developwith

AWS

How to set up GitHub Actions to build a Docker container and push to AWS ECR

Create a GitHub Actions workflow that builds a Docker image, authenticates with AWS, and pushes to Elastic Container Registry (ECR) on every push to main.

Jetpack Compose

How to create a Hello World app with Jetpack Compose

Build a minimal Jetpack Compose app from scratch — understand every file, every composable, and every piece of the puzzle.
How to manage state in Jetpack Compose

Using remember, mutableStateOf, StateFlow, ViewModel, and state hoisting patterns in Compose
How to navigate in Jetpack Compose

Using Navigation Compose for type-safe routing, nested graphs, deep links, and bottom navigation
How to set up Jetpack Compose in your project

Adding Compose dependencies, configuring the build, and writing your first composable
How to use Material Design 3 in Jetpack Compose

Applying Material 3 theming, color schemes, typography, and components in Compose
How to write tests in Jetpack Compose

Testing composables with semantics, assertions, and UI automation in Compose

Flutter

How to create a Flutter project and run it

Setting up a new Flutter project, configuring editors, and running on emulators and devices
How to make network requests in Flutter

Using the http package, Dio, and parsing JSON with code generation in Flutter
How to manage state in Flutter

Choosing and using state management approaches in Flutter — setState, Provider, Riverpod, Bloc, and Signal
How to navigate between screens in Flutter

Using Navigator 1.0, named routes, and GoRouter for declarative navigation in Flutter
How to persist data locally in Flutter

Using SharedPreferences, Hive, sqflite, and Drift for local data persistence in Flutter
How to write and run tests in Flutter

Unit tests, widget tests, integration tests, and mocking in Flutter

Mobile

How to publish an app to the Apple App Store

A complete end-to-end guide covering Apple Developer accounts, certificates, provisioning profiles, App Store Connect, signing, and submission.
How to publish an app to the Google Play Store

A complete end-to-end guide covering Google Play Developer accounts, signing keys, AAB/APK builds, Play Console metadata, and submission.

AI

How to create an AI agent with LangChain and LangGraph

Build a tool-using AI agent using LangChain and LangGraph in Python and TypeScript
Generating Posts and Apps with AI

How to use AI to generate blog posts, social media content, technical articles, and code snippets — with tips for writing effective prompts.
What is Machine Learning?

A beginner-friendly introduction to machine learning — how algorithms learn from data to make predictions, with everyday examples like spam filters and recommendation systems.

Ruby

Run SQL updates in Rails migration

An approach to running rails migration sql code after adding a column
Pass a variable to a partial in Rails

Dynamic behavior from parent template to partial via parameter passing in Rails.
Http status Codes in Rails

A list of http status codes in rails
Add Character Encoding to Heroku buildpack

Using charlock homes library in your heroku application
Add Image Processing to Heroku buildpack

Process images in your heroku application
Cancel Recurly Subscription Programmatically

Different ways to cancel a recurly subscription using the ruby sdk.
Cancel Recurly Subscription Programmatically

Different ways to cancel a recurly subscription using the ruby sdk.
Convert a string to class

Change a string into a class reference in ruby
Custom Ruby buildpack

Adding compilation steps to ruby build pack for heroku
Custom tag with attributes in Jekyll

Process attributes in a tag within Jekyll
Eager load children in ActiveRecord

Using includes to eager load active record relationships
Fix Issue with Psych Yaml gem on RVM and OSX

How to fix the issue with path2class error using RVM and OSX
Fix the handlebars.vm error

Mismatches of gems sometimes cause issues with handlebars.vm or other gems
Flatten a Hash into a String

Using join to create a key value string
Recover a Load Error

Installing a gem from a load error
Rspec tips and tricks

How to run multiple and individual tests. How to add details to the tests.
Size of active record collection

Know the size method to use for activerecord lists
Unique list with records

When you need to have a uniq array with a given set of records
Url encode strings

Using standard ruby features to encode strings
Use modules for testing

An approach to mocking behavior can be using modules to mock interactions

Kotlin

How to get started with Spring Boot

Using Spring boot with Kotlin
How to override the TypeIdResolver in Jackson

Sometimes when the field isn't present in json the type resolving fails.
How do I configure jackson object mapper?

Using Jackson and Spring to configure and Object mapper with Kotlin.
How to use Mockk in Testing

Using mockk to make testing easier
How nest annotations with kotlin

Nested annotations in Kotlin are a bit tricky if you don't know what to do.
How to create lists in Kotlin

Using lists and arrays in kotlin

Java

How to generate test numbers in Java

Using Google Phone Utils
How to use certs with Java keystore

Using certs and migrating certs from different version and debugging with keytool.
Gotchas with numbers in Java

Using numbers in Java can be tricky if you don't know what shadowing is doing with them.
How to change JPA Id Generator

Using hibernate sequence generator to change the behavior of the id generation.
How to disable Redis loading in Spring boot

When you don't want your app to fail on redis connections on startup.
Spring Autowiring Tips

How to support null properties, clean up component scan and nullable beans
Using JPA to make an IN Query

How to query a database table with an IN statement in JPA.
How to load a file into a String

Using Apache Commons IO for copying streams and loading a file into a String.
How to use a simple string template in java

Using Apache Commons Lang for simple string templates

Unix

How to resolve dependencies in apt-get

Resolve all dependencies when installing a package with apt-get.
Setup a Serverless Runtime

Serverless applications need a place to run — how do you set that up?
Decrypt GPG data

How to decrypt data that is base64 encoded and gpg encrypted.
Flush Memcached

How to flush memcached

Databases

Using HSQL with Array columns

How to use HSQL with array columns in Hibernate and PostgreSQL.
Using Left Join with HQL

How to use left joins in Hibernate Query Language (HQL).
Using Postgres Array columns

How to use array columns in postgres effectively.
Using Postgres Identity columns

How to use identity columns in Postgres effectively, including UUID alternatives.
Debugging Postgres Sequences

How to determine if your postgres sequences are working.
Restore local mysql db

Restoring a corrupt mysql db based on laptop sleeping or other inproper shutdown scenarios
Setup Memcached

Setup and configuring memcached for development
Setup Postgres

Setup and configuring a postgres server for development
Setup Redis

Setup and configuring redis for development

Postgres

Using Postgres Array columns

How to use array columns in postgres effectively.

Git

How to remove files from Git history

Opps you put some sensistive data in your git repo.
Export files from github

Archive a remote repository into a directory
Ignore file in Git

Excluding files from a git repo

Architecture

Use Seamonkeys as architecture case study

Non-proprietary case study to evaluate architectural concepts

Dart

How to create and run a Dart project

Set up a new Dart project, add dependencies, and run it
How to make network requests in Dart

Fetch data from APIs using Dart's built-in http package
How to work with files and paths in Dart

Read, write, and manipulate files using the dart:io library
How to write and run tests in Dart

Set up and write unit tests using Dart's built-in test package

Elixir

How to query with joins, group_by, and pipe-style Ecto

Write readable Ecto queries using the pipe operator with joins, group_by, having, and aggregates in Phoenix applications.
How to use IEx to query the database in Phoenix

Start an IEx session connected to your Phoenix app's Ecto repo and run queries interactively for debugging, exploration, and development.

Mac

How to fix Adobe Illustrator on macOS with Java 7

Resolve the Java runtime prompt that prevents Adobe Illustrator from launching on macOS by installing the correct Java version.
How to set JAVA_HOME on macOS

Set the JAVA_HOME environment variable on macOS so Java-based tools and applications can find your JDK installation.

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LeetCode Study Guide

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