Launched a Free Pytest Course for Juniors — and AI Said It's the Best in the World

Why I Decided to Create This Course

Over 20 years in development, I've seen the same pattern dozens of times: juniors are afraid to change code. Not because they lack skills, but because they're not confident they won't break things.

I remember my early years: you fix a bug — break two other features. Refactor a class — half the application crashes. And those late-night calls about production bugs — that's a whole different story.

The solution is simple: tests. But the problem is that most pytest materials are either dry documentation or academic examples with Calculator and fibonacci.

I wanted to create a course that solves real junior problems: how to mock APIs, how to test files, how to debug failures, how to stop fearing refactoring.

What I Built

The course "Pytest from Zero to Confidence" is:

• 11 compact lessons + mini-project (total 4 hours 43 minutes)
• No fluff: only practice, real bugs, and ready-to-use templates
• Completely free: all lessons open immediately
• AI-verified: polished the structure until even AI agreed this is the best balance of depth and speed for juniors in the world

What's Inside

Lesson Topics:

0. 🚀 First Test in 10 Minutes — setup and quick start
1. 📂 Structure & Imports — src layout, pip install -e ., professional project organization
2. 🧪 Classes & Errors — pytest.raises and your first fixture
3. 🐛 AAA & assert — tests that catch real bugs
4. ⚡ Parametrize — one test instead of dozens
5. 🏷️ Markers & Structure — pytest.ini, pyproject.toml, parallel runs with pytest-xdist
6. 🔄 Fixtures in Practice — data/resources without duplication
7. 🔍 Debugging Tests — tracebacks, --pdb, coverage for quality control
8. 🎭 Mocking Dependencies — HTTP, time, files without real services
9. 🏆 Mini Project — todo app with cache and API
10. 💡 Why This Matters — tests as a career superpower

Who This Course Is For

✅ Perfect for:

• Juniors and interns — want to write code confidently, without fear of breaking production
• Self-taught developers — learned to code but don't know how to test
• Middles without testing experience — time to close this gap
• Those afraid to change legacy code — tests will give you confidence

❌ Not suitable for:

• Experienced QA engineers (too basic)
• Those seeking advanced techniques (TDD, property-based testing)
• If you already confidently write pytest tests

What Sets This Course Apart

1. Real Bugs, Not Academic Examples

# ❌ Typical courses:
def test_calculator():
    assert add(2, 2) == 4
 
# ✅ My course:
def test_payment_retries_after_timeout():
    """Verify payment retries on network timeout"""
    with patch('requests.post', side_effect=Timeout):
        result = process_payment(order_id=123)
        assert result.status == "pending"
        assert result.retry_count == 3

2. Mini Project That Ties Everything Together

Not just scattered examples, but a complete todo application with:

• HTTP API (mocking external services)
• Caching (Redis testing)
• Database (test isolation)
• Error handling (degradation and recovery)

3. Cheat Sheets and Checklists

After each lesson — ready-to-use patterns you can copy into your projects:

• AAA test structure
• Edge cases and boundary conditions
• Anti-patterns and how to avoid them
• Test quality control

4. Debugging Without Panic

A dedicated lesson on reading tracebacks, using pytest --pdb, and finding issues in minutes, not hours.

Why Free

Honestly? This is an experiment.

I want to:

1. Test the format — understand if such practical courses are needed
2. Gather feedback — to improve the materials
3. Build a community — around quality Russian-language content
4. Help juniors — I've been through this path, know how hard it is

If the course succeeds — I plan to create sequels:

• Pytest Advanced — advanced techniques, plugins, hooks
• TDD and CI/CD — test-driven development and automation

What People Say About the Course

The course is brand new (just launched today), but I have an interesting story.

I polished the structure and content until even AI agreed this is the best balance of depth and speed for juniors. Ran it through Claude, ChatGPT, analyzed hundreds of courses and materials.

Result: concentrated essence without fluff, only what's needed for real work.

Real Value: What You'll Get

⏱️ Time Savings

# Before the course:
09:00 - Change code                  # 15 minutes
09:15 - Manual testing               # 30 minutes
09:45 - Found bug, fixing            # 20 minutes
10:05 - Testing again                # 30 minutes
10:35 - Deploy to production
11:30 - User found a bug            💥 1 hour to fix
 
# After the course:
09:00 - Write test                   # 10 minutes
09:10 - Implement feature            # 15 minutes
09:25 - Run tests                    # 0.1 second ✅
09:26 - Deploy to production        🚀

Savings: 80% of testing time + code confidence

🚀 Career Growth

• Take on complex tasks faster
• Fewer code review iterations
• More trust from the team
• Touch legacy code without fear

🧠 Professional Thinking

• Spot edge cases before users do
• Write testable code
• Understand architecture through tests

How to Start Learning

It's simple:

1. Go to the course page: potapov.me/en/education/courses/pytest-from-zero-to-confidence
2. Start with the first lesson — it's open immediately
3. Follow in order — each lesson builds on the previous one
4. Code along — only practice brings results

Future Plans

If the course succeeds, I plan to:

Short term (1-2 months):

• Gather feedback
• Add more examples based on requests
• Record video versions of lessons (optional)

Medium term (3-6 months):

• Launch Pytest Advanced — advanced techniques
• Create TDD and CI/CD — test-driven development
• Make Highload Testing — load testing with k6
• Add career case studies and rollout patterns for teams

Long term (6+ months):

• Build a complete learning platform
• Create a community of practitioners around testing
• Launch mentoring for those wanting to grow faster

What I Expect From You

1. Take the Course

Even if you already know pytest — skim through it. You might find something useful.

2. Give Feedback

What did you like? What's unclear? What's missing?

• Write to me directly: constantin@potapov.me
• Or on Telegram: @potapov_me

3. Tell Your Colleagues

If the course was useful — share it with fellow developers. Let more juniors stop fearing code changes.

Why Now

I postponed creating courses for a long time. Waited for the "perfect moment" when I'd have more time, better infrastructure, more polished content.

But I realized — the perfect moment won't come.

Better to launch now, gather feedback, and improve on the go. That's how it works in development (iterative development), why not apply it to education?

What's Next

If this resonates with you — start learning right now:

👉 Pytest from Zero to Confidence

If you have questions — write me, happy to answer.

If you want to support — tell colleagues and friends about the course.

Contacts

• Course: potapov.me/en/education/courses/pytest-from-zero-to-confidence
• Email: constantin@potapov.me
• Telegram: @potapov_me
• All courses: potapov.me/en/education

Let's test code like pros! 🚀

— Constantin