Backend Engineering Course: VeyraOps AI
A Complete Backend Engineering Education Based on a Real Production System
Welcome to a comprehensive backend engineering course built entirely around VeyraOps AI's actual codebase — not a toy example, not a generic tutorial. Every claim in this course is checked against backend/app/ directly, including the bugs.
🎯 Course Mission
This course exists to teach you every implementation in the VeyraOps AI backend until you can:
- Rebuild the entire backend from scratch without looking at the code
- Explain every engineering decision — and identify the ones that were never fully finished
- Extend the system with new features confidently
- Debug any issue by understanding the complete data flow
- Interview as a Backend Engineer, using this project — bugs and all — as your portfolio
🧠 What Makes This Course Different
Traditional Documentation
- Lists API endpoints
- Shows idealized examples
- Assumes the code is correct
This Course
- Reads the actual source, function by function, endpoint by endpoint
- Documents real bugs found while writing it (the broken
/statsendpoint, the empty-context crash ingenerate_rag_answer, the chat endpoint's missing conversation memory) instead of glossing over them - Corrects its own earlier mistakes in the open (an earlier draft claimed the email workflow uses LangGraph — it doesn't; that's fixed and flagged in Lesson 12)
- Is honest about what's not implemented (no auth, no tests, no caching, no background tasks) instead of inventing content for topics the code doesn't have
📚 Course Structure
36 lessons across 7 modules, plus a reference section.
| Module | Lessons | Focus |
|---|---|---|
| 1. Foundation | 00, 01–05 | Architecture, request lifecycle, folder structure, database setup |
| 2. Data Layer | 06–08 | Models, schemas, service-layer overview |
| 3. Services Deep Dive | 08a–08e | Line-by-line: OpenAI, monitoring, multi-agent email, documents, RAG graph |
| 4. API & Business Logic | 09, 09a–09b, 10–13 | Every endpoint in both routers, dependency injection, auth, workflows, agents |
| 5. Advanced AI Engineering | 14–20 | RAG pipeline, embeddings, ChromaDB, LangGraph, background tasks, prompts, memory |
| 6. Production Mastery | 21–27 | Logging, exception handling, testing, performance, security, caching, config |
| 7. Integration & Flow | 28 | End-to-end request walkthrough |
📖 Complete Lesson Index
🏗️ Module 1: Foundation
| Lesson | Title |
|---|---|
| 00 | Course Introduction |
| 01 | Project Overview |
| 02 | Backend Architecture |
| 03 | Request Lifecycle |
| 04 | Folder Structure |
| 05 | Database Layer |
💾 Module 2: Data Layer
🔧 Module 3: Services Deep Dive
| Lesson | Title |
|---|---|
| 08a | OpenAI Service |
| 08b | Monitoring Service |
| 08c | Multi-Agent Email |
| 08d | Document Service |
| 08e | RAG Graph Service (LangGraph) |
🔌 Module 4: API & Business Logic
| Lesson | Title |
|---|---|
| 09 | API Routers Overview |
| 09a | Agents Router Deep Dive |
| 09b | Documents Router Deep Dive |
| 10 | Dependency Injection |
| 11 | Authentication |
| 12 | Multi-Agent Workflows |
| 13 | AI Agents |
🤖 Module 5: Advanced AI Engineering
| Lesson | Title |
|---|---|
| 14 | RAG Pipeline |
| 15 | Embeddings |
| 16 | Vector Databases & ChromaDB |
| 17 | LangGraph & Corrective RAG |
| 18 | Background Tasks |
| 19 | Prompt Engineering & Tool Calling |
| 20 | Memory & Context Management |
🚀 Module 6: Production Mastery
| Lesson | Title |
|---|---|
| 21 | Logging & Observability |
| 22 | Exception Handling |
| 23 | Testing |
| 24 | Performance |
| 25 | Security |
| 26 | Caching |
| 27 | Configuration & Environment Variables |
🔄 Module 7: Integration & Flow
| Lesson | Title |
|---|---|
| 28 | Complete Backend Flow |
📚 Reference
| Document | Purpose |
|---|---|
| Exercises | 20 exercises, all grounded in this codebase's real functions, endpoints, and bugs |
| Interview Questions | Verifiable Q&A tied to actual source |
| Glossary | Every technical term explained |
🎓 How to Use This Course
For Complete Beginners
- Start with Module 1 — Foundation is crucial
- Read every lesson in order — each builds on the previous
- Work the exercises as you go — every one is grounded in real code, not invented scenarios
- Type the code out yourself rather than copy-pasting
For Intermediate Developers
- Skim Module 1
- Focus on Modules 3–6 — services, APIs, advanced AI engineering, and production readiness
- Study Module 7 for the end-to-end picture
- Fix the real bugs documented throughout as exercises
For Senior Engineers
- Review Module 2 for data-modeling trade-offs (why
estimated_costis aString, whydue_dateisn't a real date type) - Study Modules 5–6 for the honest gap analysis (no tests, no caching, no auth, no background tasks) and use it as a code-review exercise
- Use the Interview Questions to prep others, or yourself
🔧 Prerequisites
Required Knowledge
- Python basics (variables, functions, classes)
- Basic understanding of web concepts (HTTP, APIs)
- Command line basics
Recommended Knowledge
- SQL fundamentals
- REST API concepts
- JSON format
Tools You'll Need
- Python 3.14+ and
uv - A code editor
curlor Postman for API testing
📜 Philosophy
1. Real Projects Teach Better Than Toy Examples — you're learning from a production system with real trade-offs and real unfinished corners, not a contrived tutorial.
2. Every Line Matters — including the ones that are wrong. A GET endpoint that deletes data, a chat endpoint with no memory, and a factually incorrect claim in an earlier draft of this course are all left visible and explained, not quietly fixed and hidden.
3. Coverage Means Verified, Not Claimed — every lesson in this course is checked directly against backend/app/ source. Where the codebase doesn't implement something (auth, tests, caching, background tasks), the corresponding lesson says so plainly instead of describing a feature that doesn't exist.
4. Depth Over Breadth — one system understood completely, mistakes included, is worth more than ten systems understood superficially.
🚀 Let's Begin
Start with Lesson 00: Course Introduction or jump straight to Lesson 01: Project Overview.
Last Updated: 2026-07-18 Course Version: 2.0 — verified against source, gaps closed, false claims corrected