Four ways a program becomes visible

Client-side rendering and the component web

CSR ships HTML, CSS, and JavaScript to the browser. The engine builds the interface. A first response may be a thin document plus a bundle; the page then fetches data and updates the DOM. React, Vue, and Angular live here.

WebAssembly changes what “client” can mean. Wasm is a stack-based binary format that runs near native speed. C++, Rust, Go, Java, and Kotlin can compile to it. WASI 0.2, developed under the Bytecode Alliance, introduces the Component Model. WIT files are the contracts that pass strings and handles between modules — a capability sandbox, not a free kernel.

Server-side rendering and first paint

SSR builds HTML on the server after business logic and a database query. The browser receives a complete document. Crawlers can read it. First Contentful Paint improves on a weak network. Next.js and similar hybrids serve the first paint from the server, then hydrate interactivity.

Systems executables

Rust, C, C++, and Go can leave the browser sandbox and talk to the kernel. Teaching that work usually means a real compiler and a guarded host. CodeLabs will not spawn rustc or gcc. The Rust lesson matches strings. Your machine runs cargo.

Data pipelines and DuckDB-Wasm

Pipelines extract, transform, and load. Clusters used to own that work. DuckDB-Wasm puts an analytical SQL engine in the browser, reading local Parquet through the Origin Private File System. The report cites architectures that can be far cheaper to operate than a remote warehouse. This terminal still will not execute SQL against a live engine — it only accepts the lesson string.

The quiet backbone

PostgreSQL is the dominant open-source relational store in recent surveys. Redis is the in-memory cache that grew with complex session and queue work. SQL remains the language of the question regardless of the frontend.

Glossary

CSR

The browser executes the interface after a thin first document.

SSR

The server assembles HTML before the first paint.

WASI

A system interface so Wasm can run with explicit capabilities.

WIT

The IDL that describes how Wasm components exchange rich types.