Prompt Engineering aplicado a Dev
Prompt Engineering Dev
🧠 Lesson: Prompt Engineering for Developers (AI-Native)
🎯 Objective
Learn how to design, structure, and optimize prompts to build real software faster using AI—across frontend, backend, testing, and deployment.
🚀 1. What is Prompt Engineering (in Development)?
Prompt engineering is the skill of communicating with AI to produce reliable, production-ready outputs.
👉 For developers, this means:
Generating clean code
Designing architectures
Writing tests
Debugging faster
Automating workflows
You are not just coding—you are orchestrating AI to code with you.
🧠 2. The Core Principle
Bad prompt → random output
Good prompt → structured, usable solution
👉 The quality of your prompt = the quality of your system
🧩 3. The Developer Prompt Framework
Use this structure for almost everything:
🧱
1. Role
Tell the AI who it is
“You are a senior full-stack developer using React and NestJS”
📌
2. Context
Provide system details
Stack, architecture, constraints, business goal
🎯
3. Task
Be explicit
“Create a login API with JWT authentication”
📋
4. Constraints
Define rules
Use TypeScript
Follow clean architecture
Use DTOs and validation
📤
5. Output Format
Control the response
“Return code only, separated by files”
✅ Example (GOOD prompt)
You are a senior NestJS developer.
Context:
I am building a SaaS application with authentication.
Task:
Create a login endpoint using JWT.
Constraints:
- Use NestJS best practices
- Use DTO validation
- Include error handling
Output:
Return the controller, service, and DTO files separately.⚙️ 4. Prompting Across the Dev Workflow
💻 1. Code Generation
Components (React)
APIs (NestJS)
Database schemas
👉 Tip: Always specify structure + patterns
🧪 2. Testing (TDD + E2E)
Prompt example:
“Generate unit tests for this service using Jest, covering edge cases”
👉 AI can:
Create tests
Suggest missing cases
Improve coverage
🐛 3. Debugging
Prompt example:
“Explain why this code fails and suggest a fix with minimal changes”
👉 Add:
Error logs
Stack traces
Code snippet
🔁 4. Refactoring
Prompt example:
“Refactor this code to follow clean architecture and improve readability”
📦 5. Architecture Design
Prompt example:
“Design a scalable architecture for a multi-tenant SaaS using NestJS and PostgreSQL”
🧠 5. Advanced Prompting Techniques
🔁 Iterative Prompting
Don’t expect perfection in one shot:
Generate
Review
Refine
Improve
🧩 Chain of Thought (Guided Thinking)
Ask AI to reason step-by-step:
“Explain your approach before writing the code”
🧠 Context Injection
Provide:
Existing code
Project structure
Business rules
👉 More context = better output
🎭 Role-Based Prompting
Assign expertise:
“Senior frontend engineer”
“DevOps expert”
“QA engineer”
🧰 6. Tools That Amplify Prompt Engineering
💻 Development
AI copilots (IDE integration)
Chat-based coding assistants
🎥 Content / Product
ElevenLabs
HeyGen
Nano Banana
👉 Prompt engineering applies beyond code → also marketing, demos, and content
⚠️ 7. Common Mistakes
❌ Vague prompts → “Create an app”
❌ No constraints → messy code
❌ No output format → unusable results
❌ Blind trust in AI
❌ No iteration
🧪 8. Practical Exercise
🛠️ Task:
Build a feature using prompts only
Feature: User registration
Prompt AI to generate:
Backend API (NestJS)
Frontend form (React)
Validation
Tests
Improve your prompts until:
Code is clean
Works correctly
Follows best practices
Compare:
First prompt vs final prompt
🧩 9. Prompt Templates (Reusable)
🔹 Generate API
You are a senior backend developer.
Create a [feature] using NestJS.
Constraints:
- Use TypeScript
- Follow clean architecture
- Include validation and error handling
Output:
Return code separated by files.
🔹 Generate Tests
You are a QA engineer.
Generate unit tests for this code.
Constraints:
- Use Jest
- Cover edge cases
- Mock dependencies
🔹 Debug Code
You are a senior developer.
Analyze the following code and error.
Explain the issue and provide a fix.