Devin

#The Problem

AI pair programming tools (Cursor, Copilot) require your attention. You can’t start a complex task and walk away—you need to be there for the back-and-forth.

#The Solution

Devin’s session-based workflow is designed for async development:

1. Start a session with a clear task
2. Walk away (meeting, lunch, sleep)
3. Return to completed work
4. Review and iterate

#How to Structure Effective Sessions

#Be Specific About Success

Bad prompt:

Improve the API performance

Good prompt:

Optimize the /users endpoint:
- Current: 800ms average response time
- Target: under 200ms
- Constraints: Don't change the API contract
- Test with: npm run benchmark:users

#Include Context Devin Can’t See

Task: Fix the checkout flow bug

Context:
- Bug report: Orders sometimes double-charge
- Happens ~2% of the time
- Likely race condition in payment processing
- Relevant files: src/checkout/*, src/payment/*
- We use Stripe for payments
- Test account: [stripe test keys]

#Define Done

Success criteria:
1. No double charges in 1000 test transactions
2. All existing tests pass
3. Add regression test for this bug
4. Document the fix in PR description

#Async Workflow Example

#Morning (9:00 AM)

"Devin, implement the user notification preferences feature:
- Add preferences table (email, push, SMS toggles)
- Create CRUD endpoints
- Add settings UI page
- Write tests for all endpoints
- Follow patterns in existing features (see /src/features/profile)

I'll review at lunch. Ping me in Slack if blocked."

#Lunch (12:00 PM)

Check Devin’s progress:

• Review PRs it opened
• Check for questions in Slack
• Provide clarification if needed

#Afternoon (2:00 PM)

"Good progress on notifications. Changes:
- Use React Query instead of plain fetch
- Match the toggle style in ProfileSettings
- Add preference for daily digest emails

Continue and ping when done."

#End of Day (5:00 PM)

• Review final implementation
• Merge or request changes
• Queue next task for tomorrow

#Pro Tips

#Parallel Sessions

Run multiple Devin sessions on independent tasks:

• Session 1: Backend API feature
• Session 2: Documentation update
• Session 3: Test coverage improvement

#Task Templates

Create standard prompts for common work:

Bug Fix Template:

Bug: [description]
Repro steps: [how to trigger]
Expected: [correct behavior]
Actual: [current behavior]
Files: [likely locations]
Tests: [how to verify fix]

Feature Template:

Feature: [name]
User story: [who wants what why]
Acceptance criteria: [list]
Similar features: [reference implementations]
Constraints: [limitations]

#Check-in Intervals

Set expectations for progress updates:

"Update me every 30 minutes or when you hit a decision point."

Devin will proactively share progress.

#When Sessions Work Best

✓ Well-defined tasks with clear success criteria ✓ Independent work (no constant collaboration needed) ✓ Boilerplate-heavy implementation ✓ Migrations and refactoring with clear patterns ✓ Test writing for existing code ✓ Documentation generation

#When to Pair Instead

✗ Exploratory work (unclear requirements) ✗ Design decisions requiring human judgment ✗ Customer-facing UX (needs human eye) ✗ Security-critical code (needs expert review during, not after)

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Devin isn’t your pair programmer—it’s your async team member. Structure work accordingly.