WordPress (before)
sarahwestall.com
34
Perf 84
A11y 96
BP 92
SEO Custom-software studio
Hard problems,
Hard problems,
shipped fast.
We design custom solutions for clients who need more than a template. Ultimate speed. Post-quantum encryption. AI integration. Go-powered automation. We listen to the problem, then build exactly what fits it.
- 100Lighthouse score, every build
- Post-quantumcryptography in production
- Gofor the back-end-heavy lifting
Speed is king.
It helps dictate the rankings, along with SEO. With our systems, we get the max from both.
Sarah Westall site rebuild.
Same content, completely modernized — faster, more beautiful, more engaging, and with proper light and dark modes. WordPress on the left, our rebuild on the right.
Modernized rebuild (after)
dev.gnews.cz staging
99
Perf 100
A11y 100
BP 100
SEO The New York Times vs. NewsTosser.
nytimes.com versus a live NewsTosser destination site. Same Lighthouse run, same day.
nytimes.com
Google PageSpeed, May 2026
32
Perf 88
A11y 54
BP 92
SEO NewsTosser site
One of hundreds in the network
100
Perf 95
A11y 100
BP 100
SEO Hard problems, shipped in days, not months.
Post-quantum cryptography. End-to-end-encrypted messaging. Voting platforms. Real-time AI. These are the problems most shops politely decline — and the ones we've spent careers solving.
What's new is the pace. With AI woven directly into our build pipeline, the boring 80% writes itself: scaffolding, tests, docs, glue. Our senior engineers spend their hours on the 20% that actually matters. Work that used to take a quarter ships in a week — same hardened stack, same engineers shipping it, at a fraction of the cost. Custom software that used to be enterprise-only is suddenly within reach.
- 5×faster delivery
- Senior-builtAI-amplified, never AI-only
- Surprisinglyaffordable
Selected projects
All projects → Latest case study
GNews.cz
GNews, an Eight Language Beast< Perfect Speed, Perfect SEO.
- 8 languages
- 40K pre-rendered pages
- <250 ms TTFB
- 100 Lighthouse
- Zero trackers
- Self-hosted analytics
Keltus.io
This site is also a demo. The whole stack runs on a mini PC under a desk — and PageSpeed scores it 100/100/100/100.
Web
Sarah Westall
Complete rebuild of a 100K-monthly-viewer media site — WordPress out, Astro + Directus in.
cop.chat
Real-time discussion forum with E2E-encrypted DMs, anonymous posting, and pluggable AI.
Zavos International Dating
Cross-language dating platform with real-time AI translation across 16 languages and 32,000+ cities.
iOSAndroid
SecureVote
Ultra-secure election system with a remote Android voting app — designed for post-quantum migration.
Android
DisApp Messenger
Compliance-archived end-to-end encrypted messenger with escrow key recovery — no client-side backdoor.
Android
NewsTosser
AI news aggregation that rewrites unique articles for hundreds of destination sites.
Real people, reading this.
The team.
Meet everyone → Meet the team
John Devlin
Lead Project Manager
Boca Raton, Florida, USA
Twenty years in software development, product and engineering management, with a habit of shipping under impossible deadlines. John runs every Keltus engagement end-to-end.
Read full story → Pavel Kuznetsov Principal Backend Engineer Moscow, Russia
Nina Becker Frontend Lead Berlin, Germany
Tomáš Novák Principal Cryptographer Prague, Czech Republic
Yuki Nakamura Mobile Engineering Lead Tokyo, Japan
Eitan Cohen AI & Data Engineer Tel Aviv, Israel
Jelena Marković Head of Design & Conversion Belgrade, Serbia
Tuomas Korhonen Head of Infrastructure Helsinki, Finland
Got a hard problem?
Speed. Crypto. AI. CNC automation. Tell us what you need — we'll tell you what's actually possible.
Start a conversation →