npx skills add ...
npx skills add iii-hq/iii --skill iii-architecture-patterns
Use when composing iii primitives into backend architectures: durable workflows, reactive backends, agentic pipelines, event-driven CQRS, effect pipelines, and trigger-transform-action automation.
npx skills add iii-hq/iii --skill iii-architecture-patterns
Use this skill when the task is larger than one function or trigger. Pick the pattern from the
requirement, then implement it with Function, Trigger, Worker, state, queues, streams, and
pub/sub.
| Requirement | Pattern | iii shape |
|---|---|---|
| Sequential work with retries, DLQ, step tracking | Durable workflow | Functions chained through named queues, progress in state |
| Keep views, metrics, cache, or clients in sync | Reactive backend | State triggers plus stream/pubsub side effects |
| Specialized AI agents hand work to each other | Agentic backend | One function per agent, queue handoffs, shared state |
| Commands publish events and projections update independently | Event-driven CQRS | Command functions, event log in state, subscribe triggers |
| Pure, traceable composition | Effect pipeline | Small functions composed synchronously with trigger() |
| Webhook/cron automation chains | Low-code automation | Trigger, transform, action nodes chained by enqueue |
Use named queues when steps need different retry, FIFO, or concurrency policy.
Use state triggers when the requirement says "after create/update, do this", "avoid polling", or "push live updates".
Model each agent as a function with one responsibility. Store shared context in state and hand off work through named queues.
Commands validate and publish domain events. Projections subscribe independently and write query-optimized state.
iii-core-primitives.iii-engine-config.iii-sdk-reference.from iii import register_worker
iii = register_worker("ws://localhost:49134")
def track(order_id, step, status):
iii.trigger({
"function_id": "state::update",
"payload": {
"scope": "orders",
"key": order_id,
"ops": [{"op": "set", "path": f"/steps/{step}", "value": status}],
},
})
def validate(order):
track(order["id"], "validate", "done")
return iii.trigger({
"function_id": "orders::charge",
"payload": order,
"action": {"type": "enqueue", "queue": "order-payment"},
})
iii.register_function("orders::validate", validate)use iii_sdk::TriggerAction;
use iii_sdk::protocol::TriggerRequest;
use serde_json::json;
async fn enqueue_charge(iii: iii_sdk::IIIClient, order: serde_json::Value) -> Result<serde_json::Value, iii_sdk::Error> {
iii.trigger(TriggerRequest {
function_id: "state::update".into(),
payload: json!({
"scope": "orders",
"key": order["id"],
"ops": [{ "op": "set", "path": "/steps/validate", "value": "done" }]
}),
action: None,
timeout_ms: None,
}).await?;
iii.trigger(TriggerRequest {
function_id: "orders::charge".into(),
payload: order,
action: Some(TriggerAction::Enqueue { queue: "order-payment".into() }),
timeout_ms: None,
}).await
}iii.registerFunction("todos::on-change", async (event) => {
await iii.trigger({
function_id: "stream::send",
payload: { stream_name: "todos-live", group_id: "default", data: event.new_value },
action: TriggerAction.Void(),
});
});
iii.registerTrigger({
type: "state",
function_id: "todos::on-change",
config: { scope: "todos" },
});iii.registerFunction("agents::researcher", async (task) => {
await iii.trigger({
function_id: "state::set",
payload: { scope: "research", key: task.id, value: { findings: [] } },
});
return iii.trigger({
function_id: "agents::critic",
payload: task,
action: TriggerAction.Enqueue({ queue: "agent-tasks" }),
});
});iii.registerFunction("cmd::add-inventory-item", async (input) => {
const event = { type: "inventory.item-added", itemId: input.itemId, quantity: input.quantity };
await iii.trigger({
function_id: "state::set",
payload: { scope: "inventory-events", key: `${Date.now()}-${input.itemId}`, value: event },
});
await iii.trigger({ function_id: "publish", payload: { topic: event.type, data: event } });
return { accepted: true };
});
iii.registerTrigger({
type: "subscribe",
function_id: "proj::inventory-list",
config: { topic: "inventory.item-added" },
});