Intermediate code explainers

go

package email
 
import (
	"errors"

Normalizing and deduping email addresses in Go

validation normalization deduplication

Intermediate 8 steps

java

@Configuration
@EnableBatchProcessing
public class CustomerImportJobConfig {

How a chunk-based CSV import job works in Spring

batch-processing etl csv-parsing

Intermediate 9 steps

ruby

class TasksController < ApplicationController
  before_action :set_project
 
  def reorder

Bulk task reordering with upsert_all in Rails

bulk-update upsert authorization

Intermediate 8 steps

php

<?php
 
namespace App\Support;

Recursively finding files with SPL iterators in PHP

recursion iterators filesystem

Intermediate 7 steps

python

from contextlib import contextmanager
from typing import Iterator
 
import psycopg2

Streaming Postgres rows with a server-side cursor

generators context-managers database-streaming

Intermediate 7 steps

rust

use std::time::Duration;
 
use axum::{
    http::{header, HeaderValue, Request},

Serving fingerprinted assets in Axum

static-assets http-caching middleware

Intermediate 7 steps

typescript

type MatchSegment = {
  text: string;
  matched: boolean;
};

Splitting text into highlighted match segments

regex string-matching text-highlighting

Intermediate 8 steps

javascript

const express = require('express');
const multer = require('multer');
const path = require('path');
const crypto = require('crypto');

Safe image uploads with Multer in Express

file-upload multer validation

Intermediate 7 steps

go

type PostCursor struct {
	CreatedAt time.Time
	ID        int64
}

Keyset pagination with cursors in Go

pagination keyset-cursor database

Intermediate 8 steps

java

@Configuration
@EnableWebSecurity
public class ResourceServerConfig {

Configuring a JWT resource server in Spring

oauth2 jwt authorization

Intermediate 8 steps

ruby

require "openssl"
require "json"
require "base64"

Building signed session tokens in Ruby

hmac authentication cryptography

Intermediate 8 steps

php

<?php
 
namespace App\Http\Requests;

A validated date-range value object in PHP

value-object validation immutability

Intermediate 7 steps

rust

use std::collections::VecDeque;
 
#[derive(Debug)]
pub struct Hunk {

Applying a diff hunk in Rust

enums error-handling pattern-matching

Intermediate 8 steps

typescript

import { Component, input, computed } from '@angular/core';
 
function toNumber(value: number | string): number {
  return typeof value === 'number' ? value : parseFloat(value);

Signal inputs and computed in Angular

signals reactivity derived-state

Intermediate 5 steps

go

package config
 
import (
	"fmt"

Parsing timeout config in Go

configuration validation error-wrapping

Intermediate 7 steps

java

@Configuration
public class OrderConsumerConfig {
 
    @Bean

Wiring a resilient Kafka consumer in Spring

kafka deserialization error-handling

Intermediate 8 steps

ruby

class Product < ApplicationRecord
  belongs_to :category, touch: true
 
  has_many :reviews, dependent: :destroy

How Rails models wire up associations

active record associations validations

Intermediate 7 steps

typescript

import sanitizeHtml from "sanitize-html";
 
interface RichTextOptions {
  allowImages?: boolean;

Building a configurable HTML sanitizer allowlist

sanitization xss-prevention allowlist

Intermediate 7 steps