System Architecture

%%{init: { "theme": "base", "themeVariables": { "background": "#0f0f0f", "primaryColor": "#161616", "primaryTextColor": "#e0e0e0", "primaryBorderColor": "#3a3a3a", "lineColor": "#555555", "secondaryColor": "#111111", "tertiaryColor": "#0f0f0f", "clusterBkg": "#0d0d0d", "clusterBorder": "#2a2a2a", "titleColor": "#888888", "edgeLabelBackground": "#0f0f0f", "fontFamily": "DM Mono, monospace", "fontSize": "13px", "nodeBorder": "#3a3a3a", "mainBkg": "#141414" } }}%% graph TB subgraph EXT[" ☎ EXTERNAL"] PAT["☎ Patient\nPhone call"] VAPI["◈ Vapi Platform\nVoice AI · Webhooks"] end subgraph APP[" ⚡ APPLICATION LAYER"] CADDY["⟳ Caddy\n:80 · :443 TLS Proxy"] FAPI["⚡ FastAPI\n:8000 Webhook · API"] GEM["✦ Google Gemini\nLLM intent summary"] end subgraph DATA[" ▣ DATA LAYER"] PG[("▣ PostgreSQL\n:5432\nCalls · Events\nIdempotency")] RDS[("⟳ Redis\n:6379\nJob queue")] end subgraph WORK[" ⚙ WORKER"] ARQ["⚙ arq Worker\nRetry · Callbacks\nOutbound call"] end subgraph OBS[" ◉ OBSERVABILITY"] REXP["redis-exporter\n:9121"] PROM["Prometheus\n:9090"] GRAF["Grafana\n:3000"] MON["Monitor UI\n/monitor"] end subgraph INFRA[" ⬆ CI/CD & INFRASTRUCTURE"] GHA["GitHub Actions\nTest → Build → Deploy"] GHCR["GHCR\nDocker Registry"] TF["Terraform\nStaging VPS"] R2["R2\nCloudflare R2 backups"] end %% ── Core request path ────────────────────────────────────── PAT -->|"voice stream"| VAPI VAPI -->|"HTTPS webhook\ntool-calls · events"| CADDY CADDY -->|"HTTP :8000"| FAPI FAPI -->|"asyncpg\nSQL write"| PG FAPI -->|"enqueue\nfailed job"| RDS FAPI <-->|"summarise\nintent"| GEM %% ── Worker path ───────────────────────────────────────────── RDS -->|"poll queue"| ARQ ARQ -.->|"poll /healthz\nevery 5s"| FAPI ARQ -.->|"outbound call\non recovery"| VAPI %% ── Observability scraping ────────────────────────────────── REXP -->|"scrape\nredis metrics"| RDS PROM -->|"scrape /metrics"| FAPI PROM -->|"scrape :9121"| REXP GRAF -->|"PromQL queries"| PROM MON -.->|"GET /api/monitor/stats\nevery 5s"| FAPI %% ── Infra flows ───────────────────────────────────────────── PG -.->|"pg_dump\nscheduled"| R2 GHA -->|"push image"| GHCR GHA -->|"SSH deploy\ndocker compose pull"| FAPI GHA -->|"terraform apply"| TF %% ── Styles ────────────────────────────────────────────────── classDef core fill:#141414,stroke:#4a4a4a,stroke-width:1.5px,color:#f0f0f0 classDef data fill:#111,stroke:#333,stroke-width:1px,color:#d0d0d0 classDef worker fill:#111,stroke:#2e2e2e,stroke-width:1px,color:#c0c0c0 classDef obs fill:#0e0e0e,stroke:#252525,stroke-width:1px,color:#aaa classDef infra fill:#0d0d0d,stroke:#222,stroke-width:1px,color:#888 classDef ext fill:#111,stroke:#3a3a3a,stroke-width:1.5px,color:#e0e0e0 class FAPI,CADDY core class PAT,VAPI ext class GEM worker class PG,RDS data class ARQ worker class REXP,PROM,GRAF,MON obs class GHA,GHCR,TF,S3 infra