# Backend Mindset

> Guides backend development across API design, authentication, databases, performance, security, scalability, and testing, with quick decision guides and defaults for production-ready systems.

- Skill: `dangquangse/backend-mindset` (Agent Skill, multi-file: 9 files)
- Install (CLI): `npx skillmds@latest add dangquangse/backend-mindset`
- Raw SKILL.md: https://api.skillmd.com/api/skills/dangquangse/backend-mindset/raw
- Safety review: PASS (external: skill-scanner PASS, skillspector PASS)
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools, DevOps & Infra, Security, API Design, Secure Coding, Testing & QA
- Tags: Api Design, Authentication, Backend, Graphql, Grpc, Jwt, Oauth, Rest
- License: MIT
- Author: DangQuangSE (https://skillmd.com/u/dangquangse)
- Updated: 2026-08-22
- Page: https://skillmd.com/skills/dangquangse/backend-mindset

---


# Backend Development Skill

## References

| File | Covers |
|------|--------|
| `.codex/skills/backend-mindset/references/api-design.md` | REST, GraphQL, gRPC — URL rules, status codes, protocol selection |
| `.codex/skills/backend-mindset/references/authentication.md` | OAuth 2.1, JWT, RBAC, MFA, session management |
| `.codex/skills/backend-mindset/references/security.md` | OWASP Top 10 (2025), rate limiting, headers, secrets |
| `.codex/skills/backend-mindset/references/performance.md` | Indexing, caching patterns, load balancing, async processing |
| `.codex/skills/backend-mindset/references/architecture.md` | Microservices patterns, event-driven, CQRS, scalability |
| `.codex/skills/backend-mindset/references/testing.md` | TDD, test pyramid, contract testing, migration tests |
| `.codex/skills/backend-mindset/references/code-quality.md` | SOLID, design patterns, refactoring signals |

## Quick Decision Guide

| Need | Choose |
|------|--------|
| Public / browser clients | REST or GraphQL |
| Internal high-throughput | gRPC |
| Flexible data fetching | GraphQL |
| Streaming | gRPC (bidirectional) or SSE |
| Single team, unclear domain | Monolith |
| Multiple autonomous teams | Microservices |
| Audit trail required | Event Sourcing |
| Read/write load imbalance | CQRS |
| Task >200ms off request path | Async queue |
| Session across instances | Redis (never in-process) |

## Defaults

- Every non-public endpoint requires explicit auth declaration — no implicit defaults
- Input validation at every system boundary (API handler, event consumer, file parser)
- Parameterized queries everywhere — never string-interpolate user input
- Rate limiting on auth endpoints, public API, and file upload (see security.md for thresholds)
- Integration tests hit real infrastructure (Testcontainers) — in-memory substitutes hide real bugs
- TDD: write the failing test before any implementation
- Services return result envelopes — never throw for expected failures (404, 400, 409)