Orch8 Engine

Orch8 Engine is a self-hosted, durable workflow orchestration engine written in Rust that lets you define workflows as composable JSON sequences. It guarantees every step either completes, retries, or surfaces in a dead-letter queue, all from a single binary with one dependency: PostgreSQL (or SQLite for dev/embedded). It is designed as a lightweight alternative to multi-service orchestration stacks like Temporal or Airflow, trading ecosystem breadth for operational simplicity.

• Workflow Primitives — Supports Step, Parallel, Race, TryCatch, Loop, ForEach, Router, SubSequence, CancellationScope, and AB Split blocks for composable sequence design.
• Scheduling — Offers relative delays, business-days-only scheduling with holiday awareness, timezone-per-instance, jitter, send windows, and cron triggers with configurable tick intervals.
• Rate Limiting — Per-resource sliding window with deferred scheduling (not rejection), resource pools with weighted rotation, daily caps, and warmup ramps.
• Reliability — Crash recovery via state snapshots, configurable retry with exponential backoff, dead letter queue, idempotency keys, and circuit breakers with fallback handler routing and persistent state.
• Multi-tenancy — Tenant-scoped queries, per-tenant rate limits, per-tenant circuit breakers, tenant isolation middleware, and per-tenant noisy-neighbor protection.
• AI Agent Support — Unified llm_call handler covering OpenAI, Anthropic, Gemini, and 7+ more providers; dynamic step injection (self_modify), human-in-the-loop with timeout/escalation, and SSE streaming.
• Extensibility — External workers in any language via REST long-polling, gRPC sidecar plugins, WASM plugins, webhook events, workflow interceptors, and emit-event with deduplication.
• Observability — Prometheus metrics, structured JSON logging, audit log, execution tree visualization, and a Grafana dashboard template.
• Security — AES-256-GCM encryption at rest for context and credentials, OAuth2 credential refresh, API key authentication, and CORS configuration.
• Multi-language SDKs — TypeScript (authoring + worker), Python, and Go SDKs available; install via npm, pip, or go get respectively.
• Deployment Flexibility — Deploy via Docker, binary release, Homebrew, or Helm chart; managed cloud option available at cloud.orch8.io.