Love2D

Love2D reaches the browser through 2dengine's love.js player — a standalone player that runs .love files in the browser via an Emscripten build of LÖVE 11.5. No compile step: just package your game as a .love and drop the player's player.js, love.js, and love.wasm alongside.

Build for web

1. Download the 2dengine/love.js repo and extract it — call the extracted dir LOVEJS_DIST. It must contain player.js, style.css, 11.5/love.js, 11.5/love.wasm, and lua/normalize1.lua + lua/normalize2.lua.
2. Package your game as a .love (zip conf.lua, main.lua, and any other modules).
3. Copy player.js, style.css, the 11.5/ folder, and the lua/ folder alongside your .love and an index.html that loads player.js?g=your-game.love&v=11.5.

The example's build.sh does all this for you — see example-love2d/build.sh.

SDK integration

2dengine's love.js ships a JS-interop trick rather than a true FFI: Lua can synchronously evaluate JavaScript by calling os.execute("javascript:<code>"). Internally that hops love.system.openURL → window.open (intercepted by player.js) → eval. The result is written to window._output, which io.read() can read back via player.js's window.prompt override. normalize1.lua glues all of that together, so os.execute returns the evaluated string and no JS shim is needed.

-- wavedash.lua
local M = {}

function M.init()
  os.execute([[javascript:
    window.WavedashJS && window.WavedashJS.init({ debug: true })
  ]])
end

function M.update_load_progress(fraction)
  local clamped = math.max(0, math.min(1, fraction or 0))
  os.execute(string.format([[javascript:
    window.WavedashJS && window.WavedashJS.updateLoadProgressZeroToOne(%f)
  ]], clamped))
end

return M

Call it from the game

At the end of love.load:

local wavedash = require("wavedash")

function love.load()
  -- ...game setup...
  wavedash.update_load_progress(1)
  wavedash.init()
end

Adding more SDK methods

Embed the arguments directly into the JS literal — %q quotes strings safely for Lua-into-JS string contexts:

function M.submit_score(name, score)
  os.execute(string.format([[javascript:
    window.WavedashJS && window.WavedashJS.getLeaderboard(%q).then((lb) => {
      if (lb.success) window.WavedashJS.uploadLeaderboardScore(lb.data.id, %d, true);
    })
  ]], name, score))
end

Then call from Lua: wavedash.submit_score("level-1", 3500).

For methods that need to return data back to Lua, append a return to the JS string and read it with io.read():

function M.get_username()
  os.execute([[javascript:'return ' + (window.WavedashJS ? window.WavedashJS.getUsername() : '')]])
  return io.read() or ""
end

Async (Promise-returning) SDK methods are the ceiling of this approach — you'd need a JS-side dispatcher that resolves into window._output before Lua reads it.

wavedash.toml

game_id = "YOUR_GAME_ID_HERE"
upload_dir = "./build"