No account managers. No Monday standups. No Jira tickets.
No 90-day onboarding. No six-figure retainer. No corporate theatre. One developer. One stack. One focus: your product, shipped.
Sole tradersSide hustlesSmall businessesStartupsFunded ventures
Same build quality at every level. The only thing that changes is scope.
What we build
Build. Rescue. Advise.
Three tracks. One developer. All delivered at a pace that'll make your current agency nervous.
Build
Product Development
Websites, SaaS platforms, AI tools, client portals. Fixed scope. Fixed price. Live in weeks.
From £1.5k — websites from £500
Rescue
Takeover & Fix
Stuck with a broken build, a ghost developer, or an agency bleeding you dry? We take over, fix it, and hand it back working.
⚡ From £500 — scoped on inspection
Advise
Strategy & Architecture
Paid deep-dive on your idea — market fit, technical architecture, build plan, honest verdict. Walk away with a blueprint.
⚡ From £500 — delivered in 48hrs
Starting small? Even better.
A website for your dog walking business. A booking page for your PT sessions. A portfolio for your trades work. A landing page for your side hustle. Same build quality as a £20k platform — just faster and sharper.
No sales calls. No pitch decks. Five quick questions and we'll come back with a scope, a price, and a realistic timeline. Whether it's a £250 landing page or a £25k platform.
⚡ Quick brief
5 questions • 2 minutes
Step 1 — Project type
What are you looking to build?
SaaS Platform
Mobile App
Website / Landing Page
AI-Powered Tool
MVP / Prototype
Rescue a broken build
Strategy / Architecture advice
Something else
⚡ AI: Your selection shapes every question that follows. We only ask what's relevant.
Step 2 — Adapted to your selection
Who are the end users?
B2B — Businesses
B2C — Consumers
Internal team
Marketplace (both)
⚡ AI: Understanding your audience determines the stack, auth model, and pricing architecture we recommend.
Step 3 — Scope
Describe your idea in a few sentences.
⚡ AI: The more context you give here, the fewer follow-ups we need. Think problem → solution → outcome.
Step 4 — Timeline & Budget
What's your ideal timeline?
ASAP — days
Weeks
1–2 months
Flexible
⚡ AI: We scope to your timeline. Tighter deadlines = tighter MVPs. We'll tell you what's realistic.
Step 5 — Contact
Where do we send the response?
⚡ AI: If the idea has legs, you'll get a scope, timeline, and fixed price. If it's not a fit, we'll say so. No ghosting.
Brief received. We're on it.
You'll hear back with one of two things: a fixed-price scope document with a timeline, or honest feedback on why it's not a fit. No ghosting. No silence.
● Live builds — Active now
Currently building 3 products for clients.
Real-time visibility into what's on the bench. Project details classified — the work speaks for itself.
sierra21 — build monitor v2.1
$s21 status --all --live
// querying active builds...
→3 builds active|value: £250,000+|all systems green
→deployments this month:14| uptime: 99.9%
→next deployment:< 24hrs
Deploying
BUILD — 001
AI-powered SaaS command centre for the UK childcare sector. Multi-site ops, compliance, parent communications.
SaaS Platform72%
Next.jsSupabaseClaude AIVercelTailwind
In development
BUILD — 002
Vertical operations platform for trades and construction. Quoting, scheduling, compliance documentation.
SaaS Platform35%
Next.jsSupabasePostgreSQLVercel
Architecture
BUILD — 003
Client build. AI-integrated platform for a niche service sector. Details classified.
Client Build15%
ReactNode.jsAI/MLCloud
Combined active build value
£250,000+
Capability matrix
Full spectrum. Zero gaps.
Everything from architecture to deployment, handled by one person. No sub-contractors. No handoffs. No "let me check with the team".
Full-Stack Dev
Expert
AI Integration
Expert
UI / UX Design
Advanced
SEO & Analytics
Advanced
DevOps / Cloud
Expert
Market Research
Advanced
Global
English-speaking world
8
Companies built & sold
100%
Delivery rate
< 24h
Response time
Common questions
Straight answers. No fluff.
How much does a build cost?
It depends on scope. Micro builds (single pages, quick tools) from £250. Websites and MVPs from £500. Full SaaS platforms and complex builds from £5,000+. You'll get a fixed price upfront — no hourly billing, no scope creep invoices. Rescue jobs and advisory sessions are scoped on inspection.
How fast can you deliver?
Working demos in 5–7 days for most projects. Small builds and prototypes often ship in 48–72 hours. We move at a pace most agencies can't match because there's no committee, no layers, no sign-off chain.
What if I just have a rough idea?
That's fine — most clients do. Submit what you have through the smart form. If the idea has potential, we'll come back with a clear scope and architecture. If it needs refining, we'll tell you that too.
Do I own the code?
Yes. 100%. Every line of code, every design asset, every deployment config. It's your product. You get full access to the repository on completion.
What about support after launch?
You get full ownership of the code and deployment. We hand over with documentation so you or your team can maintain it. If something breaks down the line, that's what our Rescue service is for — we'll take a look, scope the fix, and get it sorted.
How do we communicate?
Email and async messaging. No Zoom calls, no weekly standups. You'll get regular progress updates and working previews you can test yourself. If we need something from you, we ask once and clearly.
The builder
James Williams. Ex-military. Eight companies built. One exit. Still building. I bring military-grade discipline to software — structured execution, zero waste, relentless forward momentum.
If you're a founder with conviction but no CTO, I'm your build partner. If your agency is bleeding you dry for basic changes, I'll fix that too. If you've got an idea but no clue where to start — that's exactly what I do, every day.
You'll probably never meet me — and that's exactly how it should be. This is about your software, not my face on a LinkedIn carousel.
Based in Asia-Pacific
Serves founders & SMBs globally
Async-first — timezone is never a barrier
Why I build
I've built eight businesses. Sold one. Started from nothing every time.
I know what it's like to have an idea and no budget. To compete against companies with ten times your headcount. To feel like the system isn't built for you.
It isn't. So I build tools for people who build anyway.
Founders. Sole traders. Small teams with big conviction. The ones who'd rather ship than pitch. Who measure success in revenue, not rounds raised.
I want your software to make you money — so you can spend your time on the things that actually matter. Family. Freedom. The life you started this for.
That's it. That's why Sierra21 exists.
14 deployments shipped this month · 99.9% uptime · all systems operational
Contact
Got an idea? Let's see if it has legs.
Submit your idea now and you'll get a straight answer — a scope, a price, and a realistic timeline. If it's not a fit, we'll tell you. No ghosting. No invoices for "discovery".