iiinova — where your digital self keeps evolving

Lucas Fernandes @vulgofoobar.bsky.social · 02/10/2026

does that means that there is no lazy loading and queries get executed anyway? for example, `Post.limit(10)` and `Post.includes(:comments).limit(10)`?

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Lucas Fernandes @vulgofoobar.bsky.social · 30/09/2026

query count is also something that degrades under production conditions. recently I've been diggin into N+1 query problems in Rails and here are my discoveries and learnings. ✨ check it out: vulgofoobar.tech/taxing-the-d... #devlife #learninpublic #database #performance #ruby

vulgofoobar.tech

Taxing the database with many queries also matters | Foobar

Introduction Recently, I've taking some mentoring classes and we've been discussing the N+1 query problems in Rails. Did you know that in…

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Lucas Fernandes @vulgofoobar.bsky.social · 09/09/2026

correctly! this also translates to: one request holding connection pool = bad for concurrent environment

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Lucas Fernandes @vulgofoobar.bsky.social · 06/09/2026

TIL: what features expand the context window? memory; multi-agent, each agent has it own memory; larger context window; summarization; projects n workspaces; skills n claude.md I'm still available for hire. let's talk! #ai #devlife #ruby #fediHire

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Lucas Fernandes @vulgofoobar.bsky.social · 01/09/2026

TIL: how does rails request interact w db? 1 request = n queries = n objects per query = borrows one connection from shared pool #ruby #performance #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 31/08/2026

TIL: why N+1 is bad every query pays network latency (worse across regions); CPU/IO spikes = rails framework overhead + db parse/plan/execute per query; db connection is expensive and hold it is bad for concurrent envs we really want to talk little to db! #performance #ruby #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 03/08/2026

TIL: what's eager loading? technique to load associations; in advance in the same query; into RAM #devlife #performance #ruby

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Lucas Fernandes @vulgofoobar.bsky.social · 30/07/2026

TIL: what is n+1 query? when collection access associations; additional query for each collection item; like sql being called inside a loop; we want to talk little to database as possible #devlife #performance

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Lucas Fernandes @vulgofoobar.bsky.social · 28/07/2026

TIL: what are the pros n cons of open source ai? pros: full control (privacy/run anywhere), cheaper, customizable, no vendor lock-in, auditable n innovation multiplier; cons: complex setup, hardware intensive, fewer out of the box capabilities n you manage security, scale and uptime #ai #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 16/07/2026

ai knowledge = consumed data + trained data. it has no knowledge ok? ok! #ai #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 15/07/2026

TIL: what are the signs that you approach the edge of the context window? slip long conversations and documents infos don't show up #ai #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 12/07/2026

TIL: what are behavioral fingerprints ai training leaves? sycophancy; verbosity; over-caution; loose confidence calibration #ai #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 08/07/2026

how to approach programming in a fun way? use tools and knowledge to deliver an end product; impact someone's life and enjoy the ride! ✨ #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 23/06/2026

I came up with this minimal theme for my new macOS menu bar that looks just like my Obsidian theme. 🤓 #sketchybar #macos #ui #customization

Obsidian window with a terminal-like theme featuring bright green text showing an "available for hire" note on Obsidian. The macOS menu bar above uses matching terminal-like styling, demonstrating a cohesive custom theme design across both the note-taking app and menu bar.

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Lucas Fernandes @vulgofoobar.bsky.social · 21/05/2026

TIL: what's the ai scaling laws? more computation power + more trained data = more performance + new abilities these explain a lot these days... #ai #devlife #softwareengineering

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Lucas Fernandes @vulgofoobar.bsky.social · 21/05/2026

TIL: why do llms hallucinate? llms are trained to predict text; they don't check facts against the training data and have no knowledge; training data has gaps, inconsistencies, and underrepresented topics. there is no intelligence in artificial intelligence 🙃 #ai #devlife #softwareengineering

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Lucas Fernandes @vulgofoobar.bsky.social · 18/05/2026

TIL: what are ai's capabilities and limitations? capabilities: conversational awareness, context switching without retraining and external tool integration. limitations are: hallucination potential, knowledge cutoff dates, complex reasoning challenges and context window constraints #ai #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 13/04/2026

I got my Ruby passport! ✨ it was nice talking to some of you at #tropicalonrails. thank you for conversations!

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Lucas Fernandes @vulgofoobar.bsky.social · 07/04/2026

@tropicalonrails.bsky.social, is there a place where I can park my bike at? 🤔

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Lucas Fernandes @vulgofoobar.bsky.social · 07/04/2026

I just got a ticket for tropical on rails! ✨ lesgooo! who am I gonna see there? #tropicalonrails #rubyonrails

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Lucas Fernandes @vulgofoobar.bsky.social · 06/03/2026

TIL: should I use single or double quotes in git commit messages? both works fine, but go for the single; double quotes might trigger "command substitution" on unix-like systems for example: ```bash echo "`ls`" ./docs/ ./node_modules/ ./package-lock.json ./package.json ./pages/ ``` #git #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 27/02/2026

I've been playing around with the `gum` gem from the `charm-ruby` ecosystem to glam up my scripts and aliases. I wrote a script that makes your scripts available from anywhere on your system. #ruby #gum #charmruby #devlife #nasa

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Lucas Fernandes @vulgofoobar.bsky.social · 26/02/2026

what are the exciting features in ruby 4 release? experimental `Ruby::Box` isolation mechanism; new zjit compiler; performance improvements for class instantiation; `Set` and `Path` classes promoted to core classes #ruby #devlife #softwareengineer

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Lucas Fernandes @vulgofoobar.bsky.social · 19/02/2026

TIL: what's git commit amend? does it modify the previous commit? it's like a time travel; rewrites the repo timeline; amend staged files to "previous" commit; previous commit is actually replaced and not modified; commits are immutable #git #softwareengineer #learninginpublic #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 08/01/2026

does privacy matter to you? do you want to be in control of your services? in this post, I’ll show you how to self-host your apps with minimal effort. the possibilities are endless! ✨ check it out: jaggies-weekly.netlify.app/how-to-self-... #devlife #learninpublic #selfhosting #linux #umbrel

jaggies-weekly.netlify.app

How to self-host your apps locally | Jaggies Weekly

TLDR 1. Prepare a bootable USB with the umbrelOS .iso and Balena Etcher 2. Boot your server device from USB 3. Install umbrelOS and remove…

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Lucas Fernandes @vulgofoobar.bsky.social · 24/12/2025

recently, I've been amazed by the UK jungle culture and what makes something jungle. I'm excited to share my first jungle track and actually, my first track ever! ✨ Check it out at: vulgovarios.bandcamp.com/album/modern... #jungle #cooking #music

vulgovarios.bandcamp.com

modern jungle, by varios

2 track album

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Lucas Fernandes @vulgofoobar.bsky.social · 05/12/2025

if someone asks me “why linux?” bc I'm the one in control; I can choose my desktop experience. want to look like Windows 98? that's possible too; no bloatware, no surprises; my data stays offline by default and no gossip behind my back; better performance #devlife #linux #wslisntlinux

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Lucas Fernandes @vulgofoobar.bsky.social · 12/09/2025

too late to talk about github’s recent absorption by micro$oft? it's never too late for a good article. right? _github is **not required**_ ignoring alternatives is risky. find a backup for your preferred tools blog.edwardloveall.com/lets-make-su... #softwareengineering

blog.edwardloveall.com

Let's Make Sure Github Doesn't Become the only Option - Edward Loveall

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Lucas Fernandes @vulgofoobar.bsky.social · 02/09/2025

TIL: about pure functions in functional programming depends only in its inputs; same input = always same output; no hidden state, no side effects, immutable (return a new thing instead of changing state) #ruby #functionalprogramming #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 27/08/2025

TIL: ruby, though dynamic, benefits from static type checking type checking occurs in runtime; ruby 3 adds .rbs files for type info; offers levels of checking; can use type profiler to detect type conflicts ruby abstracts type checking, keeping benefits without redundant declarations #ruby

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Lucas Fernandes @vulgofoobar.bsky.social · 14/08/2025

✨today I found out that I can theme vscode with CSS and inspect elements with devtools, just like we do in browsers. how cool is that? 🤓 an editor is a software that we use regularly in our daily lives. for me, any effort to make it appealing and easy to navigate is worth doing. #devlife #vscode

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Lucas Fernandes @vulgofoobar.bsky.social · 28/07/2025

I've just dropped a new blog post about how I practice vocabulary learning to retain more information and strengthen my brain connections. ✨ Check it out at: jaggies-weekly.netlify.app/how-do-i-pra... #learninginpublic

jaggies-weekly.netlify.app

How do I practice vocabulary | Jaggies Weekly

TLDR 1. Read and note unknown words (max. 5 per day) 2. Create flashcards: Front: word + original sentence Back: word meaning + sentences…

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Lucas Fernandes @vulgofoobar.bsky.social · 21/07/2025

TIL: automatic memory management with reference counting each memory has a reference count; when variables refers to it, increase count; stopping, decreases it; count == 0, memory freed; needs extra space per object; good for real-time apps, but can cause memory leaks #memorymanagement #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 18/07/2025

TIL: when system detects programs running low memory, it pauses program & runs garbage collector GC compacts heap, updates references & releases unreachable memory; uses "generations" where long-lived memory cleared less often; causes program random pauses; unsuitable for real-time apps #devlife

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Lucas Fernandes @vulgofoobar.bsky.social · 17/07/2025

manually deallocation = predictable performance = lower memory overhead = more bugs automatically deallocation = free the programmer from the burden = performance variations/overhead

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Lucas Fernandes @vulgofoobar.bsky.social · 17/07/2025

TIL: about memory leak it's when an allocated memory isn't deallocated and OS can't reclaim it; becomes unusable until program ends; long-running programs, leaks cause crashes; double-deallocation can corrupt active memory, causing security risks & unpredictable crashes #devlife #memorymanagement

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Lucas Fernandes @vulgofoobar.bsky.social · 14/07/2025

TIL: about memory management systems allocate and free memory during program execution; older languages lack automatic memory management, so programmers must explicitly handle it; one allocation = one deallocation; uses ram, cpu registers, cpu cache, and virtual memory #devlife #memorymanagement

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Lucas Fernandes @vulgofoobar.bsky.social · 11/07/2025

push CDN: requires engineering effort to propagate updates to the CDN caches; the first request is fast bc CDN server doesn't need to travel to the original server. more control over cache timing

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Lucas Fernandes @vulgofoobar.bsky.social · 11/07/2025

TIL: every CDN server has its own local cache with two main strategies to populate it pull CDN (most common): lazily fetches content, requires low maintenance, but the first request is slower and assets can become stale. cache busting helps if we don't want stale content #softwareengineer #cdn

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Lucas Fernandes @vulgofoobar.bsky.social · 11/07/2025

TIL: CDNs minimize latency for distant clients because there's always a CDN server nearby CDN = content delivery network; geographically distributed servers that cache assets from origin server efficiently; reduces bandwidth usage and server load; essential for global scale #softwareengineering

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Lucas Fernandes @vulgofoobar.bsky.social · 04/07/2025

Hey folks! 👋🏻 I'm available for hire! I can communicate effectively, I'm a passionate learner and love sharing knowledge. I'm looking for remote or on-site Mid-level or Semi-Senior Software Engineer roles, either part-time or full-time. Find out more: jaggies-weekly.netlify.app/im-available...

jaggies-weekly.netlify.app

I'm available for hire | Jaggies Weekly

I'm a Software Engineer with over 5 years of experience with a special focus on Ruby on Rails and SaaS products. I can communicate…

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Lucas Fernandes @vulgofoobar.bsky.social · 30/04/2025

TIL: nginx isn't just a load balancer, it's a web server, reverse proxy, cache, mail proxy & A/B testing tool. Despite its performance, misconfigs can actually add latency. watch settings: caching, proxy rules, complex routing, decryption, rate limiting. #softwareengineering #softwarearchitecture

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Lucas Fernandes @vulgofoobar.bsky.social · 29/04/2025

modernizing a legacy monolith? strangler fig pattern can help you with that without downtime. audit your system: evaluate the functionality; map all component dependencies; assess failure risks. #softwareengineering #softwarearchitecture

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Lucas Fernandes @vulgofoobar.bsky.social · 28/04/2025

TIL: there is a special architectural pattern called "strangler fig pattern" that facilitates the gradual replacement and modernization of legacy systems. #softwareengineering #softwarearchitecture

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Lucas Fernandes @vulgofoobar.bsky.social · 17/04/2025

solutions: use apache flink for distributed state management; use monitoring and observability tools like prometheus, grafana and confluent to track down and resolve issues; use a kafka "checkpoints" + exactly-once semantics to prevent data loss and duplication of events

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