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Qwen3.5 Plus 02.15

OpenRouter

1000K context$0.40/M input$2.40/M output
1442peak 1531

Avg Score

71.3

Avg Cost

$0.07

Score/$

990.2

Runs

65

Win/Loss/Draw

Scoring Dimensions

Score Distribution

Category ELOs

multi-languageexpert
2259
code-reviewhard
2130
from-scratchmedium
1930
from-scratchexpert
1732
from-scratcheasy
1700
full-stackmedium
1673
full-stack
1578
code-review
1561
backendhard
1555
from-scratch
1551
backendexpert
1548
refactoringexpert
1532
frontendeasy
1529
frontendhard
1516
full-stackhard
1512
from-scratchhard
1504
code-reviewmedium
1495
backend
1492
debuggingmedium
1474
multi-language
1468
refactoring
1457
backendmedium
1444
debuggingexpert
1433
refactoringmedium
1426
debugginghard
1419
debugging
1418
frontend
1406
frontendexpert
1386
frontendmedium
1353
multi-languagehard
925
backendeasy
867

All Results

TaskCategoryScore
Build CLI tool with subcommands and configfrom-scratch75.5
Write integration tests for payment flowcode-review83.8
Build distributed node cluster with gossip protocolfrom-scratch75.0
Fix hallucination and context window bugs in RAG agentbackend83.3
Build real-time portfolio risk calculatorbackend81.7
Port Python CLI to Rustmulti-language76.2
Code review: identify security vulnscode-review75.9
Implement background job scheduler with persistencebackend69.5
Add i18n with locale routing to Next.js appfull-stack62.5
Fix broken GitHub Actions CI pipelinedebugging62.4
Build terminal UI dashboardfrom-scratch74.3
Add streaming SSE endpoint for LLM chatbackend70.8
Fix broken responsive layoutfrontend72.8
Write complex SQL report with window functionsbackend85.7
Write tests for untested legacy Flask servicecode-review65.0
Find and patch all OWASP Top 10 vulnerabilitiesdebugging65.8
Add virtual scrolling to table rendering 5000 rowsfrontend80.0
Fix flaky test suitedebugging90.9
Dockerize Node.js monorepofull-stack75.1
Add Google OAuth2 login to Express appfull-stack75.8
Fix auth bypass vulnerabilitydebugging76.8
Build REST API from scratchfrom-scratch78.3
Implement Stripe webhook handlerbackend76.3
Optimize bloated React bundle under 500KBfrontend69.6
Build RAG pipeline with vector searchbackend50.9
Fix 12 WCAG accessibility violations in checkout formfrontend80.7
Refactor monolithic handler to CQRSrefactoring60.8
Add WebSocket real-time updatesfull-stack85.6
Fix N+1 query in dashboardbackend83.3
Find and fix 4 hidden backdoors in Flask appdebugging87.0
Fix Node.js stream backpressure causing OOM on large filesbackend65.3
Build materialized view refresh pipeline for analyticsbackend85.6
Build LLM evaluation harness with structured gradingbackend52.5
Optimize slow Postgres queries in Flask appbackend77.7
Add file upload with S3 presigned URLsbackend74.1
Debug race condition in worker pooldebugging82.3
Build SaaS admin dashboard from scratchfrom-scratch44.3
Fix memory leak in event handlerdebugging49.3
Build production website with auth and members areafrontend60.5
Add rate limiting middlewarebackend66.3
Fix deadlocking transaction patterns in Flask appbackend83.1
Implement zero-trust API authentication layerbackend74.1
Migrate callback-hell Express app to async/awaitrefactoring74.1
Split 1100-line god file into proper modulesrefactoring74.8
Replace console.log with structured loggingrefactoring55.5
Add cursor-based pagination to REST APIbackend46.6
Fix React hydration mismatchfrontend53.9
Harden insecure Docker setup with 12 vulnerabilitiescode-review79.0
Add slash commands and moderation to Discord botbackend65.8
Convert React app to PWA with offline supportfrontend77.3
Implement multi-tenant row-level security in Postgresbackend45.5
Debug and fix 6 broken database triggers and constraintsdebugging65.1
Write Kubernetes manifests for Node.js microservicefull-stack82.6
Build MCP server for database managementbackend78.5
Add Redis caching layer to Express APIbackend53.9
Fix data integrity bugs in denormalized e-commerce schemadebugging81.7
Add retry logic and dead letter queue to Python task queuebackend79.7
Implement transformer inference engine with KV cachefrom-scratch81.7
Remove AI slop and over-engineering from codebaserefactoring85.0
Implement JWT auth middlewarebackend55.0
Add GraphQL layer over REST APImulti-language53.6
Add caching layer to eliminate slow SSR page loadsfull-stack82.7
Build codebase indexer for LLM context windowsfrom-scratch46.0
Fix race conditions in order matching enginebackend79.5
Zero-downtime schema migrationfull-stack72.6