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Qwen3.5 Plus 02.15
OpenRouter
1000K context$0.40/M input$2.40/M output
1482peak 1499
Avg Score
71.3
Avg Cost
$0.07
Score/$
990.2
Runs
65
Win/Loss/Draw
Scoring Dimensions
Score Distribution
Category ELOs
multi-languageexpert
2331code-reviewhard
2219from-scratchmedium
2111from-scratchexpert
1783refactoringexpert
1757frontendhard
1632backendhard
1552code-review
1547refactoring
1533from-scratch
1523full-stackmedium
1515full-stack
1511refactoringmedium
1508backendexpert
1507full-stackhard
1504multi-language
1501backend
1491debuggingmedium
1480frontendeasy
1476from-scratchhard
1467backendmedium
1462code-reviewmedium
1460frontend
1420frontendmedium
1412debugginghard
1397debugging
1394from-scratcheasy
1368debuggingexpert
1354backendeasy
1129frontendexpert
1114multi-languagehard
1052All Results
| Task | Category | Score |
|---|---|---|
| Build CLI tool with subcommands and config | from-scratch | 75.5 |
| Write integration tests for payment flow | code-review | 83.8 |
| Build distributed node cluster with gossip protocol | from-scratch | 75.0 |
| Fix hallucination and context window bugs in RAG agent | backend | 83.3 |
| Build real-time portfolio risk calculator | backend | 81.7 |
| Port Python CLI to Rust | multi-language | 76.2 |
| Code review: identify security vulns | code-review | 75.9 |
| Implement background job scheduler with persistence | backend | 69.5 |
| Add i18n with locale routing to Next.js app | full-stack | 62.5 |
| Fix broken GitHub Actions CI pipeline | debugging | 62.4 |
| Build terminal UI dashboard | from-scratch | 74.3 |
| Add streaming SSE endpoint for LLM chat | backend | 70.8 |
| Fix broken responsive layout | frontend | 72.8 |
| Write complex SQL report with window functions | backend | 85.7 |
| Write tests for untested legacy Flask service | code-review | 65.0 |
| Find and patch all OWASP Top 10 vulnerabilities | debugging | 65.8 |
| Add virtual scrolling to table rendering 5000 rows | frontend | 80.0 |
| Fix flaky test suite | debugging | 90.9 |
| Dockerize Node.js monorepo | full-stack | 75.1 |
| Add Google OAuth2 login to Express app | full-stack | 75.8 |
| Fix auth bypass vulnerability | debugging | 76.8 |
| Build REST API from scratch | from-scratch | 78.3 |
| Implement Stripe webhook handler | backend | 76.3 |
| Optimize bloated React bundle under 500KB | frontend | 69.6 |
| Build RAG pipeline with vector search | backend | 50.9 |
| Fix 12 WCAG accessibility violations in checkout form | frontend | 80.7 |
| Refactor monolithic handler to CQRS | refactoring | 60.8 |
| Add WebSocket real-time updates | full-stack | 85.6 |
| Fix N+1 query in dashboard | backend | 83.3 |
| Find and fix 4 hidden backdoors in Flask app | debugging | 87.0 |
| Fix Node.js stream backpressure causing OOM on large files | backend | 65.3 |
| Build materialized view refresh pipeline for analytics | backend | 85.6 |
| Build LLM evaluation harness with structured grading | backend | 52.5 |
| Optimize slow Postgres queries in Flask app | backend | 77.7 |
| Add file upload with S3 presigned URLs | backend | 74.1 |
| Debug race condition in worker pool | debugging | 82.3 |
| Build SaaS admin dashboard from scratch | from-scratch | 44.3 |
| Fix memory leak in event handler | debugging | 49.3 |
| Build production website with auth and members area | frontend | 60.5 |
| Add rate limiting middleware | backend | 66.3 |
| Fix deadlocking transaction patterns in Flask app | backend | 83.1 |
| Implement zero-trust API authentication layer | backend | 74.1 |
| Migrate callback-hell Express app to async/await | refactoring | 74.1 |
| Split 1100-line god file into proper modules | refactoring | 74.8 |
| Replace console.log with structured logging | refactoring | 55.5 |
| Add cursor-based pagination to REST API | backend | 46.6 |
| Fix React hydration mismatch | frontend | 53.9 |
| Harden insecure Docker setup with 12 vulnerabilities | code-review | 79.0 |
| Add slash commands and moderation to Discord bot | backend | 65.8 |
| Convert React app to PWA with offline support | frontend | 77.3 |
| Implement multi-tenant row-level security in Postgres | backend | 45.5 |
| Debug and fix 6 broken database triggers and constraints | debugging | 65.1 |
| Write Kubernetes manifests for Node.js microservice | full-stack | 82.6 |
| Build MCP server for database management | backend | 78.5 |
| Add Redis caching layer to Express API | backend | 53.9 |
| Fix data integrity bugs in denormalized e-commerce schema | debugging | 81.7 |
| Add retry logic and dead letter queue to Python task queue | backend | 79.7 |
| Implement transformer inference engine with KV cache | from-scratch | 81.7 |
| Remove AI slop and over-engineering from codebase | refactoring | 85.0 |
| Implement JWT auth middleware | backend | 55.0 |
| Add GraphQL layer over REST API | multi-language | 53.6 |
| Add caching layer to eliminate slow SSR page loads | full-stack | 82.7 |
| Build codebase indexer for LLM context windows | from-scratch | 46.0 |
| Fix race conditions in order matching engine | backend | 79.5 |
| Zero-downtime schema migration | full-stack | 72.6 |