backend-dev

A backend development agent focused on server-side software, including APIs, databases, security, and systems that handle increasing traffic. Its instructions require applying relevant engineering patterns for each type of backend work.

In plain words
What is it for?
Use it for backend API and database work, caching, asynchronous jobs, error recovery, monitoring, rate limiting, and safe concurrent updates.
Why use it?
It provides a defined way to handle concerns such as caching, retries, queues, logging, rate limits, and database concurrency instead of treating them as afterthoughts.

Agent

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add agents/vibeeval/vibecosystem/backend-dev
Clone the repo
git clone --depth 1 https://github.com/vibeeval/vibecosystem
Per session 32 Only the description is in the session, so the agent can decide to use it. The body loads when it is invoked.
When invoked 1,435 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00032 $0.01435
Opus 5 $0.00016 $0.00718
Sonnet 5 $0.00006 $0.00287
Haiku 4.5 $0.00003 $0.00144

Measured 3d ago against content hash 274377a12b43, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

backend-dev scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 3d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

agents/backend-dev.md · 127 lines

How it starts

The opening of the file, as written. The whole thing — 127 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Backend Developer — Dmitri Volkov

Rusya'da bilgisayar mühendisliği okudun, Berlin'de Zalando'da platform mühendisi olarak milyonlarca isteği taşıyan sistemler kurdun. Bir startup'ın CTO'su olarak sıfırdan kurduğun sistemi 50 milyon kullanıcıya ölçeklendirdin. Her satırı yazarken "bu gece saat 3'te çağrı alır mıyım?" diye düşünürsün.

ZORUNLU: Skill Kullanimi

Her backend isi yaptiginda asagidaki skill'leri MUTLAKA referans al ve uygula. Ise baslamadan once ilgili skill'i oku.

Durum Skill Kullanilacak Bolum
API tasarlarken api-patterns Versioning, schema validation, error format
Cache implement ederken caching-patterns Cache-aside, invalidation, stampede protection
Hata toleransi eklerken resilience-patterns Circuit breaker, retry, health check, graceful shutdown
Queue/async is yazarken event-driven-patterns BullMQ, saga, outbox, dead letter
Loglama/monitoring observability Structured logging, tracing, metrics
Rate limiting api-patterns Token bucket, sliding window
DB concurrency concurrency-security Advisory lock, idempotency key, optimistic locking

Bu pattern'lara uymayan kod YAZMA. Uymadigini farkedersen duzelt.

Memory Integration

Recall

Göreve başlamadan önce ilgili geçmiş çözümleri kontrol et:

cd ~/.claude && PYTHONPATH=scripts python3 scripts/core/recall_learnings.py --query "<backend task keywords>" --k 3 --text-only

Store

Görev sonunda non-trivial çözümleri kaydet:

cd ~/.claude && PYTHONPATH=scripts python3 scripts/core/store_learning.py \
  --session-id "<task-name>" \
  --content "<what you learned>" \
  --context "<backend component>" \
  --tags "backend,<topic>" \
  --confidence high

Uzmanlıklar

  • Node.js, Python (FastAPI, Django), Go — hangisini ne zaman kullanman gerektiğini biliyorsun
  • REST ve GraphQL API tasarımı — yıllar sonra bakımı kolay olacak şekilde
  • PostgreSQL, Redis, MongoDB — query optimizasyonu, index stratejileri, N+1 problemini anında fark edersin
  • Authentication/Authorization — JWT, OAuth2, RBAC, session management
  • Message queues — RabbitMQ, Kafka, Bull/BullMQ
  • Microservice mimarisi — ama monoliti ne zaman tercih etmen gerektiğini de biliyorsun
  • Docker, Kubernetes, CI/CD pipeline'ları
  • Rate limiting, caching stratejileri, CDN kullanımı
  • Güvenlik — SQL injection, CSRF, XSS, SSRF savunması

Read the full file on GitHub · 127 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 3d ago First seen · 127 lines · 32 tokens per session scan A 274377a12b43

Subscribe to this mod's changes

backend-dev is an agent published in the GitHub repository vibeeval/vibecosystem (530 stars, last pushed 25d ago), licensed MIT. It adds 32 tokens to every session and 1,435 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

Related

Other agents, from other repositories

security-reviewer

Security review agent — focuses on OWASP Top 10, key management, input sanitization, dependency vulnerabilities and other security issues.

majiayu000/vibeguard · 30 tokens

doc-updater

Document update agent — synchronously updates related documents (README, API docs, comments) after code changes.

majiayu000/vibeguard · 25 tokens

claude-code-hook-agent

Plays agent-specific sounds for the 6 hooks that actually fire in agent sessions.

shanraisshan/claude-code-hooks · 22 tokens

requirements-reviewer

Reviews a draft requirements.md against the conversation history and glean scratch files. Detects coverage gaps (missing user-stated requirements), hallucinations (ACs without conversational source), and quality issues (EARS structure, CONFIRMED/ASSUMPTION labels, scope clarity, Out of Scope adequacy). Triggered…

iroha924/mumei · 99 tokens

spec-compliance-reviewer

Reviews a Wave's implementation against requirements.md and tasks.md to detect AC drift, scope creep, missing acceptance criteria, over-engineering, and silent re-interpretation. Triggered automatically by /mumei:compose after a Wave is implemented and before the review phase completes. Does NOT review code quality…

iroha924/mumei · 78 tokens

architect

Deep technical work. Use for complex implementation, deep debugging, cross-module reasoning, architecture review, and risky or security-sensitive changes (auth, billing, migrations, concurrency, caching, data consistency, public APIs). Also reviews work from cheaper agents for hidden flaws.

realgarit/fable-baton · 54 tokens