Connection config + the single source of truth for protocol/connection defaults.

There are two kinds of configuration:

1. Per-connection config — passed to Amarula.new/1

A map; you supply only what differs (at minimum :profile), merge/1 fills the rest from the defaults below.

| :storage | {Amarula.Storage.File, root: AMARULA_DATA_DIR || "./amarula_data"} | storage backend {module, opts} | | :retry_cache | ETS (see Amarula.RetryCache) | sent-message cache backend | | :registry | Amarula.ProfileRegistry (local) | {module, name} or bare name for the profile→connection registry; swap for Horde.Registry to enforce one-conn-per-profile cluster-wide (default: per node). See Amarula.ProfileRegistry | | :auth | loaded from storage | explicit creds (advanced; normally Amarula loads/persists these itself) | | :version | [2, 3000, 1035194821] | WhatsApp Web protocol version — MUST track src/Defaults/index.ts or the handshake is rejected. (Distinct from Baileys source parity — see Amarula.Baileys / docs/PARITY.md.) | | :browser | ["Mac OS", "Chrome", "14.4.1"] | browser triple [os, client, version] shown as the linked device. If the client (2nd element) contains "Android" (case-insensitive, e.g. ["MyApp", "Android", ""]), the connection registers as an Android client instead of WhatsApp Web — see the impact note below. | | :max_retries | 5 | reconnect attempts | | :retry_delay | 1000 | base reconnect backoff (ms) | | :connect_timeout_ms | 30_000 | WebSocket connect timeout | | :keep_alive_interval_ms | 30_000 | WA-level keep-alive ping interval | | :sender_idle_ms | 1_000 | how long a per-recipient ConversationSender stays warm after its last send before stopping. Larger = fewer respawns/session re-reads under bursty traffic (useful with a disk-backed store); smaller = sheds processes faster after a fan-out | | :sync_full_history | true | request full history on link | | :mark_online_on_connect | true | send presence-available on connect. false keeps this session unavailable — it appears offline to others and the primary phone keeps receiving push notifications (live messages are then queued offline rather than pushed to this session). | | :fire_init_queries | true | run the post-login init IQ queries | | :country_code | "US" | | | :headers / :origin / :agent | see defaults | HTTP/WS handshake |

Amarula.new(%{profile: :me, sync_full_history: false}) |> Amarula.connect()

Android browser mode (impact)

Setting an Android :browser (e.g. ["MyApp", "Android", ""]) registers the linked device as an Android client rather than WhatsApp Web. This changes the registration/login payload in three ways (mirroring Baileys #2201):

• ClientPayload.userAgent.platform becomes :ANDROID (not :WEB).
• webInfo is omitted (it's a web-client field).
• DeviceProps.platformType becomes :ANDROID_PHONE.

Why you'd opt in: an Android-registered session can receive view-once media that a Web session cannot.

Costs / caveats — opt in deliberately:

• Experimental. This is a newer, less-exercised WhatsApp path; upstream labels it experimental ("use at your own risk"). It may behave unexpectedly or be tightened by WhatsApp.
• The device shows as a phone/Android client, not a desktop browser, in the user's "Linked devices" list.
• Default (any non-Android :browser) is unchanged — full Web behaviour, webInfo sent, platform: :WEB. Existing configs are unaffected.

2. App-global config — config :amarula, ...

Only the pluggable seams (apply to every connection that doesn't override them):

config :amarula, :default_storage_adapter, Amarula.Storage.File
config :amarula, :retry_cache_adapter, Amarula.RetryCache.ETS

Logging

Amarula logs through Elixir's Logger. Almost everything is :debug; only connection lifecycle, pairing, and errors are :info/:warning/:error. To keep your dev console clean, set the global level — or silence Amarula specifically without affecting your own logs:

# your app's config
config :logger, level: :info

# or, mute just Amarula (Elixir 1.13+):
Logger.put_module_level(Amarula.Connection, :warning)

Telemetry (Amarula.Telemetry) is the structured, log-independent way to observe Amarula in production.