APEX
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Grok 4.1 Fast

OpenRouter

2000K context$0.20/M input$0.50/M output
1570peak 1601

Avg Score

68.3

Avg Cost

$0.05

Score/$

1426.0

Runs

118

Win/Loss/Draw

Scoring Dimensions

Score Distribution

Category ELOs

from-scratchmedium
1870
code-reviewhard
1820
debuggingexpert
1784
from-scratcheasy
1773
debugginghard
1703
multi-languagehard
1680
debugging
1675
debuggingmedium
1647
full-stackhard
1631
frontendhard
1622
backendeasy
1620
frontendexpert
1616
backendexpert
1614
from-scratch
1611
frontendmedium
1600
from-scratchhard
1596
backendhard
1594
backend
1582
backendmedium
1581
frontend
1573
full-stack
1560
frontendeasy
1555
full-stackmedium
1516
code-review
1510
code-reviewmedium
1471
from-scratchexpert
1449
refactoringmedium
1439
refactoring
1433
refactoringexpert
1376
multi-language
1348
multi-languageexpert
327

All Results

TaskCategoryScore
Implement background job scheduler with persistencebackend3.9
Build SaaS admin dashboard from scratchfrom-scratch23.8
Build CLI tool with subcommands and configfrom-scratch6.3
Fix N+1 query in dashboardbackend63.5
Fix flaky test suitedebugging93.2
Debug and fix 6 broken database triggers and constraintsdebugging90.8
Write complex SQL report with window functionsbackend70.5
Find and patch all OWASP Top 10 vulnerabilitiesdebugging69.7
Dockerize Node.js monorepofull-stack71.1
Optimize slow Postgres queries in Flask appbackend82.0
Find and fix 4 hidden backdoors in Flask appdebugging93.5
Add i18n with locale routing to Next.js appfull-stack64.7
Implement JWT auth middlewarebackend45.1
Build real-time portfolio risk calculatorbackend64.0
Code review: identify security vulnscode-review82.9
Fix data integrity bugs in denormalized e-commerce schemadebugging89.3
Write Kubernetes manifests for Node.js microservicefull-stack87.5
Fix React hydration mismatchfrontend78.3
Build terminal UI dashboardfrom-scratch66.3
Write integration tests for payment flowcode-review40.7
Add Google OAuth2 login to Express appfull-stack82.5
Add slash commands and moderation to Discord botbackend63.4
Fix Node.js stream backpressure causing OOM on large filesbackend80.1
Write tests for untested legacy Flask servicecode-review35.0
Build REST API from scratchfrom-scratch60.9
Fix broken GitHub Actions CI pipelinedebugging74.5
Fix hallucination and context window bugs in RAG agentbackend86.4
Add rate limiting middlewarebackend74.0
Build distributed node cluster with gossip protocolfrom-scratch29.0
Implement transformer inference engine with KV cachefrom-scratch70.8
Add Redis caching layer to Express APIbackend62.4
Build materialized view refresh pipeline for analyticsbackend54.5
Port Python CLI to Rustmulti-language41.0
Implement zero-trust API authentication layerbackend32.5
Build MCP server for database managementbackend88.2
Convert React app to PWA with offline supportfrontend71.8
Fix broken responsive layoutfrontend75.3
Replace console.log with structured loggingrefactoring62.7
Fix memory leak in event handlerdebugging75.6
Add WebSocket real-time updatesfull-stack67.3
Add cursor-based pagination to REST APIbackend70.8
Add retry logic and dead letter queue to Python task queuebackend81.3
Build codebase indexer for LLM context windowsfrom-scratch38.2
Build production website with auth and members areafrontend60.5
Fix 12 WCAG accessibility violations in checkout formfrontend74.7
Implement Stripe webhook handlerbackend77.5
Add caching layer to eliminate slow SSR page loadsfull-stack57.1
Add GraphQL layer over REST APImulti-language75.8
Remove AI slop and over-engineering from codebaserefactoring68.9
Add streaming SSE endpoint for LLM chatbackend84.4
Migrate callback-hell Express app to async/awaitrefactoring54.9
Add file upload with S3 presigned URLsbackend82.5
Split 1100-line god file into proper modulesrefactoring58.1
Refactor monolithic handler to CQRSrefactoring57.4
Debug race condition in worker pooldebugging93.7
Build RAG pipeline with vector searchbackend31.4
Fix race conditions in order matching enginebackend78.1
Fix deadlocking transaction patterns in Flask appbackend68.8
Fix auth bypass vulnerabilitydebugging71.7
Implement multi-tenant row-level security in Postgresbackend42.3
Optimize bloated React bundle under 500KBfrontend76.2
Harden insecure Docker setup with 12 vulnerabilitiescode-review77.6
Zero-downtime schema migrationfull-stack73.0
Build LLM evaluation harness with structured gradingbackend79.5
Add virtual scrolling to table rendering 5000 rowsfrontend43.0
Implement JWT auth middlewarebackend75.7
Dockerize Node.js monorepofull-stack30.6
Convert React app to PWA with offline supportfrontend64.7
Write Kubernetes manifests for Node.js microservicefull-stack85.3
Add caching layer to eliminate slow SSR page loadsfull-stack79.3
Build codebase indexer for LLM context windowsfrom-scratch35.0
Implement multi-tenant row-level security in Postgresbackend74.0
Add i18n with locale routing to Next.js appfull-stack62.4
Remove AI slop and over-engineering from codebaserefactoring77.0
Find and patch all OWASP Top 10 vulnerabilitiesdebugging72.0
Split 1100-line god file into proper modulesrefactoring74.2
Harden insecure Docker setup with 12 vulnerabilitiescode-review89.7
Optimize bloated React bundle under 500KBfrontend67.2
Fix broken responsive layoutfrontend72.3
Replace console.log with structured loggingrefactoring51.5
Implement zero-trust API authentication layerbackend71.8
Fix data integrity bugs in denormalized e-commerce schemadebugging71.7
Build MCP server for database managementbackend76.2
Build CLI tool with subcommands and configfrom-scratch40.0
Zero-downtime schema migrationfull-stack84.0
Write complex SQL report with window functionsbackend74.5
Build real-time portfolio risk calculatorbackend64.2
Build distributed node cluster with gossip protocolfrom-scratch74.9
Optimize slow Postgres queries in Flask appbackend76.7
Debug and fix 6 broken database triggers and constraintsdebugging86.7
Build terminal UI dashboardfrom-scratch47.7
Implement background job scheduler with persistencebackend54.0
Build LLM evaluation harness with structured gradingbackend73.6
Add cursor-based pagination to REST APIbackend82.8
Write integration tests for payment flowcode-review69.3
Build REST API from scratchfrom-scratch85.8
Fix hallucination and context window bugs in RAG agentbackend72.9
Find and fix 4 hidden backdoors in Flask appdebugging92.5
Add rate limiting middlewarebackend76.2
Build production website with auth and members areafrontend65.2
Build SaaS admin dashboard from scratchfrom-scratch74.0
Write tests for untested legacy Flask servicecode-review38.8
Fix React hydration mismatchfrontend76.3
Implement Stripe webhook handlerbackend59.5
Add virtual scrolling to table rendering 5000 rowsfrontend78.8
Fix memory leak in event handlerdebugging80.3
Fix Node.js stream backpressure causing OOM on large filesbackend90.8
Fix N+1 query in dashboardbackend75.2
Add slash commands and moderation to Discord botbackend77.5
Fix auth bypass vulnerabilitydebugging92.5
Add retry logic and dead letter queue to Python task queuebackend73.6
Fix flaky test suitedebugging82.8
Fix 12 WCAG accessibility violations in checkout formfrontend82.1
Fix race conditions in order matching enginebackend82.2
Implement transformer inference engine with KV cachefrom-scratch78.2
Debug race condition in worker pooldebugging84.3
Refactor monolithic handler to CQRSrefactoring60.6
Fix deadlocking transaction patterns in Flask appbackend69.2