Webhooks, cron schedules, and app events trigger chains of nodes that fetch, transform, and route data: n8n is a workflow automation platform built around a visual, node-based editor. It ships with 400+ built-in integrations covering databases like Postgres, SaaS tools like Slack and HubSpot, and every major AI provider. When a pre-built node does not exist, the HTTP Request node calls any REST API, and the Code node runs JavaScript or Python inline, so you are never blocked by a missing connector. Workflows execute as directed graphs with branching, loops, error handling, and sub-workflows, and every run is logged for inspection and replay during debugging. It also includes LangChain-based nodes for building AI agents with tool calling and memory. Self-hosting on RepoCloud gives you unlimited workflow executions with no per-task pricing, and all data stays on your instance. Runs on Node.js with SQLite by default; add Postgres and Redis queue mode when you need to scale workers horizontally.

Every email your app sends while you build and test it lands in OwlMail's browser inbox instead of a customer's mailbox. Point any application's SMTP settings at OwlMail and every message is ready to open as rendered HTML, plain text, headers, or raw source. Attachments and inline images sit beside the body, and seven preset preview widths show how the message lays out on phones, tablets, and desktops before anyone real sees it. A Verify panel checks subject, body, and link hosts against expectations, while CI pipelines use the REST API with delivery cursors to wait for exactly the messages their test run produced, assert on them, and clean up afterwards. Coding agents get the same inbox read-only over MCP, so an assistant can confirm a signup email arrived without touching your mail server. When a message proves itself, relay it onwards to a real SMTP server, by hand or automatically under filtering rules, or fire webhooks with HMAC signatures and retry queues into the rest of your automation. Everything stores as plain .eml files on disk, with optional SQLite indexing, S3 attachment storage, and ZIP exports for archiving. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Automatisch runs your Zapier workflows on your own hardware - an open-source, self-hosted automation platform built as a direct alternative. Flows are chains of steps: one trigger (a polling or webhook event such as a new GitHub issue, a Stripe payment, or a form submission) followed by action steps that pass data downstream (post to Slack, append a Google Sheets row, update Notion). The visual builder deliberately mirrors Zapier's trigger-action model, so migrating existing Zaps requires no retraining and no programming knowledge. Roughly 60 integrations cover common business services - Slack, GitHub, Google Sheets, Notion, Stripe, Discord - and connections store credentials per service, with multiple accounts per app supported. Every execution runs on your own server: execution history, logs, and payload data never touch a third-party processor, which matters for GDPR, healthcare, and finance workloads. Error handling with retry logic, a REST API for programmatic flow management, and Docker Compose deployment round out the platform. The AGPL-3.0 Community Edition has no feature limits or per-task billing; an Enterprise Edition adds SSO, roles, and audit logs.

The integrations your SaaS product offers its own users - that is what Nango, an open-source product-integrations platform, exists to build. It solves the repetitive infrastructure work behind every third-party API connection: OAuth flows, API key handling, token refresh, encrypted credential storage, rate-limit backoff, retries, and multi-tenant connection management. It ships pre-built auth configurations for 800+ APIs. Your users connect their accounts through an embeddable, white-label Connect UI, and your backend then reads or writes data through Nango's proxy, SDKs, or REST API without ever touching raw credentials. Integration logic is written as TypeScript functions covering actions, scheduled data syncs, and webhook processing - all running on one runtime with retries, checkpointing, and per-connection logs built in. Syncs pull records incrementally on a schedule, one-way or two-way, which suits RAG pipelines, search indexing, and keeping local copies of external data current. Selected actions can also be exposed as tool schemas or through a built-in MCP server, so AI agents operate on user-connected accounts without ever handling provider credentials. Auth support spans OAuth 2.0, OAuth 1.0a, API keys, basic auth, and JWT, and observability - logs, metrics, failure detection, and a reconnect flow for expired credentials - is scoped per customer connection for easier support debugging. Works with any backend language. Self-hosting on RepoCloud keeps all customer credentials and synced data on infrastructure you control, which matters for data residency and compliance requirements.

TextBee turns an Android phone with a SIM card into an SMS gateway your applications can call, so one-time codes, alerts, reminders, and two-way conversations go out as ordinary texts from a real number. Pair a phone by scanning a QR code in the dashboard, then send messages from the REST API, the dashboard, or the JavaScript SDK. Bulk campaigns load from a CSV file and are paced to stay within carrier limits, and any message can be scheduled up to 72 hours ahead. With several phones or SIM cards attached, each message can name the device and SIM it should use. Every message moves through pending, dispatched, sent, delivered, or failed, and the history view lists all devices together. Incoming texts appear in the dashboard and the API, and webhooks push received messages and delivery reports to your server with an HMAC-SHA256 signature you can verify. An official MCP server lets AI assistants send texts and read replies. API keys, devices, usage, and webhook subscriptions are all managed from one web interface. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. MIT licensed.

Convoy is an enterprise-grade webhooks gateway that manages both incoming and outgoing webhook traffic to guarantee reliable event delivery without exposing internal microservices to the public internet. Organizations deploy the platform at the edge to ingest events from message brokers such as Apache Kafka, RabbitMQ, and Google Cloud PubSub, or receive HTTP webhooks from third-party services directly. The gateway enforces delivery policies through configurable rate limiting per endpoint, circuit breaking during downstream outages, and automated retries using constant or exponential backoff with jitter. Developers can generate customer-facing webhook portals embedded via iframes, allowing end users to inspect delivery attempts, verify HMAC-SHA256 signatures, and manually replay failed events. Comprehensive security controls include static egress IP proxying to prevent server-side request forgery, automated rolling secret keys, and instant alerting via Slack or email when endpoints fail consecutively. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Elastic License 2.0 licensed.

Rustunnel turns a service running on your laptop or private network into a public HTTPS, TCP, or UDP endpoint without opening inbound ports on the machine where it lives. Point the client at a local port and share the public address for webhook testing, a quick demo, an AI agent tool, SSH access, a game server, or an IoT device that cannot accept inbound connections. Give tunnels custom subdomains on your own wildcard domain, terminate HTTPS with automatic Let's Encrypt certificates, and keep client traffic encrypted from edge to local service. Put several backends behind one subdomain or TCP port and let TCP or HTTP health probes remove sick members before visitors hit them. When two peers can reach each other directly, start a P2P tunnel with NAT hole punching and QUIC, with relay fallback when the direct path fails. Watch sessions, tunnel health, traffic, and request logs from the live dashboard, inspect headers and bodies in the local request inspector, and replay a captured call while debugging a webhook. Manage tunnels, tokens, groups, captured requests, and history through the REST API, scrape Prometheus metrics, review audit logs, or let an MCP-compatible coding assistant create and close tunnels in plain language. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. AGPL-3.0 licensed.