Companies Using Phusion Passenger

Phusion Passenger is the app server I'd least expect to find on a sports club's website, and yet that's where nearly a quarter of it is. A domain counts here when the Server or X-Powered-By header in our crawler's response names Passenger. In our October 2026 crawl that's 26,065 domains after cleaning, 14,325 matched to a company, 10th of 70 in Web Servers with 0.18%. On 13 October I requested a random sample of 60 by hand, plus all 50 rows of our company list, because a header tells you whose software built the response, not whose website it is.

What we took out, and why the chart is short

9 of my 60 sampled domains answered from OpenResty 1.21.4 with the same line, X-Powered-By: Phusion Passenger (mod_rails/mod_rack) 5.1.5. They're Chinese lottery sites on numeric domains, mostly without page titles, which is how they slipped past our title filter. We removed 2,884 of them, every domain showing both OpenResty and Alibaba Cloud's object storage. The chart has one point because the cleaned series starts in October. Since March 2026, 2,477 domains have dropped the header and 252 of those still show it on another hostname.

"Passenger hides behind Nginx or Apache on most sites. Of the 51 genuine sites in my sample, only eight put its name in the Server header. You find it in X-Powered-By, or you don't find it." - David Thomson, CTO at TechnologyChecker.io

Sales signal: any Passenger list undercounts, because the header can be switched off. Use it to find the Rails and Node.js shops that left it on, not to size Phusion's market.

Nearly a quarter is one sports platform

SportsEngine, the youth-sports platform, accounts for 6,108 domains, 23.43% of the clean set. Its club sites load SportsEngine's scripts, and all 11 in my sample reported Passenger without a version number from behind Cloudflare. Spectator Sports leads the industry chart at 13.08% for the same reason.

Sales signal: strip SportsEngine domains before prospecting. A club on SportsEngine didn't choose an app server, and SportsEngine is the only account behind all of them.

Vendors pick Passenger, customers inherit it

The company list makes the same point at the top end. Of our 50 rows, 36 are subdomains a software vendor runs. 21 are PeopleAdmin hiring portals, among them the University of Kentucky's, answering as Apache with Passenger 6.0.15. Seven are gift-card shops on Techsembly, for Mandarin Oriental, Aman, Raffles, Six Senses, Soho House, Banyan Group and COMO. Three are patient logins hosted on HealtheIntent, two are careers sites from Hospitality Online that report Passenger Enterprise 6.2.0, two are SimpleNexus mortgage portals and one is USA Hockey on SportsEngine. Ola, Munich Airport, Jazzercise, Furman University and the University of Hamburg's mathematics, informatics and natural sciences faculty run Passenger on their own servers.

"Most of the big names on this list never chose Passenger. PeopleAdmin, Techsembly and SportsEngine did, and their customers' subdomains carry the header." - David Thomson, CTO at TechnologyChecker.io

The overlap figures follow from how Passenger installs. 10,430 domains show it with Nginx today and 5,177 with Apache, out of 12,002 and 5,988 ever seen together. Passenger is a module inside those servers, so none of this is switching.

Sales signal: the account behind most enterprise rows is the vendor. PeopleAdmin, Techsembly and HealtheIntent are the buyers of hosting, monitoring and Passenger Enterprise support, not the universities and hotels.

The companies behind the domains

62.98% of matched companies with a known size have 1 to 10 employees and 85.82% have 50 or fewer; only 213 have more than 1,000 staff. 6.11% were founded before 1960, the universities and federations again. The United States has 5,159 matched companies, and the nine European countries in our top 15 add up to 3,902. EasyBroker, a Mexican real-estate CRM that builds agents' sites, loads on at least 671 domains, which helps explain both Mexico's 484 and Real Estate's 5.38%.

Sales signal: outside the platforms, the typical Passenger site is a small business whose developer or host set it up. Agencies and managed hosts are the route in, more than the business owner.

Rails, and a lot of Node.js

Across the 26,064 clean live domains, Ruby on Rails shows on 54.07%, a figure that's partly circular because our Rails rule also fires on a mod_rails or mod_rack header, which some Passenger builds send themselves. The Node.js side is larger than Passenger's Ruby reputation suggests: Next.js is on 13.13% and Express 4.84%. In my sample, Next.js and Express apps reported Passenger on Plesk servers that add PleskLin to the same header. Ahoy, a Rails analytics library, turns up on 0.79%.

Sales signal: a Next.js site answering through Passenger is usually on shared or panel-managed hosting. That's a prospect for a move to a managed Node platform.

Versions and what Enterprise costs

The open-source edition is free under the MIT licence on GitHub, where 6.2.0 came out on 18 August 2026. In the last 30 days we saw 3,625 Passenger domains already reporting 6.2.0 and 3,813 reporting 6.1.8. Older builds linger: counting only the most common version strings, at least 963 domains report a 5.x or 4.x release, and our list runs from PeopleAdmin's 6.0.15 to Munich Airport's Enterprise 5.0.29 and a 3.0.11 build on the University of Ferrara's directory. Passenger Enterprise is priced by server RAM, from $23.52 a month for production clusters on Phusion's pricing page.

Sales signal: a visible version string older than 6.0 is an upgrade or support conversation. Phusion's own Enterprise support is the obvious offer, and security scanners will find the same list useful.

Key takeaways

1. 26,065 domains, 10th of 70 in Web Servers with 0.18%, read from the Server or X-Powered-By header.

2. We removed 2,884 lottery sites that copy a Passenger 5.1.5 header behind OpenResty.

3. SportsEngine is 23.43% of the clean set, and 36 of our 50 company rows are subdomains that vendors such as PeopleAdmin run.

4. 62.98% of matched companies have 1 to 10 staff, and Node.js frameworks are common next to Rails.

5. Overlaps with Nginx and Apache are integration, not switching.

Working with the list

Remove SportsEngine domains first, then group the enterprise rows by the vendor behind the subdomain. For the full list of 26,065 Passenger domains with company and stack data, explore TechnologyChecker.io. Our guide to technology detection methods explains why a header detection can name the platform rather than the site owner.