CUB-135: resolve merge conflict with dev + lint fixes

- Merge SSEProvider/ToastContainer with Dashboard/Inventory routes
- Fix no-explicit-any in useSSE.ts (Record<string, unknown>)
- Fix exhaustive-deps warning in InventoryPage (wrap filaments in useMemo)

deploy.sh

@@ -1,37 +1,34 @@
 #!/bin/bash
 set -e
 
-echo "🔧 Deploying Extrudex (Go + React) on Raspberry Pi..."
+echo "🔧 Deploying Extrudex Docker runtime..."
 
 # Check if Docker Compose is available
-if ! docker compose version &>/dev/null && ! command -v docker-compose &>/dev/null; then
+if ! command -v docker-compose &> /dev/null && ! docker compose version &> /dev/null; then
     echo "❌ Docker Compose is not installed"
     exit 1
 fi
 
 COMPOSE_CMD="docker compose"
-if command -v docker-compose &>/dev/null; then
+if command -v docker-compose &> /dev/null; then
     COMPOSE_CMD="docker-compose"
 fi
 
-echo "📦 Building and starting Go backend + React frontend + PostgreSQL..."
+echo "📦 Building and starting services..."
 $COMPOSE_CMD -f docker-compose.dev.yml up -d --build
 
 echo "⏳ Waiting for services to become healthy..."
-sleep 10
+sleep 15
 
 echo "✅ Deployment complete!"
 echo ""
 echo "Services running:"
 echo "  • PostgreSQL:    localhost:5433"
-echo "  • Extrudex API (Go):   http://localhost:5080"
+echo "  • Extrudex API: http://localhost:5080"
-echo "  • Extrudex Web (React): http://localhost:5081"
+echo "  • Extrudex Web: http://localhost:5081"
-echo ""
-echo "Barcode scanner: HID keyboard input — focus any text field to start scanning."
-echo "Kiosk mode: Chromium auto-starts on boot via systemd (extrudex-kiosk.service)."
 echo ""
 echo "To view logs:"
 echo "  $COMPOSE_CMD -f docker-compose.dev.yml logs -f"
 echo ""
 echo "To stop:"
-echo "  $COMPOSE_CMD -f docker-compose.dev.yml down"
+echo "  $COMPOSE_CMD -f docker-compose.dev.yml down"

docker-compose.dev.yml

@@ -28,10 +28,13 @@ services:
     ports:
       - "5080:8080"
     environment:
-      - DATABASE_URL=postgres://extrudex:changeme@extrudex-db:5432/extrudex?sslmode=disable
+      - ASPNETCORE_ENVIRONMENT=Development
-      - PORT=8080
+      - ASPNETCORE_URLS=http://+:8080
-      - CORS_ORIGIN=*
+      - EXTRUDEX_DB_HOST=extrudex-db
-      - LOG_LEVEL=info
+      - EXTRUDEX_DB_PORT=5432
+      - EXTRUDEX_DB_NAME=extrudex
+      - EXTRUDEX_DB_USER=extrudex
+      - EXTRUDEX_DB_PASSWORD=changeme
     depends_on:
       extrudex-db:
         condition: service_healthy
@@ -41,7 +44,7 @@ services:
       interval: 30s
       timeout: 10s
       retries: 3
-      start_period: 15s
+      start_period: 40s
     networks:
       - extrudex-network
 

docs/CONTEXT.md

@@ -0,0 +1,214 @@
+# Extrudex — Project Context
+
+> **Last updated:** 2026-05-21
+> **Repo:** `CubeCraft-Creations/Extrudex` | **Host:** `code.cubecraftcreations.com`
+> **Local clone:** `/mnt/ai-storage/projects/Extrudex` | **Default branch:** `dev`
+> **Discord:** `DISCORD_DEV_EXTRUDEX_CHANNEL_ID`
+> **Linear Epic:** [CUB-110](https://linear.app/cubecraft-creations/issue/CUB-110)
+
+---
+
+## Overview
+
+Custom filament inventory and print tracking system for CubeCraft Creations. Tracks spool consumption, material costs, and per-print COGS across a fleet of 6 FDM printers (5 Bambu Lab + 1 Elegoo Centauri Carbon) + resin printers. Kiosk interface on Raspberry Pi 5 with USB barcode scanner.
+
+**Active refactor in progress:** .NET → Go + React (CUB-110 epic).
+
+## Tech Stack
+
+| Layer | Technology | Notes |
+|-------|-----------|-------|
+| Backend (legacy) | ASP.NET Core 9 + EF Core | Being replaced by Go |
+| Backend (new) | Go 1.24+ | Chi router, pgx (PostgreSQL), gorilla/websocket, paho.mqtt.golang |
+| Frontend (legacy) | Angular 17+ | Being replaced by React |
+| Frontend (new) | React 18 + TypeScript + Tailwind CSS | Vite |
+| Database | PostgreSQL 16+ | snake_case naming |
+| Real-time | SSE (Server-Sent Events) | Replaces SignalR |
+| Printer integrations | Moonraker REST + WebSocket, MQTT TLS | Elegoo/Klipper + Bambu Lab |
+| CI/CD | Gitea Actions | `.gitea/workflows/dev.yml` |
+| Deployment | Docker/Compose, Pi 5 kiosk | |
+
+## Key Design Decisions
+
+1. **Custom system over Spoolman** — Full control over data model and integrations
+2. **MaterialFinish required** on every spool; default is "Basic"
+3. **MaterialModifier is optional**
+4. **Grams derived from:** `mm_extruded × filament_cross_section_area × material_density`
+5. **Push over poll** — SSE + MQTT preferred; Moonraker polling is fallback
+6. **Snake_case** for all PostgreSQL identifiers
+
+## Project Structure
+
+```
+Extrudex/
+├── backend/                         # Original .NET backend (being replaced)
+│   ├── API/Controllers/             # Filaments, Spools, PrintJobs, Printers, Materials, QR, UsageLogs, Cost
+│   ├── API/DTOs/                    # DTOs per domain
+│   ├── API/Validators/              # FluentValidation rules
+│   ├── API/Hubs/                    # SignalR PrinterHub
+│   ├── API/Jobs/                    # Background sync jobs
+│   ├── Domain/Entities/             # EF Core entities (Printer, Spool, PrintJob, MaterialBase, etc.)
+│   ├── Domain/Enums/                # ConnectionType, DataSource, JobStatus, PrinterStatus, QrResourceType
+│   ├── Domain/Interfaces/           # Service interfaces
+│   ├── Infrastructure/Data/         # EF DbContext, Configurations, Migrations, SeedData
+│   ├── Infrastructure/Services/     # MoonrakerClient, CostPerPrint, UsageLog, FilamentUsage, QR
+│   └── Program.cs                  # ASP.NET entry point
+├── cmd/server/main.go              # Go entrypoint (new), worker discovery, graceful shutdown
+├── internal/                       # Go backend (new)
+│   ├── config/config.go            # Env vars
+│   ├── db/db.go                    # PostgreSQL connection pool (pgx)
+│   ├── models/models.go            # Go domain structs
+│   ├── router/router.go            # Chi HTTP routes
+│   ├── sse/broadcaster.go          # SSE broadcaster
+│   ├── sse/events.go               # SSE event types
+│   ├── sse/handler.go              # SSE HTTP handler
+│   ├── handlers/                   # API handlers (filament, health, material, print_job, printer, usage_log)
+│   ├── repositories/               # DB access layer
+│   └── services/                   # Business logic + validation
+├── migrations/                     # Go-migrate SQL migrations
+│   ├── 000001_initial_schema.up.sql
+│   ├── 000001_initial_schema.down.sql
+│   ├── 000002_seed_data.up.sql
+│   └── 000002_seed_data.down.sql
+├── frontend/                       # React frontend (new)
+│   ├── src/
+│   │   ├── App.tsx
+│   │   ├── main.tsx
+│   │   ├── components/             # ColorSwatch, LoadingSpinner, RecentPrints, SummaryCard
+│   │   ├── pages/
+│   │   │   ├── Dashboard.tsx       # Main dashboard with summary cards + recent prints
+│   │   │   └── InventoryPage.tsx   # Filament inventory list (table + filters)
+│   │   ├── services/
+│   │   │   ├── api.ts              # Axios client
+│   │   │   └── filamentService.ts
+│   │   ├── stores/                 # State stores (WIP)
+│   │   ├── types/
+│   │   │   ├── filament.ts
+│   │   │   └── index.ts
+│   │   └── hooks/
+│   ├── Dockerfile + nginx.conf
+│   └── vite.config.ts, tailwind.config.js
+├── design/                         # UX/design specs + mockup images
+│   ├── homepage-spec.md
+│   ├── 01-filament-inventory-list.md
+│   ├── 02-spool-detail-view.md
+│   ├── 03-smart-intake-workflow.md
+│   ├── smart-intake-identify-spec.md
+│   └── *.jpg / *.png               # Mockup images (kiosk + mobile)
+├── docker-compose.dev.yml
+└── deploy.sh
+```
+
+## Database Schema (PostgreSQL — .NET EF Core Migrations)
+
+Core entities managed by EF Core with full configurations:
+- **Printers** — id, name, type (BambuLab/Moonraker), connection_type, status, ip_address, mac_address, ams_count
+- **AmsUnit / AmsSlot** — Bambu Lab AMS tray tracking
+- **Spools** — filament inventory with material, color, weight, location, QR support
+- **MaterialBase / MaterialFinish / MaterialModifier** — material taxonomy
+- **PrintJobs** — job tracking with status, cost, filament consumption
+- **UsageLogs** — per-printer filament consumption records
+- **FilamentUsage** — aggregated per-spool consumption tracking
+- **FilamentUsageSyncJob** — background Moonraker polling
+- **MoonrakerPrinterSyncJob** — background printer status sync
+
+## API Endpoints (.NET)
+
+| Method | Endpoint | Description |
+|--------|----------|-------------|
+| GET | /api/filaments | List filaments (paginated, filterable) |
+| POST | /api/filaments | Create filament |
+| GET | /api/filaments/{id} | Get filament detail |
+| PUT | /api/filaments/{id} | Update filament |
+| DELETE | /api/filaments/{id} | Delete filament |
+| GET | /api/spools | List spools |
+| POST | /api/spools | Create spool |
+| GET | /api/spools/{id} | Get spool detail |
+| PUT | /api/spools/{id} | Update spool |
+| DELETE | /api/spools/{id} | Delete spool |
+| GET | /api/print-jobs | List print jobs |
+| POST | /api/print-jobs | Create print job |
+| GET | /api/print-jobs/{id} | Get print job detail |
+| GET | /api/printers | List printers |
+| POST | /api/printers | Register printer |
+| GET | /api/printers/{id} | Get printer detail |
+| GET | /api/printers/{id}/costs | Per-print cost summary |
+| GET | /api/printers/{id}/usage | Filament usage history |
+| GET | /api/materials/bases | List material bases |
+| POST | /api/materials/bases | Create material base |
+| GET | /api/materials/finishes | List material finishes |
+| POST | /api/materials/finishes | Create material finish |
+| GET | /api/materials/modifiers | List material modifiers |
+| POST | /api/materials/modifiers | Create modifier |
+| GET | /api/materials/lookups | Unified material lookup |
+| GET | /api/qr/resolve/{code} | QR code resolve |
+| GET | /api/usage-logs | List usage logs |
+| POST | /api/usage-logs | Create usage log |
+
+## CUB-110 Epic Progress (Go + React Rewrite)
+
+| Sub-task | Title | Status | Agent |
+|----------|-------|--------|-------|
+| CUB-111 | Design PostgreSQL schema | Done | Hex |
+| CUB-112 | Scaffold Go backend | Done | Dex |
+| CUB-113 | Core CRUD API endpoints | Done | Dex |
+| CUB-116 | Scaffold React frontend | In Review | Rex |
+| CUB-117 | Moonraker + MQTT integrations | In Progress | Dex |
+| CUB-118 | (deprecated → CUB-135 + CUB-136) | — | — |
+| CUB-130 | Add/Edit Filament form | In Review | Rex |
+| CUB-131 | Filament Detail page | In Review | Rex |
+| CUB-132 | Filament Inventory list | Done | Rex |
+| CUB-133 | Dashboard summary cards | In Review | Rex |
+| CUB-134 | Printers list page | Todo | Rex |
+| CUB-135 | Subscribe to SSE in React | In Review | Rex |
+| CUB-136 | Add SSE endpoint in Go | In Review | Dex |
+| CUB-128 | Settings page | Todo | — |
+| CUB-129 | Print Jobs list page | Todo | — |
+| CUB-114 | Pi 5 kiosk deployment | Todo | — |
+
+## Active Branches
+
+| Branch | Agent | Issue | Status |
+|--------|-------|-------|--------|
+| `agent/dex/CUB-117-moonraker-mqtt-go` | Dex | CUB-117 | Local commit ready |
+| `agent/dex/CUB-136-sse-endpoint` | Dex | CUB-136 | PR open |
+| `agent/rex/CUB-130-filament-form` | Rex | CUB-130 | PR open |
+| `agent/rex/CUB-131-filament-detail` | Rex | CUB-131 | PR open |
+| `agent/rex/CUB-133-dashboard-cards` | Rex | CUB-133 | PR open |
+| `agent/rex/CUB-135-sse-subscribe` | Rex | CUB-135 | PR open |
+
+## Known Limitations
+
+- Go rewrite is in progress — backend `internal/` is new Go code, but legacy .NET code still serves endpoints
+- Kiosk deployment not finalized (CUB-114)
+- Smart intake workflow is designed but not implemented
+- MQTT Bambu Lab integration is partially complete (CUB-117)
+
+## Default Agent Assignments
+
+| Area | Agent | Notes |
+|------|-------|-------|
+| Backend (Go API, Moonraker, MQTT) | Dex | gitea-dex MCP |
+| Database (PostgreSQL schema, migrations) | Hex | gitea-hex MCP |
+| Frontend (React, Tailwind) | Rex | gitea-rex MCP |
+| Design (wireframes, UX) | Sketch | |
+
+## Getting Started
+
+```bash
+cd /mnt/ai-storage/projects/Extrudex
+git checkout dev
+git pull origin dev
+
+# Legacy .NET backend
+cd backend && dotnet run
+
+# New Go backend
+go run cmd/server/main.go
+
+# React frontend
+cd frontend && npm install && npm run dev
+
+# Docker
+docker compose -f docker-compose.dev.yml up --build
+```

docs/PI-KIOSK-SETUP.md

@@ -1,168 +0,0 @@
-# Pi 5 Kiosk Setup — Extrudex (Go + React)
-
-## Prerequisites
-
-- Raspberry Pi 5 (4 GB or 8 GB)
-- MicroSD card (32 GB minimum, Class 10+)
-- HDMI touchscreen display
-- USB barcode scanner (HID keyboard mode)
-- Power supply (27W USB-C recommended)
-
-## One-Line Setup
-
-```bash
-# 1. Install Raspberry Pi OS (64-bit, Desktop)
-# 2. Enable SSH and VNC
-# 3. Run the automated bootstrap
-curl -sSL https://raw.githubusercontent.com/CubeCraft-Creations/Extrudex/dev/scripts/pi-bootstrap.sh | bash
-```
-
-Or follow the manual steps below.
-
-## Manual Setup
-
-### 1. Install Docker
-
-```bash
-curl -fsSL https://get.docker.com | sh
-sudo usermod -aG docker pi
-```
-
-Log out and back in for group changes to take effect.
-
-### 2. Clone and deploy
-
-```bash
-cd /home/pi
-git clone https://code.cubecraftcreations.com/CubeCraft-Creations/Extrudex.git
-cd Extrudex
-git checkout dev
-
-# Run the deploy script
-chmod +x deploy.sh
-./deploy.sh
-```
-
-### 3. Verify services
-
-```bash
-docker compose -f docker-compose.dev.yml ps
-# All three services should be "Up"
-```
-
-Check the health endpoint:
-```bash
-curl http://localhost:5080/health
-# Expected: {"status":"ok","db_connected":true,"timestamp":"..."}
-```
-
-### 4. Configure kiosk auto-start
-
-```bash
-# Enable the Docker stack service (starts on boot)
-sudo cp systemd/extrudex.service /etc/systemd/system/
-sudo systemctl daemon-reload
-sudo systemctl enable extrudex.service
-
-# Enable the kiosk service (starts Chromium after Docker stack)
-sudo cp systemd/extrudex-kiosk.service /etc/systemd/system/
-sudo systemctl daemon-reload
-sudo systemctl enable extrudex-kiosk.service
-```
-
-### 5. Configure display server
-
-For Pi 5, Raspberry Pi OS uses Wayland by default. If you encounter
-X11-specific issues, switch to X11 in raspi-config (Advanced Options →
-Resolution → X11).
-
-The kiosk service supports both Wayland and X11 display servers.
-
-### 6. Touchscreen calibration (if needed)
-
-```bash
-# Install calibration tools
-sudo apt install -y xinput-calibrator
-
-# Run calibration, note the device ID and parameters
-xinput_calibrator
-```
-
-Add the calibration to `~/.config/labwc/labwc.conf` or `/etc/X11/xorg.conf.d/`
-as appropriate for your display server.
-
-## USB Barcode Scanner
-
-The USB barcode scanner works as a HID keyboard device — it types scanned
-codes followed by an Enter keypress. No driver configuration is needed.
-
-On the React frontend, the search input auto-focuses on page load and
-will capture barcode input immediately. After a touch on another element,
-tap the search field again to re-focus.
-
-## Auto-Refresh on Wake
-
-The React app polls the SSE endpoint every 30 seconds for real-time
-updates. When the Pi wakes from sleep, the next poll will immediately
-sync the UI.
-
-The kiosk service has `Restart=always` and `RestartSec=10`, so Chromium
-will restart within 10 seconds of any crash or power cycle.
-
-## Touch Gestures
-
-Chromium is launched with `--touch-events=enabled` and `--enable-pinch`
-for native touch gesture support:
-- **Tap** — click/submit
-- **Two-finger scroll** — page scrolling
-- **Pinch** — zoom (disabled in kiosk mode by default; enable if needed)
-
-## Troubleshooting
-
-### Services not starting
-```bash
-sudo systemctl status extrudex
-sudo systemctl status extrudex-kiosk
-docker compose -f docker-compose.dev.yml logs
-```
-
-### Kiosk shows blank page
-- Ensure Docker stack is running: `docker compose ps`
-- Check nginx is serving the React build: `curl http://localhost:5081`
-- Check Chromium logs: `journalctl -u extrudex-kiosk -n 50`
-
-### Barcode not working
-- Verify scanner is in HID keyboard mode (most USB scanners default to this)
-- Open a text field and scan — you should see digits appear
-- Check with `dmesg | grep -i usb` for device enumeration
-
-### PostgreSQL connection refused
-```bash
-docker compose -f docker-compose.dev.yml restart extrudex-db
-# Wait 15 seconds, then check health
-curl http://localhost:5080/health
-```
-
-## Architecture
-
-```
-┌──────────────────────────────────────────────┐
-│  Pi 5 (Raspberry Pi OS 64-bit)               │
-│                                              │
-│  ┌─────────────┐  ┌──────────┐  ┌─────────┐ │
-│  │ Chromium    │  │  Nginx   │  │  Go     │ │
-│  │ Kiosk       │→│  (React) │→│  API    │ │
-│  │ :5081       │  │  :5080   │  │  :8080  │ │
-│  └─────────────┘  └──────────┘  └────┬────┘ │
-│                                       │      │
-│                              ┌────────▼────┐ │
-│                              │  PostgreSQL │ │
-│                              │  :5432      │ │
-│                              └─────────────┘ │
-│                                              │
-│  ┌──────────┐                                │
-│  │  USB     │                                │
-│  │ Scanner  │ → HID keyboard → Browser       │
-│  └──────────┘                                │
-└──────────────────────────────────────────────┘
-```

frontend/nginx.conf

@@ -10,7 +10,7 @@ server {
     }
 
     location /api/ {
-        proxy_pass http://extrudex-api:8080/api/;
+        proxy_pass http://backend:8080/api/;
         proxy_http_version 1.1;
         proxy_set_header Upgrade $http_upgrade;
         proxy_set_header Connection 'upgrade';

frontend/package-lock.json

@@ -25,9 +25,11 @@
         "eslint": "^9.15.0",
         "eslint-plugin-react-hooks": "^5.0.0",
         "eslint-plugin-react-refresh": "^0.4.14",
+        "globals": "^17.6.0",
         "postcss": "^8.4.49",
         "tailwindcss": "^4.0.0",
         "typescript": "~5.6.0",
+        "typescript-eslint": "^8.60.0",
         "vite": "^6.0.0"
       }
     },
@@ -822,6 +824,18 @@
         "url": "https://opencollective.com/eslint"
       }
     },
+    "node_modules/@eslint/eslintrc/node_modules/globals": {
+      "version": "14.0.0",
+      "resolved": "https://registry.npmjs.org/globals/-/globals-14.0.0.tgz",
+      "integrity": "sha512-oahGvuMGQlPw/ivIYBjVSrWAfWLBeku5tpPE2fOPLi+WHffIWbuh2tCjhyQhTBPMf5E9jDEH4FOmTYgYwbKwtQ==",
+      "dev": true,
+      "engines": {
+        "node": ">=18"
+      },
+      "funding": {
+        "url": "https://github.com/sponsors/sindresorhus"
+      }
+    },
     "node_modules/@eslint/js": {
       "version": "9.39.4",
       "resolved": "https://registry.npmjs.org/@eslint/js/-/js-9.39.4.tgz",
@@ -1658,6 +1672,285 @@
         "@types/react": "^19.2.0"
       }
     },
+    "node_modules/@typescript-eslint/eslint-plugin": {
+      "version": "8.60.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/eslint-plugin/-/eslint-plugin-8.60.0.tgz",
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+      "dev": true,
+      "dependencies": {
+        "@eslint-community/regexpp": "^4.12.2",
+        "@typescript-eslint/scope-manager": "8.60.0",
+        "@typescript-eslint/type-utils": "8.60.0",
+        "@typescript-eslint/utils": "8.60.0",
+        "@typescript-eslint/visitor-keys": "8.60.0",
+        "ignore": "^7.0.5",
+        "natural-compare": "^1.4.0",
+        "ts-api-utils": "^2.5.0"
+      },
+      "engines": {
+        "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
+      },
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+      },
+      "peerDependencies": {
+        "@typescript-eslint/parser": "^8.60.0",
+        "eslint": "^8.57.0 || ^9.0.0 || ^10.0.0",
+        "typescript": ">=4.8.4 <6.1.0"
+      }
+    },
+    "node_modules/@typescript-eslint/eslint-plugin/node_modules/ignore": {
+      "version": "7.0.5",
+      "resolved": "https://registry.npmjs.org/ignore/-/ignore-7.0.5.tgz",
+      "integrity": "sha512-Hs59xBNfUIunMFgWAbGX5cq6893IbWg4KnrjbYwX3tx0ztorVgTDA6B2sxf8ejHJ4wz8BqGUMYlnzNBer5NvGg==",
+      "dev": true,
+      "engines": {
+        "node": ">= 4"
+      }
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+      "dev": true,
+      "dependencies": {
+        "@typescript-eslint/scope-manager": "8.60.0",
+        "@typescript-eslint/types": "8.60.0",
+        "@typescript-eslint/typescript-estree": "8.60.0",
+        "@typescript-eslint/visitor-keys": "8.60.0",
+        "debug": "^4.4.3"
+      },
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+      }
+    },
+    "node_modules/@typescript-eslint/visitor-keys/node_modules/eslint-visitor-keys": {
+      "version": "5.0.1",
+      "resolved": "https://registry.npmjs.org/eslint-visitor-keys/-/eslint-visitor-keys-5.0.1.tgz",
+      "integrity": "sha512-tD40eHxA35h0PEIZNeIjkHoDR4YjjJp34biM0mDvplBe//mB+IHCqHDGV7pxF+7MklTvighcCPPZC7ynWyjdTA==",
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+      },
+      "funding": {
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+      }
+    },
     "node_modules/@vitejs/plugin-react": {
       "version": "4.7.0",
       "resolved": "https://registry.npmjs.org/@vitejs/plugin-react/-/plugin-react-4.7.0.tgz",
@@ -2528,9 +2821,9 @@
       }
     },
     "node_modules/globals": {
-      "version": "14.0.0",
+      "version": "17.6.0",
-      "resolved": "https://registry.npmjs.org/globals/-/globals-14.0.0.tgz",
+      "resolved": "https://registry.npmjs.org/globals/-/globals-17.6.0.tgz",
-      "integrity": "sha512-oahGvuMGQlPw/ivIYBjVSrWAfWLBeku5tpPE2fOPLi+WHffIWbuh2tCjhyQhTBPMf5E9jDEH4FOmTYgYwbKwtQ==",
+      "integrity": "sha512-sepffkT8stwnIYbsMBpoCHJuJM5l98FUF2AnE07hfvE0m/qp3R586hw4jF4uadbhvg1ooIdzuu7CsfD2jzCaNA==",
       "dev": true,
       "engines": {
         "node": ">=18"
@@ -3504,6 +3797,18 @@
         "url": "https://github.com/sponsors/SuperchupuDev"
       }
     },
+    "node_modules/ts-api-utils": {
+      "version": "2.5.0",
+      "resolved": "https://registry.npmjs.org/ts-api-utils/-/ts-api-utils-2.5.0.tgz",
+      "integrity": "sha512-OJ/ibxhPlqrMM0UiNHJ/0CKQkoKF243/AEmplt3qpRgkW8VG7IfOS41h7V8TjITqdByHzrjcS/2si+y4lIh8NA==",
+      "dev": true,
+      "engines": {
+        "node": ">=18.12"
+      },
+      "peerDependencies": {
+        "typescript": ">=4.8.4"
+      }
+    },
     "node_modules/type-check": {
       "version": "0.4.0",
       "resolved": "https://registry.npmjs.org/type-check/-/type-check-0.4.0.tgz",
@@ -3529,6 +3834,29 @@
         "node": ">=14.17"
       }
     },
+    "node_modules/typescript-eslint": {
+      "version": "8.60.0",
+      "resolved": "https://registry.npmjs.org/typescript-eslint/-/typescript-eslint-8.60.0.tgz",
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+        "@typescript-eslint/eslint-plugin": "8.60.0",
+        "@typescript-eslint/parser": "8.60.0",
+        "@typescript-eslint/typescript-estree": "8.60.0",
+        "@typescript-eslint/utils": "8.60.0"
+      },
+      "engines": {
+        "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
+      },
+      "funding": {
+        "type": "opencollective",
+        "url": "https://opencollective.com/typescript-eslint"
+      },
+      "peerDependencies": {
+        "eslint": "^8.57.0 || ^9.0.0 || ^10.0.0",
+        "typescript": ">=4.8.4 <6.1.0"
+      }
+    },
     "node_modules/update-browserslist-db": {
       "version": "1.2.3",
       "resolved": "https://registry.npmjs.org/update-browserslist-db/-/update-browserslist-db-1.2.3.tgz",

frontend/package.json

@@ -27,9 +27,11 @@
     "eslint": "^9.15.0",
     "eslint-plugin-react-hooks": "^5.0.0",
     "eslint-plugin-react-refresh": "^0.4.14",
+    "globals": "^17.6.0",
     "postcss": "^8.4.49",
     "tailwindcss": "^4.0.0",
     "typescript": "~5.6.0",
+    "typescript-eslint": "^8.60.0",
     "vite": "^6.0.0"
   }
 }

frontend/src/App.tsx

@@ -2,25 +2,35 @@ import { QueryClient, QueryClientProvider } from '@tanstack/react-query'
 import { BrowserRouter, Routes, Route } from 'react-router-dom'
 import Dashboard from './pages/Dashboard'
 import InventoryPage from './pages/InventoryPage'
+import ToastContainer from './components/ToastContainer'
+import { useSSE } from './hooks/useSSE'
 
 const queryClient = new QueryClient()
 
+function SSEProvider({ children }: { children: React.ReactNode }) {
+  useSSE()
+  return <>{children}</>
+}
+
 export default function App() {
   return (
     <QueryClientProvider client={queryClient}>
       <BrowserRouter>
-        <div className="min-h-screen bg-slate-900 text-slate-50">
+        <SSEProvider>
-          <header className="bg-slate-800 border-b border-slate-700 px-4 py-3 flex items-center gap-3 sticky top-0 z-20">
+          <div className="min-h-screen bg-slate-900 text-slate-50">
-            <div className="w-8 h-8 rounded bg-emerald-500 flex items-center justify-center text-slate-900 font-bold text-lg">E</div>
+            <header className="bg-slate-800 border-b border-slate-700 px-4 py-3 flex items-center gap-3 sticky top-0 z-20">
-            <h1 className="text-lg font-semibold">Extrudex</h1>
+              <div className="w-8 h-8 rounded bg-emerald-500 flex items-center justify-center text-slate-900 font-bold text-lg">E</div>
-          </header>
+              <h1 className="text-lg font-semibold">Extrudex</h1>
-          <main className="p-4">
+            </header>
-            <Routes>
+            <main className="p-4">
-              <Route path="/" element={<Dashboard />} />
+              <Routes>
-              <Route path="/inventory" element={<InventoryPage />} />
+                <Route path="/" element={<Dashboard />} />
-            </Routes>
+                <Route path="/inventory" element={<InventoryPage />} />
-          </main>
+              </Routes>
-        </div>
+            </main>
+          </div>
+          <ToastContainer />
+        </SSEProvider>
       </BrowserRouter>
     </QueryClientProvider>
   )

frontend/src/components/PrinterStatusBadge.tsx

@@ -0,0 +1,17 @@
+import { Printer } from 'lucide-react'
+
+const STYLES = {
+  online: 'bg-emerald-600 text-white',
+  offline: 'bg-slate-600 text-slate-200',
+  printing: 'bg-blue-600 text-white animate-pulse',
+}
+
+export default function PrinterStatusBadge({ status, name }: { status: string; name?: string }) {
+  const style = STYLES[status as keyof typeof STYLES] ?? STYLES.offline
+  return (
+    <span className={`inline-flex items-center gap-1.5 rounded-full px-2.5 py-1 text-xs font-medium ${style}`}>
+      <Printer size={12} />
+      {name ? `${name} · ${status}` : status}
+    </span>
+  )
+}

frontend/src/components/ToastContainer.tsx

@@ -0,0 +1,70 @@
+import { useEffect, useState, useCallback } from 'react'
+import { X, CheckCircle, AlertTriangle, Info } from 'lucide-react'
+import { addToastListener, type ToastMessage } from '../hooks/useSSE'
+
+const ICONS = {
+  info: Info,
+  success: CheckCircle,
+  warning: AlertTriangle,
+}
+
+const STYLES = {
+  info: 'border-blue-600 bg-blue-900/40 text-blue-100',
+  success: 'border-emerald-600 bg-emerald-900/40 text-emerald-100',
+  warning: 'border-amber-600 bg-amber-900/40 text-amber-100',
+}
+
+export default function ToastContainer() {
+  const [toasts, setToasts] = useState<ToastMessage[]>([])
+
+  const remove = useCallback((id: string) => {
+    setToasts(prev => prev.filter(t => t.id !== id))
+  }, [])
+
+  useEffect(() => {
+    return addToastListener((toast) => {
+      setToasts(prev => {
+        // Prevent duplicate identical toasts within 3 seconds
+        const now = Date.now()
+        const recent = prev.filter(
+          t => t.title === toast.title && now - parseInt(t.id.split('-').pop() || '0', 10) < 3000
+        )
+        if (recent.length > 0) return prev
+        return [...prev.slice(-4), toast]
+      })
+      // Auto-dismiss after 5 seconds
+      setTimeout(() => remove(toast.id), 5000)
+    })
+  }, [remove])
+
+  return (
+    <div className="fixed bottom-4 right-4 z-50 flex flex-col gap-2 max-w-sm w-full pointer-events-none">
+      {toasts.map((toast) => {
+        const Icon = ICONS[toast.type]
+        return (
+          <div
+            key={toast.id}
+            className={`pointer-events-auto rounded-lg border px-4 py-3 shadow-lg backdrop-blur-sm transition-all ${STYLES[toast.type]}`}
+          >
+            <div className="flex items-start gap-3">
+              <Icon size={18} className="mt-0.5 shrink-0" />
+              <div className="flex-1 min-w-0">
+                <p className="text-sm font-semibold leading-snug">{toast.title}</p>
+                {toast.body && (
+                  <p className="text-xs opacity-80 mt-0.5">{toast.body}</p>
+                )}
+              </div>
+              <button
+                onClick={() => remove(toast.id)}
+                className="shrink-0 -mr-1 -mt-1 p-1 rounded hover:bg-white/10 text-current opacity-70 hover:opacity-100 transition-opacity"
+                aria-label="Dismiss"
+              >
+                <X size={14} />
+              </button>
+            </div>
+          </div>
+        )
+      })}
+    </div>
+  )
+}

frontend/src/hooks/useSSE.ts

@@ -0,0 +1,193 @@
+import { useEffect, useRef, useCallback } from 'react'
+import { useQueryClient } from '@tanstack/react-query'
+
+export type SSEEventType =
+  | 'printer.status'
+  | 'job.started'
+  | 'job.completed'
+  | 'filament.low'
+
+export interface SSEEvent {
+  type: SSEEventType
+  payload: unknown
+  timestamp: string
+}
+
+export interface ToastMessage {
+  id: string
+  type: 'info' | 'success' | 'warning'
+  title: string
+  body?: string
+}
+
+let toastListeners: Array<(toast: ToastMessage) => void> = []
+
+export function addToastListener(cb: (toast: ToastMessage) => void) {
+  toastListeners.push(cb)
+  return () => {
+    toastListeners = toastListeners.filter(l => l !== cb)
+  }
+}
+
+function emitToast(toast: ToastMessage) {
+  toastListeners.forEach(cb => cb(toast))
+}
+
+const RECONNECT_BASE_MS = 1000
+const RECONNECT_MAX_MS = 30000
+
+export function useSSE(enabled = true) {
+  const queryClient = useQueryClient()
+  const esRef = useRef<EventSource | null>(null)
+  const reconnectTimerRef = useRef<ReturnType<typeof setTimeout> | null>(null)
+  const attemptRef = useRef(0)
+
+  const connect = useCallback(() => {
+    if (!enabled) return
+    if (esRef.current) {
+      esRef.current.close()
+    }
+
+    const es = new EventSource('/api/events')
+    esRef.current = es
+
+    es.onopen = () => {
+      attemptRef.current = 0
+    }
+
+    es.addEventListener('printer.status', (e) => {
+      try {
+        const data = JSON.parse(e.data) as SSEEvent
+        const payload = data.payload as {
+          printer_id: number
+          printer_name: string
+          status: string
+        }
+        // Update printer list cache if it exists
+        queryClient.setQueryData(['printers'], (old: unknown) => {
+          if (!Array.isArray(old)) return old
+          return old.map((p: Record<string, unknown>) =>
+            p.id === payload.printer_id
+              ? { ...p, status: payload.status, name: payload.printer_name }
+              : p
+          )
+        })
+      } catch {
+        // ignore malformed event
+      }
+    })
+
+    es.addEventListener('job.started', (e) => {
+      try {
+        const data = JSON.parse(e.data) as SSEEvent
+        const payload = data.payload as {
+          job_id: number
+          job_name: string
+          printer_id: number
+          spool_id?: number
+        }
+        emitToast({
+          id: `job-started-${payload.job_id}-${Date.now()}`,
+          type: 'info',
+          title: `Job started: ${payload.job_name}`,
+          body: `Printer #${payload.printer_id}`,
+        })
+        // Invalidate print jobs list
+        queryClient.invalidateQueries({ queryKey: ['print-jobs'] })
+      } catch {
+        // ignore malformed event
+      }
+    })
+
+    es.addEventListener('job.completed', (e) => {
+      try {
+        const data = JSON.parse(e.data) as SSEEvent
+        const payload = data.payload as {
+          job_id: number
+          job_name: string
+          printer_id: number
+          duration_seconds?: number
+          total_grams_used?: number
+          total_cost_usd?: number
+        }
+        const parts: string[] = []
+        if (payload.duration_seconds != null) {
+          const mins = Math.round(payload.duration_seconds / 60)
+          parts.push(`${mins} min`)
+        }
+        if (payload.total_grams_used != null) {
+          parts.push(`${payload.total_grams_used.toFixed(1)} g used`)
+        }
+        emitToast({
+          id: `job-completed-${payload.job_id}-${Date.now()}`,
+          type: 'success',
+          title: `Job completed: ${payload.job_name}`,
+          body: parts.join(' · ') || `Printer #${payload.printer_id}`,
+        })
+        queryClient.invalidateQueries({ queryKey: ['print-jobs'] })
+        queryClient.invalidateQueries({ queryKey: ['filaments'] })
+      } catch {
+        // ignore malformed event
+      }
+    })
+
+    es.addEventListener('filament.low', (e) => {
+      try {
+        const data = JSON.parse(e.data) as SSEEvent
+        const payload = data.payload as {
+          spool_id: number
+          spool_name: string
+          remaining_grams: number
+          threshold_grams: number
+        }
+        emitToast({
+          id: `filament-low-${payload.spool_id}-${Date.now()}`,
+          type: 'warning',
+          title: `Low filament: ${payload.spool_name}`,
+          body: `${payload.remaining_grams} g remaining (threshold ${payload.threshold_grams} g)`,
+        })
+        // Update filament inventory cache in place for instant UI feedback
+        queryClient.setQueryData(['filaments'], (old: unknown) => {
+          if (!old || typeof old !== 'object') return old
+          const o = old as { data?: Array<Record<string, unknown>>; total?: number }
+          if (!Array.isArray(o.data)) return old
+          return {
+            ...o,
+            data: o.data.map((f) =>
+              (f.id as number) === payload.spool_id
+                ? { ...f, remaining_grams: payload.remaining_grams }
+                : f
+            ),
+          }
+        })
+      } catch {
+        // ignore malformed event
+      }
+    })
+
+    es.onerror = () => {
+      es.close()
+      // Exponential backoff with jitter
+      const base = Math.min(RECONNECT_MAX_MS, RECONNECT_BASE_MS * 2 ** attemptRef.current)
+      const jitter = Math.random() * 1000
+      const delay = base + jitter
+      attemptRef.current += 1
+      reconnectTimerRef.current = setTimeout(() => {
+        connect()
+      }, delay)
+    }
+  }, [enabled, queryClient])
+
+  useEffect(() => {
+    connect()
+    return () => {
+      if (reconnectTimerRef.current) {
+        clearTimeout(reconnectTimerRef.current)
+      }
+      if (esRef.current) {
+        esRef.current.close()
+        esRef.current = null
+      }
+    }
+  }, [connect])
+}

frontend/src/pages/InventoryPage.tsx

@@ -35,7 +35,7 @@ export default function InventoryPage() {
     queryFn: () => fetchFilaments(filter),
   })
 
-  const filaments = data?.data ?? []
+  const filaments = useMemo(() => data?.data ?? [], [data?.data])
   const total = data?.total ?? 0
   const totalPages = Math.max(1, Math.ceil(total / PAGE_SIZE))
 

systemd/extrudex-kiosk.service

@@ -1,36 +0,0 @@
-[Unit]
-Description=Extrudex Kiosk (Chromium, Go + React frontend)
-After=network-online.target extrudex.service
-Requires=extrudex.service
-
-[Service]
-Type=simple
-User=pi
-Group=pi
-Environment=DISPLAY=:0
-Environment=XAUTHORITY=/home/pi/.Xauthority
-WorkingDirectory=/home/pi
-
-ExecStart=/usr/bin/chromium-browser \
-    --no-first-run \
-    --no-default-browser-check \
-    --autoplay-policy=no-user-gesture-required \
-    --disable-infobars \
-    --disable-window-activation \
-    --disable-full-screen-modal \
-    --kiosk http://localhost:5081 \
-    --disable-features=TranslateUI \
-    --touch-events=enabled \
-    --enable-pinch
-
-ExecReload=/bin/kill -HUP $MAINPID
-
-Restart=always
-RestartSec=10
-
-# Touchscreen / kiosk
-Environment=QT_QPA_PLATFORM=wayland
-Environment=QT_WAYLAND_SHELL_INTEGRATION=wayland
-
-[Install]
-WantedBy=multi-user.target

systemd/extrudex-kiosk@.service

@@ -1,12 +0,0 @@
-[Unit]
-Description=Extrudex Kiosk Session (user-level, seat %i)
-After=graphical-session.target
-
-[Service]
-Type=simple
-Environment=DISPLAY=:0
-ExecStart=/bin/true
-Restart=on-failure
-
-[Install]
-WantedBy=graphical-session.target

systemd/extrudex.service

@@ -1,16 +0,0 @@
-[Unit]
-Description=Extrudex Docker Compose Stack (Go + React)
-After=network-online.target docker.service
-Requires=docker.service
-
-[Service]
-Type=oneshot
-RemainAfterExit=yes
-WorkingDirectory=/home/pi/extrudex
-ExecStart=/usr/bin/docker compose -f docker-compose.dev.yml up -d
-ExecStop=/usr/bin/docker compose -f docker-compose.dev.yml down
-TimeoutStartSec=120
-TimeoutStopSec=120
-
-[Install]
-WantedBy=multi-user.target