What powers 
sel4.systems?
Last seen Oct 2026 · 16 technologies across 13 categories
Analytics
Caching
CDN
Font scripts
JavaScript graphics
JavaScript libraries
Miscellaneous
PaaS
Programming languages
Security
UI frameworks
Web servers
AI Crawlers
Doesn't mention any of the 33 AI crawlers we track in its robots.txt; all are allowed by default. Checked Nov 2026.
- robots.txt found
- llms.txt not found
- ai.txt not found
- Nov 2026 * removed from robots.txt
- Oct 2026 * added to robots.txt
- Oct 2026 * removed from robots.txt
- Oct 2026 * added to robots.txt
- Sep 2026 * removed from robots.txt
- Sep 2026 * added to robots.txt
Top search keywords
| Keyword | Position | Est. monthly visits |
|---|---|---|
| sel4 microkernel | #1 | 15 |
| sel4 kernel | #1 | 9 |
| microkernel os | #4 | 5 |
| os kernel | #51 | 3 |
| darpa provers | #9 | 1 |
| c coding style guide | #14 | 1 |
| stable kernel | #60 | 1 |
| l4 microkernel | #6 | 0 |
| fastest os | #13 | 0 |
| microkernel operating system | #14 | 0 |
| what is microkernel | #15 | 0 |
| c coding style | #18 | 0 |
| grounded motherboard | #20 | 0 |
| system kernel | #20 | 0 |
| operating kernel | #22 | 0 |
| security kernel | #22 | 0 |
| what is the most secure operating system | #22 | 0 |
| autoware-github | #23 | 0 |
| kernel source | #24 | 0 |
| secure kernel | #24 | 0 |
| kernel of a group | #29 | 0 |
| kry10 | #29 | 0 |
| coding standards for c language | #30 | 0 |
| os engineer | #31 | 0 |
| kernel of group | #33 | 0 |
The site's top keywords in Google (US), with the visits each one is estimated to bring per month.
Top backlinks
Top links pointing at the site, one per source domain, strongest first. The anchor text opens the page carrying the link.
AI Crawlers
No AI crawlers blocked
Audience
- 65% desktop
- 35% phone
United States
Where the site's Chrome visitors come from, largest estimated audience first.
Open Page Rank
6.26 / 10 · ranked #91,858 of all domains
230 referring domains · OpenPageRank
Search traffic
35 est. monthly organic visits (US)
48 keywords in Google's top 30
Core Web Vitals
| LCP | 2.3 s |
| INP | 50 ms |
| CLS | 0 |
| TTFB | 1300 ms |
Real user p75, Chrome UX Report, Sep 2026.
Page
- Language: English
- Weight: 5.4 MB · 45 requests
Homepage as crawled by the HTTP Archive, Oct 2026.
Infrastructure
- Registered Mar 2014 (12 years) via 1API GmbH, renews Mar 2027
- Hosted on MAMMOTHMEDIA-AS-AP - Mammoth Media Pty Ltd (103.230.158.80)
- DNS: zoneedit.com
- Email: sel4.systems
- Email security: SPF (hard fail), DMARC monitor only
- SSL: Let's Encrypt, ECDSA P256, expires Jan 2027
- Common Crawl link graph: rank 442,020, 6 hosts
- Verified with: Google, Yahoo
DNS records as swept Nov 2026, certificate as seen Nov 2026, registration from the registry's RDAP service. How the web is hosted
Subdomains
| Host | Techs |
|---|---|
| lists.sel4.systems | 8 |
| docs.sel4.systems | 6 |
| sel4.systems | 6 |
| beta.sel4.systems | 4 |