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GPT 5.5
OpenAI
400K context$5.00/M input$30.00/M output
1866peak 1867
Avg Score
86.8
Avg Cost
$1.61
Score/$
53.7
Runs
70
Win/Loss/Draw
Scoring Dimensions
Score Distribution
Category ELOs
multi-languageexpert
3114code-reviewhard
2756frontendeasy
2671from-scratchmedium
2639multi-languagehard
2415frontendexpert
2395backendeasy
2290from-scratchhard
2271frontendhard
2255from-scratcheasy
2215multi-language
2121code-review
2116code-reviewmedium
2109from-scratchexpert
2075from-scratch
2023backendexpert
2009frontendmedium
2006refactoringmedium
1986backendhard
1960full-stackmedium
1958frontend
1923full-stackhard
1922full-stack
1921backend
1877refactoring
1850debuggingexpert
1815backendmedium
1791debuggingmedium
1775backendmaster
1762refactoringexpert
1752debugging
1695debugginghard
1633frontendmaster
1588All Results
| Task | Category | Score |
|---|---|---|
| Build multi-tool LLM agent runtime | backend | 86.0 |
| Build interactive data visualization dashboard | frontend | 65.2 |
| Migrate Express monolith to modular architecture | backend | 83.0 |
| Fix and extend Chrome browser extension | frontend | 67.0 |
| Build 3D browser game with physics and multiplayer sync | frontend | 87.1 |
| Convert React app to PWA with offline support | frontend | 87.0 |
| Add virtual scrolling to table rendering 5000 rows | frontend | 89.7 |
| Build REST API from scratch | from-scratch | 89.7 |
| Debug and fix 6 broken database triggers and constraints | debugging | 90.4 |
| Remove AI slop and over-engineering from codebase | refactoring | 91.8 |
| Add streaming SSE endpoint for LLM chat | backend | 87.5 |
| Fix 12 WCAG accessibility violations in checkout form | frontend | 91.3 |
| Find and patch all OWASP Top 10 vulnerabilities | debugging | 91.3 |
| Add slash commands and moderation to Discord bot | backend | 86.0 |
| Split 1100-line god file into proper modules | refactoring | 88.5 |
| Build terminal UI dashboard | from-scratch | 82.5 |
| Refactor monolithic handler to CQRS | refactoring | 69.3 |
| Build CLI tool with subcommands and config | from-scratch | 87.2 |
| Find and fix 4 hidden backdoors in Flask app | debugging | 77.3 |
| Debug race condition in worker pool | debugging | 93.0 |
| Fix React hydration mismatch | frontend | 87.0 |
| Replace console.log with structured logging | refactoring | 91.8 |
| Add caching layer to eliminate slow SSR page loads | full-stack | 91.8 |
| Add file upload with S3 presigned URLs | backend | 85.3 |
| Build MCP server for database management | backend | 90.9 |
| Add i18n with locale routing to Next.js app | full-stack | 82.4 |
| Add retry logic and dead letter queue to Python task queue | backend | 88.9 |
| Build RAG pipeline with vector search | backend | 83.7 |
| Fix race conditions in order matching engine | backend | 90.5 |
| Fix broken GitHub Actions CI pipeline | debugging | 89.5 |
| Add Redis caching layer to Express API | backend | 84.1 |
| Build production website with auth and members area | frontend | 80.7 |
| Build distributed node cluster with gossip protocol | from-scratch | 87.7 |
| Build materialized view refresh pipeline for analytics | backend | 86.0 |
| Implement transformer inference engine with KV cache | from-scratch | 85.8 |
| Build codebase indexer for LLM context windows | from-scratch | 81.8 |
| Implement zero-trust API authentication layer | backend | 90.7 |
| Implement JWT auth middleware | backend | 64.0 |
| Build real-time portfolio risk calculator | backend | 84.0 |
| Add Google OAuth2 login to Express app | full-stack | 87.2 |
| Write Kubernetes manifests for Node.js microservice | full-stack | 91.8 |
| Fix data integrity bugs in denormalized e-commerce schema | debugging | 85.6 |
| Implement Stripe webhook handler | backend | 88.0 |
| Add cursor-based pagination to REST API | backend | 87.7 |
| Optimize slow Postgres queries in Flask app | backend | 89.8 |
| Fix hallucination and context window bugs in RAG agent | backend | 85.8 |
| Fix deadlocking transaction patterns in Flask app | backend | 86.0 |
| Build SaaS admin dashboard from scratch | from-scratch | 86.5 |
| Fix flaky test suite | debugging | 89.5 |
| Fix N+1 query in dashboard | backend | 91.7 |
| Harden insecure Docker setup with 12 vulnerabilities | code-review | 94.6 |
| Add rate limiting middleware | backend | 86.8 |
| Write integration tests for payment flow | code-review | 93.2 |
| Build LLM evaluation harness with structured grading | backend | 87.2 |
| Write complex SQL report with window functions | backend | 88.9 |
| Fix Node.js stream backpressure causing OOM on large files | backend | 94.1 |
| Fix broken responsive layout | frontend | 91.7 |
| Zero-downtime schema migration | full-stack | 86.4 |
| Fix auth bypass vulnerability | debugging | 93.7 |
| Optimize bloated React bundle under 500KB | frontend | 91.7 |
| Port Python CLI to Rust | multi-language | 85.8 |
| Write tests for untested legacy Flask service | code-review | 89.3 |
| Fix memory leak in event handler | debugging | 91.7 |
| Add WebSocket real-time updates | full-stack | 89.3 |
| Add GraphQL layer over REST API | multi-language | 89.7 |
| Code review: identify security vulns | code-review | 91.8 |
| Implement multi-tenant row-level security in Postgres | backend | 85.7 |
| Implement background job scheduler with persistence | backend | 84.1 |
| Dockerize Node.js monorepo | full-stack | 83.8 |
| Migrate callback-hell Express app to async/await | refactoring | 87.2 |