SEO
Canonical and hreflang: how to implement them properly (and the mistakes that cancel them)
What the canonical tag does, what hreflang does, how to combine them on a multilingual site with x-default, and the mistakes that make Google ignore them.
Author
Aimran Oukham
Full-stack developer based between Valencia and Alicante, creator and maintainer of the AIMRAN ecosystem: aimran.es, AIMRAN Tools, AIMRAN Library and AIMRAN Universe.
What Aimran does
Aimran is the person who builds and maintains the projects of the AIMRAN ecosystem. All of them are live and can be visited:
- aimran.es: the main website, with information about Aimran and his projects.
- AIMRAN Tools: online tools for developers that run in the browser.
- AIMRAN Library: a library of components and resources for web projects.
- AIMRAN Universe: the map of the ecosystem and its projects.
- AIMRAN Blog: this blog, where he documents what he learns building and maintaining all of the above.
Background
As he explains on aimran.es, Aimran has spent four years building websites and managing servers, has delivered more than 130 projects (many for agencies and companies) and, in parallel, is studying Multiplatform Application Development while building his own products. His usual stack includes React, TypeScript, Supabase, WordPress and WooCommerce, plus infrastructure and technical SEO.
Why he writes about these topics
The blog’s topics (web development, applied artificial intelligence, developer tools, technical SEO and technology) are exactly what he works on every day while building and maintaining those sites. Articles grow out of concrete problems solved in those projects, not keyword lists.
When an article depends on external information (Google documentation, web specifications, a tool’s release notes), the original source is linked so you can check it.
How to get in touch
Articles written by Aimran
18 articles
Web development
Docker: the difference between an image and a container, explained with commands
What a Docker image is, what a container is and how they relate, with the basic commands to create, list, stop and remove each one, plus the most frequent mistakes.
Web development
How to undo the last commit in Git without losing work
How to undo the last commit in Git with reset, revert and amend, which one to use when the commit is already pushed, and how to recover a commit you thought lost.
Artificial intelligence
How a language model works: tokens, context window and temperature
What a token is, what the context window limits, what temperature does and why language models are confidently wrong. Explained for developers, no maths.
Web development
How to convert images to WebP (and when not to)
What WebP is, how much it saves over JPEG and PNG, how to convert images in the browser, the terminal or Node.js, and how to serve them with picture.
Artificial intelligence
How to count the tokens in a prompt and estimate what a call to a language model costs
Why models charge per token, how to count tokens exactly for GPT and approximately for Claude, and how to cut the cost of each call without losing quality.
Developer tools
How to read and write a cron expression (with examples you can copy)
What each of the five fields of a cron expression means, what *, comma, hyphen and slash do, the mistakes that confuse most people and ready-made examples to copy.
Developer tools
How to validate JSON and understand its most common errors
JSON syntax rules according to the standard, the five mistakes behind almost every parse failure, and how to validate a file in the browser, terminal or Node.js.
Technology
HTTP security headers: which ones to set on any website and what each does
What HSTS, Content-Security-Policy, X-Content-Type-Options, X-Frame-Options, Referrer-Policy and Permissions-Policy do, with recommended values and checks.