Ruby

Релизы Rails: 4.2.1, 4.1.10 и Ruby Together (подробнее на русском)
Simple Neural Network implementation in Ruby via the nmatrix gem и Using Neo4j with Ruby on Rails
Reading Rails — Time Travel и No Date.today? It’s DateTime!
Regression Driven Tests и Why Feature Testing is Important
Ruby Timeout, how does it even work? и Tracking down unused templates

JavaScript

Run Chrome Apps on Mobile Using Apache Cordova и Hamsa — a dead simple, data-binding and observable model
MuJS is a lightweight Javascript interpreter designed for embedding in other software to extend them with scripting capabilities и Motion sensing using the doppler effect
SVG Tools And Resources You Might Want To See и Textures.js — SVG patterns for Data Visualization
AniCollection — коллекция CSS-анимаций и We Will All Be Game Programmers (video)
Angular Basics (free book) и Your First Meteor Application (free book)