Listening

app:listen hands the socket to the Rust core and blocks the Lua thread.

app:listen(3000)   -- blocks; defaults to 3000 when omitted

app:listen(3000, function()   -- callback runs once the port is bound,
    print("Ready!")           -- before any request is served
end)

Startup logging

Ludi prints nothing on startup — logging is the application’s choice, in the callback:

app:listen(3000, function()
    print("Listening on http://localhost:3000")
end)

Errors

Caution

A port that cannot be bound (already in use, no permission) raises a regular Lua error.

local ok, err = pcall(function()
    app:listen(80)
end)
if not ok then
    print("failed to bind: " .. err)
end