Key, bridge, phone. Then a message.
Run these in order. Your first bridge is free for 7 days with a card on file, nothing charged until the trial ends.
Create an API key at Dashboard → API keys. It starts with sk_ and is shown once, so copy it now. Every call below sends it as Authorization: Bearer $WA_API_KEY.
customer_ref = sandbox. Skip steps 2 and 3, use sandbox wherever a customer_ref appears below, and send to 15550001234, a fake contact who replies within seconds. Events show on your dashboard.cargo add reqwest --features blocking,json && cargo add serde_json
export WA_API_KEY="sk_..."
Your first bridge is created from the dashboard: one click connects a number and starts the 7-day free trial (card on file, $0 today). Every API call below can address it as /api/instances/default/…: default always means your first bridge, so no name goes in the URL. The call here is how you add more bridges to the subscription.
customer_ref is your internal identifier (user ID, slug, anything you control). webhook_url is optional: leave it out to use the hosted inbox and read events on the dashboard, change it any time with PATCH.
Store the webhook_secret that comes back. It signs every webhook the bridge sends you.
402 no_subscription: connect a number in the dashboard first.use reqwest::blocking::Client;
use serde_json::{json, Value};
use std::env;
fn main() -> Result<(), Box<dyn std::error::Error>> {
let api_key = env::var("WA_API_KEY")?;
let client = Client::new();
let bridge: Value = client
.post("https://wabridges.com/api/instances")
.bearer_auth(&api_key)
.json(&json!({
"customer_ref": "user-123",
"webhook_url": "https://yourbackend.com/hook",
}))
.send()?
.json()?;
println!("{}", bridge);
Ok(())
}
{"id": "7d09aa9c-…", "customer_ref": "user-123", "state": "running", "created_at": 1777180605, "webhook_secret": "whs_…", "webhook_url": "https://…/hook"}
You need the phone in hand for this step. Request a pairing code, open WhatsApp on the phone, go to Linked Devices → Link a device → Link with phone number, then enter the code. Any number works, personal, VoIP, or a spare SIM. No phone? Use sandbox.
Once paired, the bridge fires a connected webhook event. Poll /proxy/status or wait for the event.
let result: Value = client
.post("https://wabridges.com/api/instances/user-123/proxy/pair")
.bearer_auth(&api_key)
.json(&json!({ "phone": "15550001234" }))
.send()?
.json()?;
println!("Enter this code on the phone: {}", result["code"]);
{"code": "ABCD-EFGH"}
Add an Idempotency-Key: <unique-per-message> header in production so a timeout plus retry can never double-send. See Idempotency.
A bridge that sat for a few hours with no phone linked is paused to save resources. The first call after that returns 503 bridge_starting with a Retry-After header. Wait those seconds and retry once.
let msg: Value = client
.post("https://wabridges.com/api/instances/user-123/proxy/send/text")
.bearer_auth(&api_key)
.json(&json!({ "chat": "15559876543", "body": "Hello from the API!" }))
.send()?
.json()?;
println!("{}", msg["message_id"]);
{"message_id": "ACE41E...", "timestamp": 1777180605}
Inbound messages and events are delivered by POST to your webhook_url. Return 200 immediately and do the work afterwards.
The webhook guide has every event type and field, plus signature verification.
// Cargo.toml: cargo add axum tokio --features tokio/full && cargo add serde_json
use axum::{extract::Json, routing::post, Router};
use serde_json::Value;
async fn hook(Json(payload): Json<Value>) -> &'static str {
if payload["event"] == "message" && payload["from_me"] != true {
println!("{}: {}", payload["name"], payload["body"]);
}
""
}
#[tokio::main]
async fn main() {
let app = Router::new().route("/hook", post(hook));
let listener = tokio::net::TcpListener::bind("0.0.0.0:3000").await.unwrap();
axum::serve(listener, app).await.unwrap();
}
Next
Everything the quickstart skipped: media, polls, contacts, presence, and every webhook payload.