Examples

This page tracks the examples this implementation targets. The compatibility goal is that every example on <https://elm-lang.org/examples> works across the applicable backends; beyond that catalogue, the project ships its own larger apps and command-line/server demos (listed at the bottom). Slugs are the path under /examples/<slug>. The "Needs" column tracks the runtime capability each example requires, which drives implementation order.

Status: ✅ = working & tested headlessly (interpreter/bytecode), ⏳ = not yet.

#	Category	Title	Slug	Status	Needs
1	HTML	Hello	`hello`	✅	Html.text only (static)
2	HTML	Groceries	`groceries`	✅	Html elements (static)
3	HTML	Shapes	`shapes`	✅	Svg (static)
4	User Input	Buttons	`buttons`	✅	Browser.sandbox, onClick, update
5	User Input	Text Fields	`text-fields`	✅	Browser.sandbox, onInput, String fns
6	User Input	Forms	`forms`	✅	Browser.sandbox, multiple fields, styles
7	Random	Numbers	`numbers`	✅	Browser.element, Cmd, Random
8	Random	Cards	`cards`	✅	Random, custom types
9	Random	Positions	`positions`	✅	Random.map2, Svg
10	HTTP	Book	`book`	✅	Browser.element, Http.get, text (stubbed response)
11	HTTP	Quotes	`quotes`	✅	Http, Json.Decode (map4/field/int/string)
12	Time	Time	`time`	✅	Browser.element, Time, subscriptions, Task
13	Time	Clock	`clock`	✅	Time, Svg, subscriptions
14	Files	Upload	`upload`	✅	File input + decoder; driven with stub files
15	Files	Drag-and-Drop	`drag-and-drop`	✅	File.Select + hover state; stub files
16	Files	Image Previews	`image-previews`	✅	File.toUrl + Task.sequence → data URLs
17	WebGL	Triangle	`triangle`	✅*	runs; builds mesh/matrices, emits `<canvas>`
18	WebGL	Cube	`cube`	✅*	webgl, Mat4 transforms
19	WebGL	Crate	`crate`	✅*	webgl + stub texture (Task.attempt)
20	WebGL	Thwomp	`thwomp`	✅*	webgl, two textures, viewport
21	WebGL	First Person	`first-person`	✅*	webgl, keyboard, toHtmlWith
22	Playground	Picture	`picture`	✅	real evancz/elm-playground loaded via module system, rendered to SVG
23	Playground	Animation	`animation`	✅	elm-playground; renders initial frame (octagons + bar)
24	Playground	Mouse	`mouse`	✅	elm-playground game; initial frame
25	Playground	Keyboard	`keyboard`	✅	elm-playground game; initial frame
26	Playground	Turtle	`turtle`	✅	elm-playground game + image
27	Playground	Mario	`mario`	✅	elm-playground game + sprite image

✅* = the program runs and produces the scene (meshes, matrices, entities) and a <canvas> element, verified headlessly. Actual rasterized pixels require a real GPU/WebGL context, which a headless JVM cannot provide.

Gallery (compiled JavaScript)

The static gallery at <https://tunguski.github.io/elm-lang/> presents the JS-compiled output of each example, generated by SiteGenerator and published by the Pages workflow. 20 of the 27 run as live compiled JavaScript in the browser; the multi-module Playground games (22–27) and the keyboard-driven First Person (21) currently fall back to an interpreter-rendered initial frame.

Beyond the catalogue

The gallery also showcases larger, hand-written apps that exercise the backends end to end:

RTS Mini — a small but functional real-time strategy game (its own project+repo: github.com/tunguski/elm-rts, checked out under projects/elm-rts): build buildings, train units, gather resources (a worker walks a BFS path around water/rock to a mine, hauls loads back to base and deposits them) and uncover the whole map to win. It's cleanly split into RTS.Model / RTS.Logic / RTS.View / RTS.Main, with an optional RTS.Backend HTTP handler that shares the model. The page is the JS-compiled game running entirely in your browser — no server needed.
TodoMVC — the flagship TEA app.
Elm-in-Elm editor — an Elm interpreter written in Elm, with live evaluation and syntax highlighting. Its own project+repo (github.com/tunguski/elm-editor, checked out under projects/elm-editor); the gallery builds it from there when present.

Backends

JIT interpreter — Truffle language (TruffleLanguage, self-specializing AST nodes). On GraalVM the Graal compiler partial-evaluates hot nodes, giving a real JIT.
Compiler to JavaScript — textual JS codegen plus a small kernel runtime, mirroring the approach of the official Elm compiler. This is the path that can realistically run the browser/WebGL/Playground examples.
Compiler to bytecode — Truffle Bytecode DSL interpreter (GraalVM bytecode generator).

Notes on feasibility

Examples 1–16 are achievable headless: pure rendering and The Elm Architecture (TEA) with Cmd/Sub/Http/Time/File effects, verified by driving update/view and inspecting the resulting virtual DOM (interpreter/bytecode) or generated JS run under Node with a DOM shim.
Examples 17–21 (WebGL) and 22–27 (Playground) depend on external Elm packages (elm-explorations/webgl, evancz/elm-playground) and a real rendering surface; these are tackled last and primarily via the JS backend.

Beyond elm-lang.org

The browser examples above are the compatibility target, but this implementation also runs Elm *outside* the browser. These bundled demos exercise the non-browser backends and have their own guides:

Demo	Run with	Demonstrates	Guide
`WordCount`	`elm script WordCount <files…>`	A `wc`-style CLI script (stdin/files/args/exit code).	scripting.md
`FolderReport`	`elm script FolderReport <dir>`	Recursively walks a directory and summarises it (counts, total size, largest files, by extension) using the structured `Bash`/`Posix` `find`.	scripting.md
`BigFiles`	`elm script BigFiles [threshold] [dir]`	Lists files over a line threshold (default 1000), largest first — `find` + `wc` over a directory.	scripting.md
`AwkSum`	`elm script AwkSum <col> <file>`	Composes an `awk` program with the `Awk` builder (sum a column).	scripting.md
`CsvReport`	`elm script CsvReport <file.csv>`	Parses CSV with the `Csv` library and renders it to an HTML table via `Site`.	scripting.md
`M4Expand`	`elm script M4Expand <name>`	Generates an `m4` macro program with the `M4` builder.	scripting.md
`SimpleServerShowcase`	`elm server SimpleServerShowcase`	A stateless HTTP app: routing on path/query, `text`/`html`/`json`.	server.md
`LiveDashboard`	`elm server LiveDashboard`	A stateful server: in-memory time series, a timer-driven random walk, and a self-updating SVG chart polled by the client.	server.md
editor	open `editor.html` in the gallery	An in-browser, multi-file Elm playground with a from-scratch Elm interpreter and a time-travel debugger.	—

A bundled demo name (e.g. WordCount, LiveDashboard) resolves to the shipped resource; you can also pass a path to your own .elm file.