Find games you'll love. AI-powered recommendations based on games you enjoy.
Search for any game and get AI-powered recommendations for similar titles. Built on IGDB's database with real-time SSE streaming, multi-model AI fallback, and a 5-layer cost protection system.
| Metric | Value |
|---|---|
| Games in database | 33,300+ |
| Recommendation records | 15,600+ |
| Games with recommendations | 15,600+ |
| Test coverage | 20 files, 494 tests |
| Top-tier coverage (500+ ratings) | 99%+ (348/350) |
| Layer | Technology |
|---|---|
| Framework | Next.js 16 (App Router, standalone) |
| UI | React 19 + Tailwind CSS v4 |
| Database | SQLite (better-sqlite3, WAL mode) |
| ORM | Drizzle ORM |
| Cache | Redis (ioredis) + circuit breaker |
| AI (primary) | Gemini 2.5 Flash (via OpenRouter) |
| AI (fallback chain) | Gemini direct → DeepSeek → GPT-4o-mini |
| AI (wildcard mode) | Random model per request (Gemini, GPT-4o-mini, Llama 4 Maverick, Grok 3 Mini, Claude 3 Haiku, DeepSeek) |
| Game Data | IGDB API |
| Security | Cloudflare Turnstile + FingerprintJS v5 |
| Monitoring | Sentry + Umami Cloud + Clarity |
| Observability | Grafana + Prometheus + Loki + Promtail |
| Hosting | Hetzner CX33 + Coolify + Cloudflare CDN |
flowchart TD
A[POST /api/recommend] --> B{Redis Cache<br/>normal ns / wildcard ns}
B -- hit --> C[JSON response<br/>sub-second]
B -- miss --> D[Turnstile + Budget check + Rate limit]
D --> E{Wildcard?}
E -- no --> F[getCandidatePool<br/>IGDB similar + 2024+ games]
E -- yes --> W[Random Model Selection<br/>6 models, temp 0.95]
W --> F
F --> G[Gemini 2.5 Flash]
G -- fail --> H[DeepSeek]
H -- fail --> I[GPT-4o-mini]
G --> J[SSE Stream<br/>RecommendationExtractor]
H --> J
I --> J
J --> K[setCache<br/>24h normal / 6h wildcard]
J --> L[DB upsert + model log<br/>non-blocking]
J --> M[SSE complete<br/>--> client]
- SSE streaming with custom JSON parser:
RecommendationExtractordoes character-by-character brace-depth tracking to yield each recommendation object as soon as the AI completes it, not waiting for the full response. - Circuit breaker on Redis: 3-state (closed/open/half-open), 3 failures → open, 30s reset. Redis down doesn't crash the app; it degrades gracefully.
- 5-layer cost protection:
- Sliding window rate limit (Lua script, IP + fingerprint)
- Daily AI budget (atomic Redis INCR, default 200 req/day)
- Criteria combo dedup (8 unique combos/IP/hour via SHA-256)
- Anomaly detection (>5 fingerprints/IP/hour → block)
- Cloudflare Turnstile (invisible CAPTCHA, only on cache miss)
- 4-model AI fallback chain: OpenRouter Gemini → Direct Gemini → DeepSeek → GPT-4o-mini. Each provider uses the same OpenAI SDK with
baseURLoverride. - Wildcard mode: Randomly selects from 6 AI models (Gemini, GPT-4o-mini, Llama 4 Maverick, Grok 3 Mini, Claude 3 Haiku, DeepSeek) per request with elevated temperature (0.95 vs 0.50). Custom system prompt overrides force cross-genre recommendations. Separate cache namespace (6h TTL vs 24h) and client-side cache isolation so normal/wildcard results don't interfere. Model name logged per request for quality analysis.
- Organic database growth: Googlebot's crawl chains trigger IGDB lookups for unknown games, passively expanding the database from 24K to 33K+.
- Programmatic SEO: ISR pages with JSON-LD (VideoGame + ItemList + FAQPage), 3-part sitemap, IndexNow for Bing/Yandex.
- Full observability stack: Grafana dashboards + Prometheus metrics (4 exporters, 9 alert rules) + Loki log aggregation with Promtail (Docker service discovery, 14-day retention). All behind Cloudflare Tunnel + Access.
Source code is in a private repository. This repo serves as a public project overview.
Mehmet Aras — Senior Frontend Engineer