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Qwen3.5 Plus 02.15

OpenRouter

1000K context$0.40/M input$2.40/M output
1482peak 1499

Avg Score

71.3

Avg Cost

$0.07

Score/$

990.2

Runs

65

Win/Loss/Draw

Scoring Dimensions

Score Distribution

Category ELOs

multi-languageexpert
2331
code-reviewhard
2219
from-scratchmedium
2111
from-scratchexpert
1783
refactoringexpert
1757
frontendhard
1632
backendhard
1552
code-review
1547
refactoring
1533
from-scratch
1523
full-stackmedium
1515
full-stack
1511
refactoringmedium
1508
backendexpert
1507
full-stackhard
1504
multi-language
1501
backend
1491
debuggingmedium
1480
frontendeasy
1476
from-scratchhard
1467
backendmedium
1462
code-reviewmedium
1460
frontend
1420
frontendmedium
1412
debugginghard
1397
debugging
1394
from-scratcheasy
1368
debuggingexpert
1354
backendeasy
1129
frontendexpert
1114
multi-languagehard
1052

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