Backend Developer and Machine Learning Engineer
Federico Calò
Building robust backends, machine learning pipelines and AI privacy-focused tools
Spring Boot · Angular · Python · on-prem RAG and Ollama. A technical hub with 702 articles, 556 free dev-tools, an AI Knowledge Hub and open data datasets.
A separate category
No generic roadmaps, introductory courses, or AI-written content: here every concept comes from a monorepo with three real production microservices, with architectural choices verifiable in the code.
Backend production-ready
Clean Architecture with 4-layer defense from ArchUnit in CI, Flyway migration with real post-mortems, multi-layer security: not a tutorial, a real production Spring Boot system.
Frontend Architecture for Real Systems
Angular 21 SSR with hundreds of prerendered routes, Core Web Vitals measured, and enterprise-level i18n: the expertise that completes the stack, not the site headline.
IT career paths
Series focused on mid-to-senior jump and non-CS to dev path, with practical decision-based trade-offs: career is built with judgment, not just a degree.
What can you do on the platform
Technical Articles
702 articles on Angular, Spring Boot, ML, AI and architecture.
Development Tools
556 free tools: calculators, generators, validators.
Browser Extensions
52 free extensions for Chrome and Firefox: dev-tools, SEO, accessibility and on-prem AI. 100% offline, zero telemetry.
Open Data Dataset
High quality dataset for research, machine learning training and analysis.
Knowledge Center
Knowledge Pack for LLM, RAG Agent, Claude Projects and Copilot.
Interactive Arcades and Tools
Visual tools and simulators for learning technical concepts.
University
Transcriptions and notes from 3 Italian universities (10,009 lectures).
Premium Services
Subscription, Audit, Data API and Paid Knowledge Packs.
Business Tools
17 sectoral tools: finance, health, HR, real estate, law and more.
Professional services
Custom web development, technical SEO and business automation for clients and companies.
Computer Science Tutoring
Lessons for middle and high school students: theory (algorithms, flowcharts) and practice (Java, C, C++, HTML, CSS).
Platform ecosystem
Blog and Data Resource Center
702 technical articles on Angular, Spring Boot, Python and Machine Learning, Knowledge Packs optimized for LLMs and RAG, and open data datasets ready for training and analysis.
556 Development Tools
556 free in-browser tools: tax and payroll calculators for 23 countries, IBAN and tax-code generators, validators and SEO tools. No sign-up required.
Explore 556 Dev ToolsServices & Software as a Service (SaaS)
Technical newsletter, code and performance audits, Dataset API and paid Knowledge Packs for teams and professionals who want to speed up development.
Explore Premium ServicesArtificial Intelligence and Machine Learning on-premise
On-premise RAG and LLMs with Ollama and FastAPI: privacy-first chat, recommendations and semantic search, with no data sent to US clouds and zero API costs.
Read articles on AI & MLUniversity and Arcade
11,009 university lectures transcribed from 3 Italian universities, plus interactive visual tools to learn technical concepts step by step.
Detailed Areas
Each zone is free and designed for developers, researchers, and professionals.
556 Free Dev-Tools
Tax calculators for 23 countries, IBAN generators, validators, SEO tools and more. No registration.
Data set open data
Download CC-BY-4.0 datasets ready for ML training, analysis, and research. CSV and JSON formats, updated regularly.
University notes
11,009 transcribed lectures from 3 Italian universities. Computer science, math, economics, and engineering. Free and indexed.
Professional services
Web Development Angular SSR, Technical SEO, Business Automation and Architectural Consultation. Contact me for a quote.
Technical eBooks
Practical guides on Angular, Spring Boot, AI, and security. Updated with latest best practices and enterprise patterns.
Ask AI - Knowledge Center
Query the Knowledge Hub with on-prem RAG: answers based on 702 articles, total privacy, zero cloud latency.
Services for businesses
From MVP to on-prem AI: bespoke development, automation and technical consulting. Production-grade stack, direct communication, verifiable quality.
MVP & digital product creation
From concept to a production-ready, validatable product. Scalable architecture and fast delivery.
Full-stack web development (SSR)
Websites and web apps with Angular SSR and Spring Boot. Lighthouse 90+ performance and optimal SEO.
Custom / bespoke software
Management systems, internal tools and specific integrations. No templates: designed around your domain.
SEO analysis & optimization
Technical audit, structured data, Core Web Vitals and content strategy. Measurable results.
Automation & integrations
Automated workflows, data pipelines and integration between heterogeneous systems via REST/webhook.
Data & Machine Learning / AI (on-prem RAG)
RAG with on-prem Ollama, semantic embeddings and vector search. AI without vendor lock-in.
Recent blog posts
Deep dive into Angular, Spring Boot, AI, security, and cloud-native architecture.
As featured in
My work is published and citable on high-authority open platforms, used by researchers and AI models around the world.
Why use our platform?
Privacy-focused and self-hosted.
On-prem AWS on VPS: No data sent to US Cloud, Zero API costs.
Free tools, immediately operational.
556 Dev Tools in the browser, no registration or subscription required.
Frequently asked questions
Quick answers to common questions about tools, AI, privacy, and premium plans.
Are the tools and contents really free?
Yes. The 556 dev-tools, the 702 tech articles and the university notes are free and registration-free. Premium plans (newsletter, audit, dataset-credits) add optional advanced features.
How does on-prem AI work? Are my data private?
Yes. The AI model (llama3.1:8b) runs on Ollama installed on the Hetzner VPS in Europe. No data is sent to OpenAI, Anthropic, or Google. Zero API costs, no profiling.
In how many languages is the site available?
The portal is available in 18 languages: Italian, English, Spanish, French, German, Portuguese, Swedish, Norwegian, Russian, Ukrainian, Dutch, Polish, Czech, Romanian, Turkish, Japanese and Korean.
Are open data datasets freely downloadable?
Yes. The datasets are released under the CC-BY-4.0 license and downloadable in CSV and JSON formats. Premium dataset credits provide access to advanced query APIs and enriched datasets.
How do I start using the platform?
You can start now without signing up: explore the dev-tools, read articles or browse the Knowledge Hub. For advanced features (AI chat, audit, dataset API), create a free account.
What does the Premium Newsletter plan include?
For €8 a month get a weekly technical newsletter with in-depth articles on Angular, Spring Boot, AI, and security, article previews, commented code, and priority access to the Telegram channel.
Explore Urbex & Lost Places
An interactive free map with 30 documented abandoned places: factories, castles, hospitals and more. Filter by category and risk level. For documentation and research only.
Open mapStart exploring the ecosystem
Create a free account and access all premium tools and content.
Platform impact
Real data, no vanity counters. Measured on organic traffic and active production.
Privacy-focused AI on-premises
RAG with Ollama on Hetzner VPS: zero US cloud data, zero API costs. Adopted as reference architecture for EU AI Act compliant tech portals.
Multilingual SEO and automatic hreflang
Angular SSR AOT + Transloco runtime: 1.014 routes prerendered in 2 build locales, hreflang auto and dynamic sitemaps for 702 articles.