Jacar is a technical blog about DevOps, applied AI, Kubernetes, observability, security and product design, written by Javier Cañete from Madrid in Spanish and English.

Javier Cañete Arroyo, CEO of Jacar Systems S.L., with 20+ years in infrastructure, cloud platforms and software architecture. More at jacar.es/en/sobre/.

What topics does Jacar cover?

Cloud-native platforms (Kubernetes, Docker, Traefik), applied AI (LLMs, RAG, embeddings, vector DBs), observability (Prometheus, Grafana, eBPF), security (NIS2, supply-chain, zero trust) and product design.

Is it available in English?

Yes. Every article is published in Spanish as canonical and in English under /en/ /, with hreflang declared so each language serves its audience.

How often does it publish?

A new article every 2-3 days, edited — no filler. The last_reviewed date in the frontmatter reflects when the metadata was last verified.

How can I get in touch?

Via LinkedIn (linkedin.com/in/javiercanetearroyo) or the contact page at jacar.es/en/contacto/. For business, jacarsystems.com/.

Madrid · ES/EN · async-first

DevOps &

Honest infrastructure for small teams. No theatre, no slides, with code that stays with you.

NIST PQC: The Post-Quantum Cryptography Standards

NIST publicó los primeros estándares PQC en agosto de 2024: ML-KEM, ML-DSA y SLH-DSA. Qué significa para tu stack de seguridad y cómo prepararse para la transición.

Tecnología

1.9K 12 min November 16, 2024 4.4

How to install Portainer with Docker Compose v2

Portainer es la UI web de referencia para gestionar contenedores Docker, stacks de Compose y clusters Swarm/Kubernetes. Guía paso a paso con compose.yaml moderno, HTTPS en el puerto 9443, volumen nombrado y configuración opcional con Traefik.

Cómo Instalar

1.9K 10 min April 19, 2026 4.7

Next-generation NPUs: the hardware moving AI in 2026

Las NPU dejaron de ser un accesorio para convertirse en el componente que define rendimiento real en portátiles, teléfonos y servidores pequeños. Repaso práctico del hardware que domina 2026, qué cargas compensan y dónde sigue ganando la GPU tradicional.

Tecnología

1.2K 12 min March 17, 2026 4.9

How to install and tune oMLX on M5 Max 128 GB

Tested May 2026 recipe: oMLX 0.3.8 on Mac M5 Max with 128 GB, TurboQuant at 3.5-bit, Qwen 3.6 35B-A3B model stack, Claude Code wiring and real benchmarks.

Inteligencia Artificial

1.0K 26 min May 17, 2026 5.0

XR, AR and VR in 2026: the honest state after the cycle

Después del ciclo de hype de 2023-2024 con Apple Vision Pro como protagonista, del valle de desilusión en 2025 y de la consolidación discreta pero real de Meta Quest 3S y del stack WebXR, toca evaluar honestamente dónde está la realidad extendida. Qué funciona, qué se ha muerto, qué sigue vivo.

Experiencia de Usuario

893 13 min February 9, 2026 4.8

DPO and alternatives to RLHF: practical state in 2026

Direct Preference Optimization and its relatives have displaced RLHF as the preferred alignment method in much of the ecosystem. This is the practical state of the field in 2026.

Inteligencia Artificial

758 5 min 28 Apr 4.7

Essential Software for Your New M5 Mac (2026 guide)

100 must-have apps for your M5 Mac organised into 20 categories: browser, notes, terminal, IDE, containers, AI and more. Each pick with purpose, key features, plugins, pricing in EUR and the official link.

Herramientas

675 225 min 01 May

Claude’s Computer Use: When the Agent Moves the Mouse

Anthropic lanzó Computer Use en octubre de 2024: Claude controla el escritorio. Qué funciona, qué no, y las implicaciones reales para automatización.

Inteligencia Artificial

610 12 min 23 Oct 4.4

How to install Coolify on Docker (2026 step-by-step guide)

Coolify es una plataforma autohospedada que replica la experiencia de Vercel o Heroku sobre tu propia infraestructura. Esta guía instala Coolify 4.x paso a paso con Docker en Ubuntu 24.04.

Cómo Instalar