My philosophy
Every obstacle is a springboard to new possibilities. I tackle each challenge with passion and determination: true strength lies in the ability to adapt and innovate.
Available for development, security & training projects
Software · Web · AI · Training
From the idea to the finished product: software, websites and AI that are secure by design — and the training to make the most of them.
$ whoami cristian.ristagno $ cat profile.json { "role": "Senior Analyst Dev. IT Security", "team": "Purple (Red ⇄ Blue)", "stack": "C# · ASP.NET Core · T-SQL", "experience": "18+ years in IT", "mindset": "pilot-grade precision" } $ ▍
Companies I've worked with
Italia
Cumvincere
01 — About
Full-Stack IT professional with over 18 years of experience in the .NET ecosystem, specialising in innovative web and enterprise solutions. I integrate advanced cybersecurity and artificial intelligence to build systems that are secure, scalable and future-ready.
As a Purple Team member I connect red and blue teams so that every test becomes a better defense: I turn the results of controlled simulations into stronger detection, faster response and concrete mitigations — and having written the code, I know exactly where to make it stronger.
A purple team connects red and blue. What the tests reveal flows straight into stronger detections, faster response and continuously improving security controls — a unified approach instead of two teams working in silos.
Infrastructure efficiency · Value · Reliability · Experience & Competence

Every obstacle is a springboard to new possibilities. I tackle each challenge with passion and determination: true strength lies in the ability to adapt and innovate.
An enthusiastic team player who thrives in remote collaboration with talent around the world. Diverse perspectives and knowledge sharing are the pillars of collective success.
Driven by an insatiable ambition, I keep pursuing new challenges for professional growth. Every experience becomes a lesson on the way to the next goal.
I take on technology challenges proactively and with an innovative mindset, turning opportunities into tangible results and contributing to the evolution of the digital sector.
Aviation inspires me to push boundaries with curiosity and determination, and to turn ambition into concrete results.
02 — Services
Security testing
In-depth review of exposed web assets to find and fix weak entry points and misconfigurations across APIs, front-end and backend services.
Agreed, controlled simulations of multi-step scenarios to check that monitoring detects them and that response workflows work as expected.
Controlled tests for XSS, CSRF, IDOR, SQLi and logic flaws, to verify that the application and its detection mechanisms hold up.
Review of C# / ASP.NET applications from a developer's perspective: authentication, cryptography (AES, RSA, X.509), data access and secure SDLC integration.
Evaluation of session management through controlled tests to find token leakage, fixation and improper invalidation.
Clear, actionable reports that rank findings by real business risk and give developers concrete, testable fixes — not just a list of CVEs.
Software, web & digital
Custom business applications, secure from day one.
03 — Know-how evolution
Every phase added a new layer: from physical systems to the web, from enterprise data to real-time devices, all the way to security. Each layer is still there.
It started with physical systems: wiring, schematics and 3D design. That's where I learned that every component has a dependency, and that a single fault can stop the whole line. That's still how I think about systems.
Moving to the web, I learned to build sites and to understand how search engines and users find them. Leading projects taught me to balance code, clients and deadlines.
The .NET ecosystem became home. Logistics and business applications taught me data modeling, complex SQL and clean architecture: software that has to run every day, without surprises.
A step outside pure code, into quality control and operations. I learned to see software from the user's side and to verify, measure and question every step of a process. That's the auditor's eye.
Telemetry and GPS tracking: thousands of devices, data streams arriving in real time, live dashboards. Asynchronous communication, scale and resilience became everyday problems.
Everything comes together. Knowing how applications are built, I now focus on making them resilient: cryptography, web penetration testing and Purple Team practices, turning every test into better defenses.
A thirst for knowledge that never stops: new technologies, new threats, new teams to grow with.
Tools I work with
04 — Technical expertise
12 skills
8 skills
8 skills
8 skills
8 skills
8 skills
8 skills
12 skills
A holistic approach combining development expertise, security hardening and system architecture.
05 — Methodology
Domains, IPs and exposed services: a complete map of what needs protecting.
Live hosts, open ports and running services define the exposure.
Strengths and weaknesses across people, processes and technology.
Agreed, controlled scenarios based on your highest-risk threats.
Measure the real impact and check what detection and response actually catch.
Feedback cycles that strengthen detection, response and the code itself.
06 — Training
I believe true success is achieved together. I teach the way I learned: hands-on, with real cases, from someone who has written the code and then secured it.

07 — Beyond code
As an ATPL pilot I bring aviation discipline to security: pre-flight checks mirror assessments, in-flight monitoring mirrors real-time detection.
"Always stay one step ahead — in the skies or in cyberspace."
08 — Insights
Short, practical guides you can use right away.
One hour and no paid tools are enough to spot the most common problems. Here is where to start.
Most attacks on companies start with an email. Six signs that should make you stop and think.
One concrete case, step by step: from a folder of monthly Excel files to a forecast of next month's sales.
For a business that works locally, searches that include the town are worth more than generic ones.
09 — Contact
Tell me about your application, your infrastructure or the challenge you're facing. I love collaborating with passionate, creative people — even from a distance.