Gatus

# MISSION: Scaffold "Gatus" Production Architecture
You are an expert Senior Staff Software Architect and Full-Stack Engineer. Your mission is to scaffold and implement a production-grade, highly reliable, and modular codebase following the proven architecture of **Gatus**.
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## 1. PROJECT SPECIFICATIONS & BENCHMARK
- **Reference Architecture**: Gatus
- **What It Does**: Gatus is a self-hosted, developer-oriented health dashboard that runs configurable HTTP, ICMP, TCP, DNS, gRPC and other checks against services and turns failing conditions into Slack, PagerDuty and other alerts.
- **Domain & Category**: Automated Health Dashboard & Status Monitor
- **Production Scale**: solo
- **Development Mode**: CLASSIC
- **Architectural Rationale**: The whole product ships as one Go binary with the Vue dashboard embedded via go:embed and YAML-defined check conditions, so a status page needs no separate frontend server and, by default, no external database.
- **Live Website Reference**: https://gatus.io
- **Source Repository**: https://github.com/TwiN/gatus
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## 2. PRODUCTION TECH STACK
- **Full Stack Array**: Go, Vue, Fiber, SQLite, PostgreSQL, Chart.js, Tailwind CSS, Prometheus, Docker
- **Primary Language(s)**: Go, Vue
- **License of the reference repo**: Apache-2.0
- **Frontend**: Vue — Vue 3 dashboard (web/app) built with vue-cli-service; the compiled bundle is embedded into the Go binary.; Chart.js — Response-time and uptime graphs via vue-chartjs, chartjs-adapter-date-fns and chartjs-plugin-annotation.; Tailwind CSS — Utility CSS for the dashboard, composed with class-variance-authority and tailwind-merge for shadcn-style variants.
- **Backend & APIs**: Go — The entire server, health-check engine and alerting logic is a single Go module (main.go, go.mod requires go1.26).; Fiber — HTTP framework (gofiber/fiber/v2, backed by valyala/fasthttp) serving the API and the embedded dashboard.; Prometheus — Exposes check results as Prometheus metrics via prometheus/client_golang.
- **Data & persistence**: SQLite — Default storage backend for endpoint status history (modernc.org/sqlite, pure-Go driver, no CGO).; PostgreSQL — Alternative storage backend for status history via lib/pq, documented for multi-replica setups.
- **Infrastructure & deploy**: Docker — Multi-stage build: golang:alpine compiles the binary, then a scratch image runs it with the frontend baked in.; GitHub Actions — test.yml, test-ui.yml, benchmark.yml and four publish-*.yml workflows build and push images per branch/tag.
- **Tooling, testing & ops**: Go testing — Unit tests and benchmarks live alongside every package (api/*_test.go, jsonpath/jsonpath_bench_test.go).
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## 3. KEY ARCHITECTURAL DECISIONS (audited from https://github.com/TwiN/gatus @ 7f3873d)
1. **Single Go binary embeds the entire Vue frontend**: web/static.go serves the vue-cli-service build output from inside the Go binary, so a Gatus deployment is one executable plus a YAML config file; the Makefile frontend-build target compiles web/app before the Go build runs.
2. **Endpoint checks are configuration, not code**: config/endpoint, config/suite and config/connectivity define a YAML schema (config.yaml) where each check is a list of string conditions like "[STATUS] == 200"; jsonpath/jsonpath.go and pattern/pattern.go implement the condition language without an external expression engine.
3. **Fiber over the standard library net/http**: api/api.go builds on gofiber/fiber/v2 (valyala/fasthttp underneath) rather than net/http, trading some standard-library compatibility for lower overhead on the badge and chart endpoints that render per-request.
4. **Storage is pluggable but defaults to embedded SQLite**: storage/config.go and storage/store select between SQLite (modernc.org/sqlite, no CGO required) and PostgreSQL (lib/pq); the .examples directory ships a docker-compose file for each, plus one for sharing state across multiple remote instances.
5. **Alerting providers are a plugin-style package, not a webhook wrapper**: alerting/provider implements native clients for over 30 destinations (Slack, PagerDuty, Discord, Twilio, Teams, AWS SES via aws-sdk-go-v2, Gitea via code.gitea.io/sdk/gitea, and a generic custom provider), so watchdog/alerting.go can dispatch structured alerts without shelling out to curl.
6. **Author-maintained micro-libraries replace common third-party deps**: go.mod pulls in TwiN/gocache, TwiN/health, TwiN/logr, TwiN/whois and TwiN/deepmerge — small single-purpose packages by the same maintainer (TwiN) instead of heavier general-purpose alternatives, keeping the dependency tree narrow for a project shipped as a single static binary.
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## 4. NON-NEGOTIABLE ARCHITECTURAL GUARDRAILS
1. **Monorepo & Modular Separation**:
   - Structure as a Turborepo monorepo with strict package boundaries:
     - `apps/web`: Application UI, routing, layouts, and server endpoints.
     - `packages/ui`: Shared design tokens, CSS variables, and Radix UI primitive components.
     - `packages/db`: Database schemas, client singleton, declarative migrations, and seed scripts.
     - `packages/config`: Shared TypeScript, ESLint, and build configurations.
2. **Strict Type Safety & Zero `any` Policy**:
   - Enable `strict: true`, `noImplicitAny: true`, and `strictNullChecks: true`.
   - Validate ALL external inputs, API request bodies, and query parameters with **Zod** schemas before execution.
3. **Frontend & Rendering Guidelines**:
   - Isolate interactive UI state to leaf components. Keep core pages lightweight and performant.
4. **Design System & Aesthetics**:
   - Keep every color, radius, shadow and font in a single token file (CSS variables) and consume tokens everywhere; never hardcode hex values in components.
   - Prefer crisp 1px borders and one subtle shadow scale over blurry default shadows. Pair one sans-serif for body/headings with one monospace for tags, badges, metrics, and code.
5. **Data Layer & Reliability**:
   - Write declarative schema definitions with foreign keys, composite indexes on queried filters, and automated timestamp triggers.
   - Use connection pooling and prepared statements for serverless database execution.
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## 5. STEP-BY-STEP SCAFFOLDING ROADMAP
- **Phase 1: Workspace & Root Config**: Initialize package manager, monorepo configuration (`turbo.json`, `tsconfig.base.json`, `package.json`).
- **Phase 2: Database Schema & Client**: Set up the data layer (SQLite, PostgreSQL): client, connection pool, models, and migration scripts.
- **Phase 3: Design Tokens & UI Primitives**: Build accessible `Button`, `Input`, `Card`, `Badge`, and layout wrappers inside `packages/ui`.
- **Phase 4: Core Application Routes & Handlers**: Implement primary authentication, user session handling, and application routes.
- **Phase 5: Quality Assurance & Build Verification**: Run `tsc --noEmit`, ESLint, Prettier, and smoke test suites to ensure zero compilation or runtime errors.
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## 6. EXECUTION INSTRUCTIONS
1. Review all specifications, architectural guardrails, and stack choices above.
2. Present the full monorepo directory tree structure.
3. Systematically generate the complete, production-ready codebase according to the 5-phase roadmap above — starting with the root workspace setup, followed by the database schema, UI design system package, and full-stack application routes until the repository is fully scaffolded and ready to run.