Connectors

A connector puts external systems on the bus. There are three shapes, by escalating need (ADR-0007/0011):

1. A manifest on a built-in driver — most SaaS is this: a .vjs file with driver "http-poll" (or oauth-poll, http-out, http-in, mqtt-in/out, timer, slack-out…) and UPPERCASE config. No code. The driver catalog with each config contract: GET /drivers or the vejas_drivers MCP tool.
2. An exec bridge — exec-source / exec-sink / exec-stream-source / rpc:exec run a child program in any language over stdio. Kafka rides this (kcat carries the full librdkafka auth matrix); the generic offset-resume (OFFSET_KV) gives publish-before-commit resume in our KV, kill -9-proof (CI-tested).
3. A first-class standalone binary — when the ordering that guarantees no-loss must live in one process with its own bus client: IBM MQ (MQGET-under-syncpoint → bus pub-ack → MQCMIT) and AMQP/RabbitMQ (consume→pub-ack→ack; publish→confirm→ack). Configured by env, not by manifest. See Brokers.

Whatever the shape, the same rules hold: subjects under vx., at-least-once with the ack after the side effect, credentials through secret() or the deployment’s secret machinery — never a literal (a CI lint enforces it on every certified recipe), and an admission test that proves data actually flows (the certified catalog).