Web + SaaS + Full-Stack

Senior Freelance Web Developer serving Alicante, Costa Blanca, and Global Remote Clients

Marc Donaldson — 30+ Years Experience in Bespoke Software

Specializing in high-performance Next.js applications, SaaS platforms, and custom CRM systems for real estate, auctions, and service-based businesses. I build scalable, data-driven web products and modernise legacy systems into fast, maintainable architecture.

CRM Systems •SaaS Platforms •Real Estate Tools •Auction Management Software
Available for remote work globally — based in Spain (CET)
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Philosophy

Architecture meets design

CraftingscalableWeb,SaaS,andSoftwaresolutionswithSvelte,Next.js,andReact.

With over three decades in the industry, I bridge the gap between complex technical architecture and intuitive user design. I specialize in building high-performance web applications, SaaS solutions, and modern software products that scale.

30+Years
100+Projects
15+Techs
Core Stack

Languages

PHPJavaC++PythonColdFusionC# .NETTypeScriptJavaScript

Frameworks

ReactNext.jsTailwind CSSSvelte

Infrastructure

MySQLPostgresCloudflareMobile Development
Built for scale with
Next.jsCloudflareTypeScript
Capabilities

Digital Offerings

Strategic technical solutions crafted to solve complex architectural challenges.

01

Real Estate Web Development

02

Custom SaaS & CRM Development

03

Auction Management Systems

04

Legacy Code Modernization

05

CRM Strategy & Implementation

06

Page Speed Optimization

01

Real Estate Web Development

Bespoke property CRMs and custom property portals for local real estate agencies. High-performance tools designed for the modern property market.

Process
Discuss Project
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Journey

Experience & Background

Three decades of shipping software across multiple technology generations.
2018 - 2025

Full Stack Developer

MPL Enterprises

Developing and maintaining complex full-stack web solutions.

2009 - 2025

I.T. Manager / Web Developer

Lumsden Auctions

Managed IT infrastructure and developed custom web applications for auction management.

2009 - 2011

Senior Web Developer

Coast Digital

Built high-performance websites and digital solutions for a variety of clients.

2014 - 2014

Freelance Developer

Centigrade

Provided specialized development services on a project basis.

Academic
1993 - 1994

BTEC First in Information Technology

East Devon College

1993 - 1994

BTEC in Computer Studies

East Devon College

Network
Full Professional Resume

Let's connect
on LinkedIn

Connect for architecture inquiries, consulting, or full-stack opportunities.

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Portfolio

Featured Projects

A curated selection of digital products and high-performance applications.
All Case Studies
01

Ben Cook Real Estate

Real Estate Ecosystem

Premium property platform with bespoke CRM for the Costa Blanca real estate market.

50% faster lead processing & higher organic search visibility
02

Lumsden Auctions

Auction Management System

Full-scale auction management system with live bidding and automated cataloging.

40% increase in auction turnover through automation
03

Worldle

Game

Popular geography-based guessing game inspired by Wordle.

2M+ daily active users at peak
04

Studio T Casa

Beauty Salon

A beauty salon located within a stunning finca in Dolores, Alicante.

99/100 Lighthouse score & 30% more online bookings
05

Teuteuf

WordPress Design / Development

Bespoke WordPress design and ecosystem development.

Perfect Core Web Vitals on an image-heavy portfolio
06

Statele

Game

Interactive US state-based geography guessing game.

500k+ monthly active users & high retention
Next Stage
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Client Results
Firstly all I can say is Marc delivered on what he promised. He built my Property website and CRM from scratch. This was all done in the time it would usually take a team to do. I would fully Recommend Marc if there were stars to click it would be 5 stars for sure. *****
B
Ben CookDirector · Ben Cook Real Estate
Insights

Technical Journal

Deep dives into modern web architecture, SaaS development, and high-performance software engineering.
Full Journal
Real Estate7 min

Why Real Estate Agencies Need Custom Software

The real estate market in Spain is unique. Generic tools often fail to handle local nuances. Discover why bespoke software is the key to agency efficiency and growth.

Read Article
Technical7 min

How I Design CRM Systems for Clients

A transparent look into my design and development process for custom CRM systems. How I turn complex business requirements into intuitive digital tools.

Read Article
Local SEO5 min

Freelance Web Developer in Costa Blanca: What I Offer

Serving Alicante, Torrevieja, and the wider Costa Blanca region. Discover the benefits of working with a senior developer who understands the local Spanish business landscape.

Read Article
SaaS8 min

Custom CRM vs SaaS CRM: What Businesses Should Choose

Exploring the critical differences between off-the-shelf SaaS CRM tools and bespoke, custom-built systems. When to stick with the subscription, and when to build your own.

Read Article

Building technical authority through consistent engineering insights.

Architecture Hub — Coming Soon
Connect

Let's build together

Currently accepting new projects for remote full-stack development and architecture.
Fastest routeBook a Free Scoping Call30 min · No obligationOr send detailsGet a Project EstimateReplies within 24h
Phone / WhatsApp+34 627 191 675
LocationSpain · Remote worldwide
Available — Responds in 24h
Message

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