git:20260907.57a4b90 to git:20260911.16cf003

62 added, 139 removed. Audit A to A.

---

name: fullstack-expert

- description: "Expert-level fullstack development guide covering multi-language (TypeScript, Python, Go, Rust), multi-framework (Next.js, FastAPI, Gin, Axum), API design, microservices, DevOps, and system design / Panduan fullstack tingkat ahli mencakup multi-bahasa (TypeScript, Python, Go, Rust), multi-framework (Next.js, FastAPI, Gin, Axum), desain API, microservices, DevOps, dan system design."

+ description: "Expert-level fullstack development guide covering multi-language (TypeScript, Python, Go, Rust), API design (OpenAPI 3.1, gRPC), microservices, system design patterns, and polyglot architecture / Panduan fullstack tingkat ahli mencakup multi-bahasa, desain API, microservices, dan arsitektur polyglot."

author: "Roedy Rustam"

---

- # Fullstack Expert (2026 Multi-Language Edition)

+ # Fullstack Expert (2026 Polyglot & Systems Edition)

[English](#english) | [Bahasa Indonesia](#bahasa-indonesia)

---

## English

### Orchestration & Integration

- Connects and orchestrates with relevant domain skills like `brainstorming`, `zero-to-prod-orchestrator`, and `project-context-mapper` to ensure cohesive execution.

+ Connects and orchestrates with domain skills like `brainstorming`, `zero-to-prod-orchestrator`, `senior-frontend`, `js-backend-expert`, `go-programming-expert`, `python-programming-expert`, and `rust-programming-expert`.

### Description

- Expert-level fullstack development across multiple languages and frameworks. Covers tech stack selection, API design (REST/gRPC/GraphQL), microservice architecture, DevOps, system design patterns, and AI-native backend integration for 2026.

+ Expert-level fullstack development across multiple languages and frameworks. Focuses on polyglot backend architectures, system design patterns (Event-Driven Saga, CQRS), API contracts (OpenAPI 3.1, gRPC), and monorepo shared types.

### Trigger Conditions

- - Choosing the right language and framework for a new service or feature.

- - Designing APIs between services in a multi-language architecture.

- - Planning a microservices decomposition strategy.

- - Implementing system design patterns (event sourcing, CQRS, saga pattern).

- - Integrating AI agents or LLM capabilities into a backend system.

+ - Choosing the right language and framework for a multi-service architecture.

+ - Designing API contracts (REST, gRPC, Hono RPC) between heterogeneous services.

+ - Implementing distributed system design patterns (Saga, CQRS).

+ - Setting up a polyglot monorepo with shared types across frontend and backend.

- ### 2026 Technology Matrix

+ ---

- #### Frontend

- | Tool | Version | Notes |

- |---|---|---|

- | React | 19.x | Compiler, Server Actions, `use()` hook |

- | Next.js | 15.x | PPR, RSC, App Router stable |

- | Astro | 5.x | Islands architecture, MDX, SSG |

- | TanStack Router | 1.x | Type-safe SPA routing |

- | TanStack Start | Beta | Full-stack Vite + RSC patterns |

- | Nuxt | 4.x | Vue 3 SSR/SSG, stable |

- | SvelteKit | 2.x | Lightweight, edge-ready |

+ ### 2026 Polyglot Architecture Matrix

- #### Backend

- | Language | Framework | Best For |

+ > For comprehensive frontend UI architecture, see `senior-frontend` and `nextjs-app-router-expert`.

+ > For dedicated AI agent workflows and LLM integrations, see `ai-llm-integration-expert` and `multi-agent-orchestration`.

+ | Language | Primary Frameworks | Ideal Workloads |

|---|---|---|

- | TypeScript | Hono, Fastify 5, NestJS | Serverless, edge, type-safe RPC |

- | Python | FastAPI 0.115+, Django 5 | AI/ML workloads, data pipelines |

- | Go | net/http (1.22+), Gin, Echo | High-throughput microservices, CLI |

- | Rust | Axum 0.8, Actix-web 4 | Performance-critical, WASM |

+ | **TypeScript** | Hono, Fastify 5, NestJS | Serverless, Edge APIs, type-safe RPC |

+ | **Python** | FastAPI 0.115+, Django 5 | Data science, LLM orchestration, async queues |

+ | **Go** | net/http (Go 1.25+), Gin, Echo | Ultra-high throughput microservices, networking, CLIs |

+ | **Rust** | Axum 0.8, Actix-web 4 | High-performance compute, memory safety, WASM |

- #### AI & Agents

- | Tool | Role |

- |---|---|

- | Vercel AI SDK 5.x | Full-stack AI streaming, RSC |

- | Mastra.ai | TS-first agent framework |

- | LangGraph | Python stateful agent workflows |

- | OpenAI Agents SDK | GPT-5 native agents + handoffs |

- | Google ADK | Gemini-powered agents |

- | Mem0 / MemGPT | Long-term agent memory |

+ #### Infrastructure & Multi-Service Storage

+ - **Primary OLTP**: PostgreSQL with connection pooling (PgBouncer / Supavisor).

+ - **Analytics OLAP**: ClickHouse / DuckDB for high-speed aggregations.

+ - **Cache & Ephemeral State**: Redis / Upstash with TTL.

+ - **Vector Search**: pgvector or Qdrant for semantic search.

- #### Infrastructure

- | Category | Tools |

- |---|---|

- | Container | Docker, Podman |

- | Orchestration | Kubernetes, Railway, Fly.io |

- | CI/CD | GitHub Actions, Turborepo |

- | Observability | OpenTelemetry 1.x, Grafana, Langfuse |

- | Databases | PostgreSQL (primary), ClickHouse (analytics), Redis (cache), Qdrant (vector) |

+ ---

### API Design Standards

#### REST — OpenAPI 3.1

```yaml

- # openapi.yaml

openapi: "3.1.0"

info:

- title: "My SaaS API"

+ title: "SaaS Multi-Service API"

version: "1.0.0"

paths:

/api/v1/workspaces/{id}:

get:

summary: "Get workspace by ID"

parameters:

- name: id

in: path

required: true

schema: { type: string, format: uuid }

responses:

"200":

content:

application/json:

schema: { $ref: "#/components/schemas/Workspace" }

"404":

content:

application/json:

schema: { $ref: "#/components/schemas/ProblemDetail" }

```

- #### gRPC — Protocol Buffers

+ #### gRPC — Protocol Buffers (`proto3`)

```protobuf

syntax = "proto3";

package user.v1;

service UserService {

rpc GetUser (GetUserRequest) returns (User);

- rpc ListUsers (ListUsersRequest) returns (stream User); // Server streaming

+ rpc ListUsers (ListUsersRequest) returns (stream User);

rpc CreateUser (CreateUserRequest) returns (User);

}

message User {

string id = 1;

string email = 2;

string name = 3;

repeated string workspace_ids = 4;

}

```

+ ---

### Microservice Patterns

- #### Event-Driven (Saga Pattern)

+ #### Event-Driven (Saga Pattern with Compensations)

```

Order Service ──publishes──> "order.created" ──> Payment Service

│

┌──────┴──────┐

success? failure?

- │ │

- "payment.succeeded" "payment.failed"

- │ │

- Inventory Service Order Service

- (reserve stock) (cancel order)

+ │ │

+ "payment.succeeded" "payment.failed"

+ │ │

+ Inventory Service Order Service

+ (reserve stock) (cancel order)

```

#### CQRS (Command Query Responsibility Segregation)

- - **Write side**: Commands update the primary PostgreSQL database.

- - **Read side**: Events are projected into read-optimized views (denormalized tables or ClickHouse).

- - Use when read patterns are very different from write patterns.

+ - **Write side**: Commands validate and update the primary relational database.

+ - **Read side**: Events project into read-optimized denormalized views or ClickHouse tables for high-frequency queries.

- ### AI-Native Backend Integration (2026)

+ ---

+ ### AI-Native Backend Integration

```typescript

- // Pattern: AI as a service within existing API

import { generateObject } from 'ai';

import { anthropic } from '@ai-sdk/anthropic';

import { z } from 'zod';

- // AI endpoint that returns structured data

app.post('/api/analyze', async (c) => {

const { content } = await c.req.json();

const { object } = await generateObject({

- model: anthropic('claude-4-sonnet'),

+ model: anthropic('claude-3-7-sonnet-20250219'),

schema: z.object({

sentiment: z.enum(['positive', 'neutral', 'negative']),

topics: z.array(z.string()),

summary: z.string().max(200),

}),

- prompt: `Analyze this content: ${content}`,

+ prompt: `Analyze: ${content}`,

});

return c.json(object);

});

```

- ### SPA vs SSR vs Static — Decision Guide

- ```

- SEO-critical + mostly read? → Next.js SSR / Astro 5 (static)

- Highly interactive dashboard? → SPA (TanStack Start / Vite + TanStack Router)

- → see spa-orchestrator skill for architecture details

- Mixed (marketing + app)? → Next.js 15 with hybrid routing

- Real-time data? → SSR + WebSocket or SSE streaming

- ```

+ ---

### Monorepo with Shared Types

```typescript

// packages/types/src/index.ts — single source of truth

export interface User {

id: string;

email: string;

name: string;

plan: 'free' | 'pro' | 'enterprise';

isSuperAdmin: boolean;

}

- // apps/api & apps/web use the same type

- import type { User } from '@myapp/types';

```

- ### Security Checklist (Fullstack)

- - [ ] All user inputs validated with Zod on the server.

- - [ ] JWT secrets rotated every 90 days; use short expiry + refresh tokens.

- - [ ] CSP headers configured (no `unsafe-inline` in production).

- - [ ] All DB queries use parameterized queries.

- - [ ] Rate limiting on all public API endpoints.

- - [ ] Super Admin routes restricted to `admin.domain.com` with `isSuperAdmin` check.

+ ### Production Security Checklist

+ - [ ] User inputs validated with Zod / Pydantic on the server.

+ - [ ] Parameterized queries enforced across all database layers.

+ - [ ] Rate limiting on all public endpoints (`rate-limit-abuse-prevention`).

+ - [ ] Super Admin routes strictly isolated to dedicated subdomain.

- ### Code Review Standards

- - Functions < 30 lines; files < 300 lines.

- - No business logic in UI components.

- - Every PR includes relevant tests (unit or E2E).

- - No `any` types in TypeScript production code.

- - Dependencies audited with `pnpm audit` on every PR.

+ ## Orchestration & Integration

+ - Integrates with: `js-backend-expert`, `go-programming-expert`, `python-programming-expert`, `rust-programming-expert`, `nextjs-app-router-expert`, `api-design-expert`.

---

## Bahasa Indonesia

- ### Integrasi Orkestrasi

- Terhubung dan mengorkestrasi skill domain yang relevan seperti `brainstorming`, `zero-to-prod-orchestrator`, dan `project-context-mapper` untuk memastikan eksekusi yang kohesif.

### Deskripsi

- Panduan pengembangan fullstack tingkat ahli di berbagai bahasa dan framework. Mencakup pemilihan tech stack, desain API (REST/gRPC/GraphQL), arsitektur microservice, DevOps, pola desain sistem, dan integrasi backend AI-native untuk 2026.

- ### Kondisi Pemicu

- - Memilih bahasa dan framework yang tepat untuk layanan atau fitur baru.

- - Merancang API antar layanan dalam arsitektur multi-bahasa.

- - Merencanakan strategi dekomposisi microservice.

- - Mengimplementasikan pola desain sistem (event sourcing, CQRS, saga pattern).

- - Mengintegrasikan agen AI atau kemampuan LLM ke dalam sistem backend.

- ### Matriks Teknologi 2026

- #### Frontend

- React 19 + Next.js 15 (default SaaS), Astro 5 (konten), TanStack Router (SPA), Nuxt 4 (Vue), SvelteKit 2.

- #### Backend

- TypeScript/Hono (serverless, edge), Python/FastAPI (AI/ML), Go/net/http (throughput tinggi), Rust/Axum (kritis performa).

- #### AI & Agen

- Vercel AI SDK 5.x, Mastra.ai, LangGraph, OpenAI Agents SDK, Google ADK, Mem0/MemGPT untuk memori agen jangka panjang.

- #### Infrastruktur

- Docker/Kubernetes, GitHub Actions + Turborepo, OpenTelemetry 1.x, Langfuse. Database: PostgreSQL (utama), ClickHouse (analitik), Redis (cache), Qdrant (vektor).

- ### Standar Desain API

- - **REST + OpenAPI 3.1**: Untuk API publik dengan beberapa konsumen.

- - **gRPC**: Untuk komunikasi antar layanan internal berkinerja tinggi.

- - **Hono RPC / tRPC**: Untuk komunikasi full-stack TypeScript type-safe tanpa codegen.

- ### Pola Microservice

- #### Event-Driven (Saga Pattern)

- Orkestrasi transaksi terdistribusi melalui event — setiap layanan mempublikasikan event setelah berhasil; kegagalan memicu kompensasi di seluruh rantai.

- #### CQRS

- Pisahkan sisi tulis (PostgreSQL) dari sisi baca (view terdenormalisasi atau ClickHouse) ketika pola baca sangat berbeda dari pola tulis.

- ### Integrasi Backend AI-Native (2026)

- Gunakan Vercel AI SDK `generateObject()` dengan skema Zod untuk mengintegrasikan kemampuan AI ke endpoint API yang ada — mengembalikan output terstruktur yang dijamin sesuai tipe.

+ Panduan pengembangan fullstack tingkat ahli multi-bahasa (TypeScript, Python, Go, Rust), desain kontrak API (OpenAPI 3.1, gRPC), pola arsitektur microservices (Saga, CQRS), dan monorepo shared types.

- ### SPA vs SSR vs Static

- Gunakan SSR/Astro untuk situs kritis SEO dan banyak baca. Gunakan SPA (TanStack Start) untuk dashboard yang sangat interaktif. Gunakan Next.js 15 dengan routing hybrid untuk aplikasi campuran (marketing + app).

+ ### Matriks Arsitektur Polyglot 2026

+ - **TypeScript**: Hono, Fastify 5, NestJS (Serverless, Cloudflare Edge, Hono RPC).

+ - **Python**: FastAPI 0.115+, Django 5 (AI/ML, orkestrasi LLM, pipeline asinkron).

+ - **Go**: net/http (Go 1.25+), Gin (Microservices throughput tinggi, CLI).

+ - **Rust**: Axum 0.8, Actix-web 4 (Performa ekstrem, komputasi berat, WASM).

- ### Monorepo dengan Shared Types

- Definisikan interface dan tipe bersama di `packages/types` — digunakan oleh semua app (web, admin, api, mobile) sebagai single source of truth.

+ ### Pola Sistem Terdistribusi

+ 1. **Saga Pattern**: Kompensasi rollback bertahap saat transaksi multi-layanan mengalami kegagalan.

+ 2. **CQRS**: Memisahkan database tulis (PostgreSQL) dari view proyeksi baca (ClickHouse/Redis) untuk beban baca tinggi.

+ 3. **Monorepo Shared Types**: Simpan definisi tipe bersama di `packages/types` sebagai single source of truth antara frontend dan backend.

- ### Checklist Keamanan & Code Review

- - Input pengguna divalidasi Zod di server.

- - Header CSP dikonfigurasi & parameterized query untuk DB.

- - Rate limiting di semua endpoint publik.

- - Rute Super Admin dibatasi di subdomain dengan cek `isSuperAdmin`.

- - Tidak ada logika bisnis di komponen UI; wajib ada unit/E2E test pada PR.

- - Tidak ada tipe `any` pada kode TypeScript produksi.

+ ## Integrasi Orkestrasi

+ - Terintegrasi dengan: `js-backend-expert`, `go-programming-expert`, `python-programming-expert`, `rust-programming-expert`, `nextjs-app-router-expert`, `api-design-expert`.