Programming Tutorials

I'm on a project where the file upload setup uses Active Storage with Amazon S3. But there's no configuration for me to download files from S3 and use

I had never built an app that needed to send SMS, but our last project at the firm required it. I talked to a friend about it and he told me about Twi

pluck No Rails, temos o pluck, que retorna um array com os valores dos atributos que você selecionou. Doctor.pluck(:id) (0.9ms) SELE

Modern Javascript uses a lot of libraries and processing tools, including NPM, Yarn and Webpack. So when you use React, you need all these tools. Rail

Brazil mandates that every business issuing goods or services emit an NF-e (Nota Fiscal Eletrônica) — a government-signed XML submitted to SEFAZ in re

Shopify data engineering interview questions are SQL end-to-end with a sharp merchant-sessions analytics edge: five SQL primitives (DATE_TRUNC('month'

PayPal data engineering interview questions are Python end-to-end with a payments-analytics edge: five Python primitives (list comprehensions for filt

Your agent has 40 tools. Each tool definition — name, description, JSON Schema parameters — costs roughly 200 tokens. That's 8,000 tokens before the a

The problem I wanted to solve Every automation tool I tried had the same issue: fire and forget. It sends the command and hopes for the bes

Last week, I finally snapped. Our “legacy” news aggregator was crawling 200 sites in 8 minutes, with two database timeouts along the way. Ops complain

Hyper data engineering interview questions are SQL end-to-end with a sharp retail-analytics edge: six SQL primitives (aggregation with ORDER BY ... LI

Here’s the story: last week my boss threw a “simple” task at me — pull data from 120 internal APIs simultaneously and compile a report. I thought, “Th

It happened last year when I was adding a “batch domain liveness check” feature to our internal operations platform. The requirement was simple: perio

Last Friday at 5 PM, right when I was about to close my laptop and sneak out, the alert channel exploded — the online data collection service had a ti

Last month, the data platform I maintain suddenly got a new requirement: run health checks against 100+ downstream services. Each endpoint averages 20

Here’s the situation: we have a data collection service that fetches data from a dozen upstream APIs. The synchronous version took a painful 30 minute

TL;DR Zod's .refine() executes on every input — even when earlier validators like .min() and .max() have already failed. If you place an ex

Last week I was building an internal monitoring tool that needed to fetch pages from over 200 websites concurrently. Our old synchronous script took m

This article was originally published on Jo4 Blog. We found three authentication bugs in production. Not from penetration testing. Not from a secur

This article was originally published on Jo4 Blog. Our OAuth implementation worked perfectly. Every test passed. Users authorized apps, got tokens,