REI3

REI3 is a self‑hosted, low‑code platform that transforms spreadsheet‑based workflows into robust multi‑user applications. From a developer’s perspective, the core value lies in its open architecture and extensibility: you can author data models, forms, workflows, and integrations entirely through declarative YAML/JSON files or a visual designer, while still having full control over the underlying services. The platform exposes a REST API for CRUD operations, workflow triggers, and event hooks, making it straightforward to embed REI3 logic into existing micro‑services or SaaS stacks.

Architecture

• Language & Runtime: REI3 is written in Go (1.20+), leveraging the language’s strong type system, concurrency primitives, and static binaries for minimal runtime overhead.
• Web Stack: The frontend is a single‑page React application served by an embedded HTTP server. It communicates with the backend via WebSocket for real‑time updates and REST for CRUD operations.
• Persistence: Data is stored in a PostgreSQL database (v14+). The schema is generated from the platform’s model definitions, and migrations are handled automatically by a built‑in tool.
• Search & Indexing: Full‑text search is powered by PostgreSQL’s native tsvector capabilities, with optional integration to ElasticSearch for advanced use cases.
• Security: Role‑based access control (RBAC) and record‑level policies are defined in YAML. End‑to‑end encryption is supported through an optional key‑management service, with AES‑256 keys stored in a dedicated vault.

Core Capabilities

• Low‑Code Data Modeling: Define tables, fields, relations, and validation rules in declarative files; the platform auto‑generates CRUD APIs and UI components.
• Workflow Engine: Conditional forms, state machines, scheduled jobs, PDF export, and email/Slack notifications are all configurable without writing code.
• Integration Layer: Expose REST endpoints, consume external APIs, import/export CSV/ICS, and publish events to webhooks or message queues (Kafka/RabbitMQ).
• Extensibility: Plugins can be written in Go or Node.js and registered via a simple manifest. The plugin system allows custom field types, business logic, or UI widgets.

Deployment & Infrastructure

REI3 ships as a single static binary (Linux x64/arm64, Windows) or a Docker image (r3team/r3:latest). For production use:

• Containerization: Docker Compose or Kubernetes manifests are provided; the platform supports horizontal scaling of the API layer behind a load balancer.
• Stateful Storage: PostgreSQL can run as a separate container or an external managed database. The platform includes health checks and graceful shutdown hooks.
• Observability: Prometheus metrics, structured JSON logs, and optional OpenTelemetry support enable seamless monitoring in modern cloud environments.

Integration & Extensibility

• APIs: The auto‑generated REST API follows a consistent pattern (/api/v1/<model>/<id>) and supports OData‑style filtering, pagination, and sorting.
• Webhooks: Trigger external services on create/update/delete events; payloads can be customized via templates.
• Custom Plugins: Developers can ship binary plugins that expose new endpoints or UI components; the platform loads them at startup, allowing rapid feature iteration.
• Scripting: Embedded Lua/JavaScript engines enable on‑the‑fly business rules without recompilation.

Developer Experience

• Configuration: All platform settings (database, email, auth providers) are managed via environment variables or a single config.yaml.
• Documentation: The official docs provide a comprehensive API reference, plugin guide, and migration tutorials.
• Community: Active GitHub discussions, a Discord channel, and an issue tracker ensure quick feedback loops.
• Licensing: MIT‑style license allows commercial use without royalties, encouraging adoption in enterprise environments.

Use Cases

1. Internal SaaS – Quickly spin up a customer‑facing application (e.g., time tracking, ticketing) with minimal backend code.
2. Data‑centric Ops – Replace legacy spreadsheets with a secure, searchable database that supports role‑based access and audit trails.
3. Integration Hub – Use REI3 as a glue layer between disparate systems, exposing unified APIs while orchestrating workflows.
4. MVP Development – Prototype business logic in the visual designer, then export the model to a production database and deploy with zero code.

Advantages

• Performance: Go’s compiled binaries deliver low latency, and PostgreSQL provides robust ACID guarantees.
• Flexibility: Declarative models mean changes are versioned and reversible; the plugin system allows native extensions.
• Ownership: Self‑hosted by design, giving developers full control over data residency and compliance.
• Cost: Free for all use cases; no hidden fees or subscription locks, unlike many commercial low‑code platforms.

In summary, REI3 offers a lightweight yet powerful stack for developers who need to replace spreadsheets with secure, multi‑user applications while maintaining full control over the codebase and infrastructure.