Organic-Modern Software, Built for People

We design and deliver thoughtful software for businesses and homes—systems that feel warm, reliable, and quietly powerful. From cloud platforms to family apps and smart-home automations, our work blends craft with care.

London • England Trusted • Sustainable

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Our Story

“Citadel” is our promise: your data, your home, your business—kept safe. We build with empathy and iterate with you, turning complex ideas into calm, capable tools.

  • Discovery workshops & journey mapping
  • Accessible, inclusive design
  • Security first, privacy by default
  • Sustainable delivery, measurable outcomes

Services & Solutions

Illustrated eco-tiles that grow with your needs.

Web & Mobile Apps

Responsive, accessible, app-store ready. React, Native, and modern web stacks.

  • Design systems & UI kits
  • Offline-first experiences
  • App store publishing

Cloud Platforms

Scalable APIs, serverless, and data pipelines on AWS/Azure/GCP with strong observability.

  • Infrastructure as code
  • Automated testing
  • Zero-downtime deploys

Integrations & Automation

From CRMs to smart-home devices, we connect the dots and remove manual toil.

  • Workflow automation
  • Secure connectors
  • RPA where it fits

Domestic / Home Software

Family dashboards, care & safety apps, IoT orchestration with privacy built-in.

  • Home data hubs
  • Parental controls
  • Energy tracking

Data & AI Enablement

Search, summarise, detect and predict—with governance, not hype.

  • Responsible AI patterns
  • Analytics dashboards
  • ML pipelines

Support & Care Plans

Transparent SLAs, performance budgets, and regular improvement cycles.

  • Proactive monitoring
  • Incident response
  • Roadmap reviews

Industries Served

Branches that reach your domain.

Retail & eCom Healthcare Real Estate Fintech Public Sector Education Home & Lifestyle

Why Choose Citadel Key Systems

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Years building software
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Client satisfaction (%)
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Projects delivered
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Week MVP cycles

Secure by Design

OWASP practices, threat modelling, and privacy controls from day one.

Human-Centered

Research, prototyping, and continuous UX testing ensure adoption.

Measurable Outcomes

We define success metrics and ship improvements that move them.

Case Studies & Success Stories

Checkout experience on a laptop

Retail Replatform: 38% Higher Conversion

We rebuilt a legacy store into a composable commerce stack, adding real-time stock and 1-click checkout.

React • Headless
Healthcare dashboard on tablet

Care Dashboards for Clinics

Accessible patient portals with secure messaging and triage automations lowered wait times by 24%.

Accessibility AA
IoT devices

Smart-Home Hub

Unified control for lighting, energy, and safety—private by default and lightning fast.

IoT • Edge
Developers collaborating

Fintech API Modernisation

From monolith to microservices with observability; incidents down 70% within 3 months.

Cloud • SRE

Testimonials

Portrait of client

“They turned our backlog into a breathing product.” Weekly releases, zero drama.

—Retail Director

Portrait of client 2

“Security minded and kind.” They made our clinic portal genuinely accessible.

—Clinic Owner

Portrait of client 3

“Communication A+.” Clear budgets, clear outcomes, no surprises.

—Operations Lead

Insights & Resources

Paper and leaves

Domestic Software: Designing for Calm

Principles for useful, respectful apps in the home.

Read • 4 min
Cloud architecture sketch

Green Cloud Patterns

Lower latency, lower carbon—without compromising reliability.

Read • 6 min
Team collaboration

From Idea to MVP in 4 Weeks

Our discovery → prototype → validate loop.

Read • 5 min

Frequently Asked Questions

How soon can we start?

Discovery workshops can begin within two weeks. We then sequence design and engineering for a first release in ~4–6 weeks depending on scope.

Which technologies do you use?

Modern TypeScript/React, Node, Python, cloud-native stacks, and native mobile where appropriate—chosen to fit your team and scale.

Do you offer maintenance?

Yes. Care Plans include monitoring, backups, upgrades, security reviews, and quarterly roadmap sessions.

How do you price projects?

Transparent engagement models—see Pricing below.

Pricing & Engagement Models

Discovery Sprint

£3,500

1–2 weeks of research, workshops, and a clickable prototype.

  • Stakeholder interviews
  • User journeys & scope
  • Delivery plan & budget
Book Sprint

Fixed-Scope Build

From £18k

Well-defined outcomes with a clear timeline.

  • Milestone billing
  • Design + Engineering
  • UAT & training
Get Estimate

Dedicated Team

£8k / mo

Flexible capacity across design, engineering, and DevOps.

  • Monthly roadmap
  • Velocity reports
  • Continuous delivery
Reserve Capacity

Let’s build something meaningful

Tell us about your idea, and we’ll suggest the quickest, safest path to value.

Contact Details

Company: CITADEL KEY SYSTEMS LTD

Phone: 07537132605

Address:
399-405 Oxford Street
Office 7607GB, Unit 5, Area 1/1
London, England, W1C 2BU

Email: contact@citadelkeysystems.com

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