Tags: web-dev map

Languages MOC

Date: 2026-08-16

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One folder each. Each holds a reference — the language mapped rung by rung — plus concepts for the durable models that language exposes better than the others. What belongs here: the reference, and concepts genuinely about that language’s model. What doesn’t: patterns expressible anywhere, which are Foundations. A closure is a JavaScript note; a state machine isn’t.

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JavaScript

The one that has to be deepest, because everything client-side runs through it.

• Reference - JavaScript — the language mapped
• Closures — the mechanism, and the practical uses that make it worth understanding
• Prototypes and Inheritance — what class is sugar over
• this and Binding — four rules, one permanent source of confusion
• Promises and Async Await — the model, and the error handling that catches people out
• Modules — ESM versus CommonJS, and the interop mess between them
• Iterators and Generators — lazy sequences and the protocol behind for...of
• Equality and Coercion — == versus ===, and the coercion table worth knowing once
• Scope and Hoisting — var, let, const, and the temporal dead zone

TypeScript

• Reference - TypeScript — the type system mapped
• Structural Typing — the core idea, and how it differs from the nominal typing most languages use
• Generics — parameterised types, and the point at which they stop helping
• Type Narrowing — how the compiler learns what something is inside a branch
• Utility Types — the built-in transformations worth memorising
• Type Safety Boundaries — where types stop being guaranteed: any, assertions, and anything from the network

CSS

• Reference - CSS — the language mapped
• The Cascade and Specificity — origin, layer, specificity, order. The four-step answer to “why isn’t this applying”
• The Box Model — content, padding, border, margin, and box-sizing
• Flexbox — one-dimensional layout, and what the properties actually do
• Grid — two-dimensional layout, and when it beats flex
• Positioning and Stacking Contexts — the reason z-index doesn’t work
• Container Queries — component-scoped responsiveness, replacing most breakpoint work
• Custom Properties — runtime variables, and how they differ from preprocessor variables
• Cascade Layers — controlling override order deliberately rather than by specificity war
• Fluid Type and Space — clamp() and the scale it makes possible
• Logical Properties — writing-direction-aware CSS, and why it’s the better default
• Responsive Design — breakpoints as a last resort, intrinsic sizing as the default
• CSS Architecture — BEM, utility-first, CSS-in-JS: what each optimises for

PHP

• Reference - PHP — the language mapped
• The Request Lifecycle in PHP — the shared-nothing model, and everything that follows from dying after each request
• Composer and Autoloading — dependency management and PSR-4
• PHP Type Juggling — the comparison rules, and the security bugs they’ve caused

C#

• Reference - C# — the language mapped
• The Common Language Runtime — compilation, JIT, and managed memory
• LINQ — query syntax over collections, and deferred execution
• Async in C# — async/await over a thread pool, contrasted with JavaScript’s single thread

Liquid

• Reference - Liquid — the language mapped, Shopify flavour, base-gem differences marked

SQL

• Reference - SQL — the language mapped
• Joins — the four kinds, drawn as row sets rather than described
• Window Functions — computing across rows without collapsing them; the tool most analytics work actually needs
• Common Table Expressions — naming intermediate results, and readable recursion
• Aggregation and Grouping — GROUP BY, HAVING, and the ordering of evaluation that explains most errors
• Query Performance — the handful of rewrites that fix most slow queries, and why warehouse cost is bytes rather than time
• SQL Dialects — where Postgres, MySQL, BigQuery and SQLite diverge on things you’d assume are standard

Borders

Filed elsewhere, needed constantly here.

• Foundations — The Relational Model · Indexing · Query Planning · N+1 Queries · Type Systems · Garbage Collection
• Performance — Memory and Long Sessions — closures, listeners and detached nodes: JavaScript’s leaks
• Tooling — Package Managers · Lockfiles · Supply Chain Risk · Static Analysis
• Analytics — Sessionisation · Double Counting · Warehouse-First Analytics