1, before Ruby):

   heroku buildpacks:add --index 1 heroku-community/nginx
   

2. Create config/nginx.conf.erb with:

   • Plausible proxy routes (env var PLAUSIBLE_SCRIPT_URL)
   • Pass remaining traffic to Rails via UNIX socket
   • Security filters

3. Update Procfile:

   web: bin/start-nginx bundle exec puma
   

4. Update Plausible snippet in application.html.haml:

   <script async src="/js/script.js"></script>
   <script>
     window.plausible = window.plausible || function() { (plausible.q = plausible.q || []).push(arguments) }, plausible.init = plausible.init || function(i) { plausible.o = i || {} };
     plausible.init({ endpoint: "/api/event" })
   </script>

Secondary Benefits

With nginx in front of Rails, we gain additional controls:

• Filter unwanted traffic before it reaches the app
• Apply security headers easily
• Implement rate limiting
• Prevent buffer overflow attacks

References

• Heroku Nginx Buildpack
• Plausible Proxy Overview
• Plausible Proxy Guide: Nginx