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Qwen3.5 Plus 02.15
OpenRouter
1000K context$0.40/M input$2.40/M output
1511peak 1534
Avg Score
58.1
Avg Cost
$0.10
Score/$
568.2
Runs
122
Win/Loss/Draw
Scoring Dimensions
Score Distribution
Category ELOs
refactoringexpert
2010from-scratchexpert
1809full-stackmedium
1756from-scratcheasy
1671refactoring
1666frontendeasy
1643frontendexpert
1641code-reviewmedium
1619refactoringmedium
1608backendexpert
1605frontendhard
1590from-scratchhard
1565debuggingexpert
1553backendmedium
1550backend
1529full-stack
1528from-scratch
1521code-review
1517frontend
1505backendhard
1501debugginghard
1455frontendmedium
1453debugging
1447full-stackhard
1302backendeasy
1268multi-languagehard
1268debuggingmedium
1110multi-language
1070from-scratchmedium
961code-reviewhard
307multi-languageexpert
0All Results
| Task | Category | Score |
|---|---|---|
| Fix hallucination and context window bugs in RAG agent | backend | 0.0 |
| Implement background job scheduler with persistence | backend | 0.0 |
| Add i18n with locale routing to Next.js app | full-stack | 28.0 |
| Fix broken GitHub Actions CI pipeline | debugging | — |
| Build terminal UI dashboard | from-scratch | 0.0 |
| Add streaming SSE endpoint for LLM chat | backend | — |
| Fix broken responsive layout | frontend | 22.0 |
| Write complex SQL report with window functions | backend | 0.0 |
| Write tests for untested legacy Flask service | code-review | 0.0 |
| Find and patch all OWASP Top 10 vulnerabilities | debugging | 28.0 |
| Add virtual scrolling to table rendering 5000 rows | frontend | — |
| Fix flaky test suite | debugging | 28.0 |
| Build CLI tool with subcommands and config | from-scratch | 0.0 |
| Dockerize Node.js monorepo | full-stack | 28.0 |
| Add Google OAuth2 login to Express app | full-stack | — |
| Fix auth bypass vulnerability | debugging | — |
| Build REST API from scratch | from-scratch | 22.0 |
| Implement Stripe webhook handler | backend | — |
| Optimize bloated React bundle under 500KB | frontend | 28.0 |
| Port Python CLI to Rust | multi-language | 0.0 |
| Build RAG pipeline with vector search | backend | 0.0 |
| Fix 12 WCAG accessibility violations in checkout form | frontend | 0.0 |
| Refactor monolithic handler to CQRS | refactoring | — |
| Add WebSocket real-time updates | full-stack | 28.0 |
| Build distributed node cluster with gossip protocol | from-scratch | 0.0 |
| Fix N+1 query in dashboard | backend | 0.0 |
| Find and fix 4 hidden backdoors in Flask app | debugging | 28.0 |
| Code review: identify security vulns | code-review | 0.0 |
| 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 | 53.3 |
| 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 |
| Write integration tests for payment flow | code-review | 45.8 |
| Add slash commands and moderation to Discord bot | backend | 65.8 |
| Build real-time portfolio risk calculator | backend | 44.0 |
| 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 |
| Split 1100-line god file into proper modules | refactoring | 67.9 |
| Remove AI slop and over-engineering from codebase | refactoring | 84.6 |
| Fix broken responsive layout | frontend | 78.0 |
| Implement JWT auth middleware | backend | 87.9 |
| Convert React app to PWA with offline support | frontend | 67.5 |
| Implement multi-tenant row-level security in Postgres | backend | 82.3 |
| Harden insecure Docker setup with 12 vulnerabilities | code-review | 85.4 |
| Add caching layer to eliminate slow SSR page loads | full-stack | 83.2 |
| Optimize bloated React bundle under 500KB | frontend | 67.1 |
| Implement zero-trust API authentication layer | backend | 71.1 |
| Dockerize Node.js monorepo | full-stack | 81.6 |
| Find and patch all OWASP Top 10 vulnerabilities | debugging | 72.1 |
| Replace console.log with structured logging | refactoring | 53.5 |
| Add i18n with locale routing to Next.js app | full-stack | 67.7 |
| Build codebase indexer for LLM context windows | from-scratch | 44.4 |
| Write Kubernetes manifests for Node.js microservice | full-stack | 91.3 |
| Build production website with auth and members area | frontend | 66.0 |
| Build SaaS admin dashboard from scratch | from-scratch | 67.7 |
| Implement background job scheduler with persistence | backend | 56.1 |
| Build MCP server for database management | backend | 83.0 |
| Implement transformer inference engine with KV cache | from-scratch | 51.5 |
| Build CLI tool with subcommands and config | from-scratch | 67.0 |
| Fix hallucination and context window bugs in RAG agent | backend | 71.5 |
| Build real-time portfolio risk calculator | backend | 59.1 |
| Build LLM evaluation harness with structured grading | backend | 48.0 |
| Build materialized view refresh pipeline for analytics | backend | 66.5 |
| Fix race conditions in order matching engine | backend | 70.7 |
| Fix data integrity bugs in denormalized e-commerce schema | debugging | 68.5 |
| Write complex SQL report with window functions | backend | 69.7 |
| Debug and fix 6 broken database triggers and constraints | debugging | 79.5 |
| Fix deadlocking transaction patterns in Flask app | backend | 66.8 |
| Find and fix 4 hidden backdoors in Flask app | debugging | 93.3 |
| Add Redis caching layer to Express API | backend | 74.9 |
| Write tests for untested legacy Flask service | code-review | 69.5 |
| Optimize slow Postgres queries in Flask app | backend | 80.2 |
| Add slash commands and moderation to Discord bot | backend | 72.4 |
| Fix 12 WCAG accessibility violations in checkout form | frontend | 81.0 |
| Add retry logic and dead letter queue to Python task queue | backend | 72.5 |
| Add virtual scrolling to table rendering 5000 rows | frontend | 69.0 |
| Fix Node.js stream backpressure causing OOM on large files | backend | 74.7 |
| Build distributed node cluster with gossip protocol | from-scratch | 55.6 |
| Fix auth bypass vulnerability | debugging | 84.0 |
| Write integration tests for payment flow | code-review | 36.8 |
| Add GraphQL layer over REST API | multi-language | 67.2 |
| Add rate limiting middleware | backend | 65.6 |
| Implement Stripe webhook handler | backend | 44.6 |
| Zero-downtime schema migration | full-stack | 61.0 |
| Fix flaky test suite | debugging | 64.5 |
| Refactor monolithic handler to CQRS | refactoring | 73.5 |
| Add cursor-based pagination to REST API | backend | 62.4 |
| Code review: identify security vulns | code-review | 74.9 |
| Fix N+1 query in dashboard | backend | 74.5 |
| Fix memory leak in event handler | debugging | 58.8 |
| Debug race condition in worker pool | debugging | 86.9 |
| Build terminal UI dashboard | from-scratch | 50.3 |
| Fix React hydration mismatch | frontend | 73.5 |
| Build REST API from scratch | from-scratch | 84.6 |