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.

With over 5,000 GitHub stars since its June 2026 launch, OOMOL OpenConnector bridges the gap between AI agents and the real world by handling the authentication nightmare that stops LLMs from calling external APIs safely. The runtime connects to more than 1,000 SaaS providers — GitHub, Gmail, Notion, Slack, Microsoft, HubSpot, Google Workspace, and hundreds more — through 10,000+ prebuilt typed Actions that agents can discover and execute without ever touching raw credentials. OAuth2 flows, API key rotation, custom credentials, and no-auth providers are all managed centrally with AES-encrypted storage, scoped runtime tokens, and configurable action allowlists and blocklists that enforce least-privilege access. Agents interact through five access surfaces: the Model Context Protocol endpoint at /mcp for Claude and other MCP-capable hosts, a full REST API at /v1 for programmatic control, an auto-generated OpenAPI specification for code generation, a TypeScript SDK for application integration, and the oo CLI for local agent relay. The built-in Web Console provides browser-based administration for configuring OAuth apps, managing connections, inspecting action schemas, and reviewing execution logs with redacted inputs. Deploy via Docker Compose with SQLite for single-server setups, run from source on Node.js 22+, or push to Cloudflare Workers with D1 and R2 for edge deployment. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

With 13,800+ GitHub stars and active releases through 2026, Casdoor is the open-source identity platform that ships OAuth 2.0, OIDC, SAML 2.0, CAS, LDAP, SCIM 2.0, WebAuthn passkeys, TOTP multi-factor authentication, and Face ID biometric login in a single Go binary with a React web console — covering every authentication protocol your organization will ever need. Social login connects 50+ identity providers including Google, GitHub, Microsoft Azure AD, Facebook, WeChat, DingTalk, Apple, Twitter, and LinkedIn without custom code. The AI-first architecture includes a Model Context Protocol gateway for AI agent authentication and Agent-to-Agent protocol support for securing LLM-powered workflows. Built-in Casbin integration delivers authorization primitives beyond basic RBAC: attribute-based access control, relationship-based access control, and custom policy models through a unified engine. The organization-scoped multi-tenancy model isolates users, applications, and identity providers per tenant with customizable login pages, branding, and SMTP configuration. SCIM 2.0 endpoints automate user provisioning from HR systems and Active Directory. Official SDKs for Go, Java, Node.js, Python, and PHP accelerate application integration. The RESTful API exposes every resource for programmatic management. Comprehensive audit logs record authentication events and administrative actions. Deploy via Docker Compose with MySQL or PostgreSQL, the all-in-one SQLite Docker image for quick trials, or the official Kubernetes Helm chart for production clusters. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.

Ory Hydra is an OpenID Certified OAuth 2.0 and OpenID Connect provider that plugs into any existing user database or authentication system through a headless consent and login bridge, letting you own your authorization infrastructure without rebuilding identity management from scratch. The Go binary ships at under 15MB with zero system dependencies and exposes two distinct API surfaces: a public endpoint on port 4444 handling authorization code flows, token exchanges, PKCE challenges, device authorization grants per RFC 8628, and OpenID Connect discovery, plus an admin endpoint on port 4445 managing client registration, token introspection, consent session lifecycle, and JWKS rotation. Access tokens can be issued as opaque reference tokens or signed JWTs for stateless validation at resource servers, while refresh token rotation, token revocation per RFC 7009, and pairwise subject identifiers provide granular security controls. Persistent storage spans PostgreSQL, MySQL, and CockroachDB with automatic schema migrations, and the architecture supports horizontal scaling behind load balancers with shared database state. Dynamic client registration per RFC 7591 enables automated provisioning, and the OAuth 2.0 Threat Model security considerations are implemented as default behaviors rather than optional add-ons. Trusted by OpenAI and other internet-scale platforms. Helm charts and Docker Compose quickstarts provide production-ready deployment paths alongside the broader Ory ecosystem including Kratos for identity management, Oathkeeper for zero-trust API proxying, and Keto for fine-grained permissions. Running on a dedicated VPS on RepoCloud with guaranteed CPU, RAM, and SSD, full root SSH access, and a browser serial console. Apache 2.0 licensed.