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Qwen3.5 397b A17b

OpenRouter

262K context$0.60/M input$3.60/M output
1549peak 1558

Avg Score

68.0

Avg Cost

$0.12

Score/$

571.7

Runs

123

Win/Loss/Draw

Scoring Dimensions

Score Distribution

Category ELOs

multi-languagehard
2101
backendeasy
1923
refactoringexpert
1912
from-scratchmedium
1896
code-reviewhard
1842
frontendexpert
1743
frontendhard
1722
debuggingmedium
1703
full-stackhard
1640
full-stackmedium
1636
backendexpert
1626
full-stack
1619
backendhard
1588
backend
1584
debugginghard
1584
frontendmedium
1581
frontend
1574
refactoring
1563
backendmedium
1552
from-scratchhard
1542
debugging
1535
refactoringmedium
1509
code-review
1480
multi-language
1477
from-scratch
1476
debuggingexpert
1448
frontendeasy
1433
code-reviewmedium
1414
from-scratcheasy
1413
multi-languageexpert
1147
from-scratchexpert
0

All Results

TaskCategoryScore
Fix data integrity bugs in denormalized e-commerce schemadebugging49.0
Split 1100-line god file into proper modulesrefactoring42.3
Build REST API from scratchfrom-scratch74.5
Refactor monolithic handler to CQRSrefactoring38.3
Build materialized view refresh pipeline for analyticsbackend72.8
Add cursor-based pagination to REST APIbackend80.5
Implement JWT auth middlewarebackend55.1
Build SaaS admin dashboard from scratchfrom-scratch42.8
Fix memory leak in event handlerdebugging80.1
Build codebase indexer for LLM context windowsfrom-scratch34.5
Add retry logic and dead letter queue to Python task queuebackend83.6
Debug race condition in worker pooldebugging85.3
Fix N+1 query in dashboardbackend53.4
Optimize slow Postgres queries in Flask appbackend85.2
Implement Stripe webhook handlerbackend83.6
Replace console.log with structured loggingrefactoring53.4
Write tests for untested legacy Flask servicecode-review50.7
Convert React app to PWA with offline supportfrontend77.5
Fix 12 WCAG accessibility violations in checkout formfrontend62.6
Implement background job scheduler with persistencebackend54.8
Build CLI tool with subcommands and configfrom-scratch65.3
Add file upload with S3 presigned URLsbackend65.5
Write integration tests for payment flowcode-review80.5
Fix hallucination and context window bugs in RAG agentbackend51.3
Add rate limiting middlewarebackend44.6
Implement multi-tenant row-level security in Postgresbackend43.9
Add Redis caching layer to Express APIbackend81.6
Add Google OAuth2 login to Express appfull-stack78.3
Code review: identify security vulnscode-review34.0
Add slash commands and moderation to Discord botbackend69.6
Zero-downtime schema migrationfull-stack74.2
Implement zero-trust API authentication layerbackend72.1
Fix React hydration mismatchfrontend80.6
Find and patch all OWASP Top 10 vulnerabilitiesdebugging65.9
Add GraphQL layer over REST APImulti-language84.0
Remove AI slop and over-engineering from codebaserefactoring74.8
Build LLM evaluation harness with structured gradingbackend76.3
Find and fix 4 hidden backdoors in Flask appdebugging76.3
Fix race conditions in order matching enginebackend75.7
Write Kubernetes manifests for Node.js microservicefull-stack85.5
Fix broken responsive layoutfrontend62.8
Harden insecure Docker setup with 12 vulnerabilitiescode-review79.0
Build production website with auth and members areafrontend63.5
Fix broken GitHub Actions CI pipelinedebugging84.7
Add virtual scrolling to table rendering 5000 rowsfrontend51.5
Fix deadlocking transaction patterns in Flask appbackend77.4
Dockerize Node.js monorepofull-stack75.7
Build real-time portfolio risk calculatorbackend54.5
Migrate callback-hell Express app to async/awaitrefactoring72.9
Port Python CLI to Rustmulti-language33.6
Optimize bloated React bundle under 500KBfrontend70.8
Fix auth bypass vulnerabilitydebugging89.3
Fix Node.js stream backpressure causing OOM on large filesbackend87.0
Debug and fix 6 broken database triggers and constraintsdebugging60.7
Add caching layer to eliminate slow SSR page loadsfull-stack81.0
Add i18n with locale routing to Next.js appfull-stack72.7
Build RAG pipeline with vector searchbackend40.0
Add WebSocket real-time updatesfull-stack82.4
Build distributed node cluster with gossip protocolfrom-scratch31.9
Build MCP server for database managementbackend82.0
Write complex SQL report with window functionsbackend61.0
Implement transformer inference engine with KV cachefrom-scratch34.8
Add streaming SSE endpoint for LLM chatbackend77.8
Build terminal UI dashboardfrom-scratch40.5
Fix flaky test suitedebugging81.9
Implement zero-trust API authentication layerbackend66.1
Build codebase indexer for LLM context windowsfrom-scratch55.0
Fix broken responsive layoutfrontend72.0
Optimize bloated React bundle under 500KBfrontend73.6
Add caching layer to eliminate slow SSR page loadsfull-stack84.8
Convert React app to PWA with offline supportfrontend71.3
Add streaming SSE endpoint for LLM chatbackend81.8
Remove AI slop and over-engineering from codebaserefactoring81.3
Implement multi-tenant row-level security in Postgresbackend74.5
Dockerize Node.js monorepofull-stack75.6
Replace console.log with structured loggingrefactoring45.6
Find and patch all OWASP Top 10 vulnerabilitiesdebugging68.3
Implement JWT auth middlewarebackend82.4
Split 1100-line god file into proper modulesrefactoring72.5
Add i18n with locale routing to Next.js appfull-stack65.8
Write Kubernetes manifests for Node.js microservicefull-stack85.2
Harden insecure Docker setup with 12 vulnerabilitiescode-review73.8
Build production website with auth and members areafrontend67.7
Build SaaS admin dashboard from scratchfrom-scratch69.8
Build MCP server for database managementbackend80.0
Build CLI tool with subcommands and configfrom-scratch46.0
Implement transformer inference engine with KV cachefrom-scratch42.8
Implement background job scheduler with persistencebackend53.4
Fix hallucination and context window bugs in RAG agentbackend70.4
Build LLM evaluation harness with structured gradingbackend63.1
Build real-time portfolio risk calculatorbackend64.7
Fix race conditions in order matching enginebackend87.1
Build materialized view refresh pipeline for analyticsbackend71.2
Fix data integrity bugs in denormalized e-commerce schemadebugging68.5
Fix deadlocking transaction patterns in Flask appbackend68.4
Write complex SQL report with window functionsbackend81.2
Debug and fix 6 broken database triggers and constraintsdebugging80.5
Write tests for untested legacy Flask servicecode-review56.1
Find and fix 4 hidden backdoors in Flask appdebugging93.3
Add Redis caching layer to Express APIbackend69.5
Optimize slow Postgres queries in Flask appbackend82.8
Add slash commands and moderation to Discord botbackend60.0
Add retry logic and dead letter queue to Python task queuebackend78.7
Fix 12 WCAG accessibility violations in checkout formfrontend84.1
Fix Node.js stream backpressure causing OOM on large filesbackend77.5
Add virtual scrolling to table rendering 5000 rowsfrontend74.0
Write integration tests for payment flowcode-review39.6
Build distributed node cluster with gossip protocolfrom-scratch41.3
Fix auth bypass vulnerabilitydebugging93.7
Add GraphQL layer over REST APImulti-language67.2
Add rate limiting middlewarebackend81.8
Zero-downtime schema migrationfull-stack63.1
Fix flaky test suitedebugging83.5
Build terminal UI dashboardfrom-scratch66.7
Implement Stripe webhook handlerbackend61.0
Refactor monolithic handler to CQRSrefactoring71.2
Add cursor-based pagination to REST APIbackend52.5
Code review: identify security vulnscode-review59.3
Fix N+1 query in dashboardbackend74.5
Fix memory leak in event handlerdebugging58.5
Debug race condition in worker pooldebugging85.7
Fix React hydration mismatchfrontend76.1
Build REST API from scratchfrom-scratch81.1