How do I install the Backend Core skill?

Run npx skillmds@latest add aibot88/backend-core in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Backend Core safe to use?

This skill has not completed SkillMD's automated safety review yet. Independent scanners report: SkillSpector: PASS, Skill Scanner: PASS. Capability flags: makes network calls. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Backend Core?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Backend Core free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Backend Core?

aibot88 (@aibot88) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Backend Core by aibot88 — Agent Skill

Name: Backend Core
Rating: 4.2 (5 reviews)
Author: aibot88

Backend Core

Language-agnostic backend patterns: API design, authentication, security, databases. Use when: designing APIs, implementing auth, securing endpoints, modeling data. Triggers: "api design", "rest api", "graphql", "authentication", "jwt", "oauth", "security", "owasp", "database schema", "migrations", "sql".

aibot88 Updated Sep 9, 2026 3 repo stars

File contents

Backend Core Patterns

Quick Reference

Topic	When to Use	Reference
API Design	REST/GraphQL/gRPC endpoints	api-design.md
Authentication	JWT, OAuth, sessions, magic links	authentication.md
Security	Input validation, OWASP, rate limiting	security.md
Databases	Schema design, migrations, queries	databases.md

API Design Decision Tree

What type of API?
├─ Public API → REST + OpenAPI spec
├─ Internal microservices → gRPC (performance) or REST (simplicity)
├─ Real-time → WebSocket or SSE
└─ Complex queries → GraphQL

Auth Decision Tree

Auth method?
├─ SPA/Mobile → JWT (access + refresh tokens)
├─ Server-rendered → Session cookies
├─ Third-party login → OAuth 2.0 / OIDC
├─ Passwordless → Magic link (email) or WebAuthn
└─ API-to-API → API keys or mTLS

Security Essentials

Always:

Validate all inputs at boundaries
Use parameterized queries (never string concat SQL)
Hash passwords with bcrypt/argon2 (cost ≥ 10)
HTTPS everywhere, HSTS headers
Rate limit auth endpoints

Never:

Store secrets in code or git
Trust client-side validation alone
Log sensitive data (passwords, tokens, PII)
Use MD5/SHA1 for passwords

Database Patterns

Schema design:
├─ Start normalized (3NF)
├─ Denormalize only for proven bottlenecks
├─ Always have created_at, updated_at
├─ Use UUIDs for public IDs, integers for internal FKs
└─ Soft delete (deleted_at) for important data

Anti-patterns

Don't	Do Instead
N+1 queries	Eager load / batch queries
SELECT *	Select only needed columns
No indexes on WHERE/JOIN columns	Add indexes
Storing files in DB	Use object storage (S3, R2)
God objects	Bounded contexts, single responsibility

---name: backend-coredescription: Language-agnostic backend patterns: API design, authentication, security, databases. Use when: designing APIs, implementing auth, securing endpoints, modeling data. Triggers: "api design", "rest api", "graphql", "authentication", "jwt", "oauth", "security", "owasp", "database schema", "migrations", "sql".---# Backend Core Patterns## Quick Reference| Topic | When to Use | Reference ||-------|-------------|-----------|| API Design | REST/GraphQL/gRPC endpoints | [api-design.md](references/api-design.md) || Authentication | JWT, OAuth, sessions, magic links | [authentication.md](references/authentication.md) || Security | Input validation, OWASP, rate limiting | [security.md](references/security.md) || Databases | Schema design, migrations, queries | [databases.md](references/databases.md) |## API Design Decision Tree```What type of API?├─ Public API → REST + OpenAPI spec├─ Internal microservices → gRPC (performance) or REST (simplicity)├─ Real-time → WebSocket or SSE└─ Complex queries → GraphQL```## Auth Decision Tree```Auth method?├─ SPA/Mobile → JWT (access + refresh tokens)├─ Server-rendered → Session cookies├─ Third-party login → OAuth 2.0 / OIDC├─ Passwordless → Magic link (email) or WebAuthn└─ API-to-API → API keys or mTLS```## Security Essentials**Always:**- Validate all inputs at boundaries- Use parameterized queries (never string concat SQL)- Hash passwords with bcrypt/argon2 (cost ≥ 10)- HTTPS everywhere, HSTS headers- Rate limit auth endpoints**Never:**- Store secrets in code or git- Trust client-side validation alone- Log sensitive data (passwords, tokens, PII)- Use MD5/SHA1 for passwords## Database Patterns```Schema design:├─ Start normalized (3NF)├─ Denormalize only for proven bottlenecks├─ Always have created_at, updated_at├─ Use UUIDs for public IDs, integers for internal FKs└─ Soft delete (deleted_at) for important data```## Anti-patterns| Don't | Do Instead ||-------|------------|| N+1 queries | Eager load / batch queries || SELECT * | Select only needed columns || No indexes on WHERE/JOIN columns | Add indexes || Storing files in DB | Use object storage (S3, R2) || God objects | Bounded contexts, single responsibility |

Frequently asked questions