2026
Communication platform / Multi-surface
RemoteLink
A focused remote support product designed around reliable communication, presence and low-friction collaboration.
Guillermo Madariaga Sierra
Electronics engineer · Full-stack developer
Systems · Architecture · 2026
Engineering systems that can evolve.
A visual portfolio of maintainable products, architecture and practical development supported by AI.
Backend developer · Speed Solutions · 7+ years · .NET · Web · Mobile · AI-enabled delivery
- 01BackgroundFrom physical systems to digital products.
- 02WorkBuilt across the stack.
- 03Work detailBuilt across the stack.
- 04More workMore selected work
- 05ApproachElegant is useful when it lasts.
- 06ArchitectureKeep the core independent. Let the edges adapt.
- 07StackBroad enough to connect the dots.
- 08PracticeFrom implementation to delivery.
- 09AI workflowTools should amplify judgment, not replace it.
- 10ContactLet’s build something that can be understood.
02
01 / Background
BACKGROUND / 01Full-stack developer · Electronics background
From physical systems to digital products.
Electronics trained me to trace signals, understand constraints and respect the whole system. Software became the medium for turning that way of thinking into products that can evolve.
For more than seven years I have worked across backend, web and mobile products. At Speed Solutions I contribute as a backend developer on two major production projects — billing, data management and various integrations.
I have maintained a .NET application for over four years, supporting its diagnosis, delivery and long-term evolution. I work cross-platform with Java, Python, SQL Server and local databases.
I stay current through self-directed learning of new tools and technologies.
ELECTRONICS → SOFTWARE
7+years building software
.NETbackend specialization
Web · Mobile · Desktopproduct surfaces
03
02 / Selected work
SELECTED WORK / 02Selected work
Built across the stack.
A small selection of systems and products where architecture, performance and the user experience have to work together.
04
03 / Selected work
SELECTED WORK / 02Selected work
Work detail
Different surfaces, same discipline: clear contracts, useful abstractions and careful delivery.
2026
Developer tooling / Windows
DevProxy Studio
A modular reverse proxy for exposing local applications to a LAN while capturing, persisting and inspecting HTTP traffic.
05
More work
ADDITIONAL WORK / 02More selected work
More work
Different surfaces, same discipline: clear contracts, useful abstractions and careful delivery.
2026
Mobile and device integration
RemotePad
A mobile control surface paired with a Windows service for remote input, screen capture and device-oriented workflows.
↳
A small selection of systems and products where architecture, performance and the user experience have to work together.
06
03 / Design principles
DESIGN PRINCIPLES / 03Development approach
Elegant is useful when it lasts.
I use architecture as a tool for change: enough structure to protect the important parts, never ceremony for its own sake.
Boundaries first
Clear domain boundaries keep products adaptable, testable and easier to reason about.
Performance by design
Fast experiences come from deliberate data flow, small client payloads and non-blocking work.
Useful complexity
Architecture earns its place when it protects change, not when it adds ceremony.
07
Architecture
ARCHITECTURE / 03A practical boundary map
FLOW ↓Keep the core independent. Let the edges adapt.
01
Presentation Web · API · desktop · mobile
02
Application Use cases · orchestration · contracts
03
Domain Rules · entities · events
04
Infrastructure Data · HTTP · messaging · adapters
The domain should not know whether it is being called by a browser, a mobile client or a background process. Ports express intent; adapters handle the outside world.
See the approach in a real project08
04 / Stack
STACK / 04Toolkit
Broad enough to connect the dots.
Specialized in .NET backend development, with experience across the surfaces and languages that make a product complete.
Backend
C# / .NET
ASP.NET Core
REST APIs
SignalR
SQL
Frontend
Astro
TypeScript
React
Responsive CSS
PWA
09
08 / Development practice
ENGINEERING / 04Toolkit
From implementation to delivery.
Specialized in .NET backend development, with experience across the surfaces and languages that make a product complete.
Mobile & desktop
Java
Kotlin
Flutter
.NET MAUI
Windows
Development practice
Clean Architecture
Hexagonal design
Git workflow
Azure & DevOps
Testing
Agile delivery
10
05 / AI workflow
AI WORKFLOW / 05AI
05 / AI workflow
Tools should amplify judgment, not replace it.
I work with AI agents, MCPs, skills and integrations across real projects — from requirements gathering to production deployment. My background includes neural networks and fuzzy systems from my degree, which gives me a practical understanding of how AI works beyond surface-level tooling. I use Claude Code, OpenCode and Codex in the terminal across WSL and Windows, supervising AI-assisted development directly in the IDE. The workflow covers unit testing, documentation, user manuals and production releases, always with human review and ownership of the result.
06 / Contact
Let’s build something that can be understood.
A product, system or technical challenge is a good place to start a conversation.
Start a conversation