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Claude Sonnet 4.6

Anthropic

200K context<$0.01/M input<$0.01/M output
1839peak 1851

Avg Score

84.2

Avg Cost

$0.24

Score/$

344.7

Runs

65

Win/Loss/Draw

Scoring Dimensions

Score Distribution

Category ELOs

multi-languagehard
3135
code-reviewhard
3008
frontendeasy
2632
refactoringexpert
2599
backendeasy
2506
frontendexpert
2422
from-scratchmedium
2345
frontendhard
2218
from-scratcheasy
2101
from-scratchexpert
2072
refactoring
2027
refactoringmedium
2018
multi-language
2011
from-scratchhard
1999
full-stackmedium
1996
code-review
1982
backendhard
1961
code-reviewmedium
1957
debuggingmedium
1956
from-scratch
1927
backendexpert
1927
multi-languageexpert
1924
debuggingexpert
1892
backend
1864
frontend
1858
full-stack
1837
backendmedium
1759
frontendmedium
1757
full-stackhard
1747
debugging
1698
debugginghard
1583

All Results

TaskCategoryScore
Fix broken GitHub Actions CI pipelinedebugging96.5
Add Redis caching layer to Express APIbackend73.7
Add Google OAuth2 login to Express appfull-stack68.5
Implement Stripe webhook handlerbackend92.5
Add streaming SSE endpoint for LLM chatbackend65.4
Fix hallucination and context window bugs in RAG agentbackend85.7
Implement background job scheduler with persistencebackend81.6
Implement transformer inference engine with KV cachefrom-scratch87.0
Add WebSocket real-time updatesfull-stack81.8
Build real-time portfolio risk calculatorbackend74.8
Add rate limiting middlewarebackend91.8
Build materialized view refresh pipeline for analyticsbackend90.3
Code review: identify security vulnscode-review85.7
Build distributed node cluster with gossip protocolfrom-scratch75.3
Fix data integrity bugs in denormalized e-commerce schemadebugging91.4
Build RAG pipeline with vector searchbackend60.5
Port Python CLI to Rustmulti-language68.5
Write tests for untested legacy Flask servicecode-review86.0
Add retry logic and dead letter queue to Python task queuebackend83.3
Migrate callback-hell Express app to async/awaitrefactoring90.0
Fix flaky test suitedebugging90.0
Implement multi-tenant row-level security in Postgresbackend87.6
Build codebase indexer for LLM context windowsfrom-scratch82.3
Add file upload with S3 presigned URLsbackend75.5
Add i18n with locale routing to Next.js appfull-stack81.6
Implement JWT auth middlewarebackend87.0
Write Kubernetes manifests for Node.js microservicefull-stack90.8
Remove AI slop and over-engineering from codebaserefactoring93.0
Find and patch all OWASP Top 10 vulnerabilitiesdebugging91.6
Implement zero-trust API authentication layerbackend83.7
Optimize bloated React bundle under 500KBfrontend90.7
Replace console.log with structured loggingrefactoring92.8
Split 1100-line god file into proper modulesrefactoring90.1
Add caching layer to eliminate slow SSR page loadsfull-stack94.2
Convert React app to PWA with offline supportfrontend72.7
Dockerize Node.js monorepofull-stack89.2
Fix broken responsive layoutfrontend88.2
Harden insecure Docker setup with 12 vulnerabilitiescode-review95.1
Build SaaS admin dashboard from scratchfrom-scratch75.4
Build terminal UI dashboardfrom-scratch75.2
Build production website with auth and members areafrontend78.2
Build CLI tool with subcommands and configfrom-scratch77.7
Build MCP server for database managementbackend87.0
Build LLM evaluation harness with structured gradingbackend74.4
Fix race conditions in order matching enginebackend89.7
Fix deadlocking transaction patterns in Flask appbackend90.4
Debug and fix 6 broken database triggers and constraintsdebugging83.4
Find and fix 4 hidden backdoors in Flask appdebugging93.7
Write complex SQL report with window functionsbackend84.0
Fix 12 WCAG accessibility violations in checkout formfrontend91.8
Optimize slow Postgres queries in Flask appbackend89.1
Add slash commands and moderation to Discord botbackend79.8
Write integration tests for payment flowcode-review83.5
Add GraphQL layer over REST APImulti-language86.4
Add virtual scrolling to table rendering 5000 rowsfrontend74.4
Fix Node.js stream backpressure causing OOM on large filesbackend91.3
Refactor monolithic handler to CQRSrefactoring82.5
Fix auth bypass vulnerabilitydebugging93.7
Zero-downtime schema migrationfull-stack79.0
Add cursor-based pagination to REST APIbackend80.6
Fix N+1 query in dashboardbackend89.5
Fix memory leak in event handlerdebugging79.3
Fix React hydration mismatchfrontend81.9
Debug race condition in worker pooldebugging80.5
Build REST API from scratchfrom-scratch92.1