johnlindquist/claude/lessons

# Write to lessons file
cat >> ~/.claude/lessons.md << 'EOF'
 
## [Date] - [Topic]
 
**Context:** What were you doing?
**Lesson:** What did you learn?
**Application:** When to apply this?
 
EOF

## 2024-01-15 - TypeScript Generic Constraints
 
**Context:**
Building a type-safe form library, struggled with generic types.
 
**Problem:**
Generic function wasn't narrowing types correctly.
 
**Solution:**
Use `extends` constraints to narrow:

 
**Lesson:**
TypeScript generics need explicit constraints for type narrowing.
 
**Tags:** #typescript #generics #types

## Bug: [Brief description]
 
**Symptom:** What happened
**Root Cause:** Why it happened
**Fix:** How to fix
**Prevention:** How to avoid in future
**Time Cost:** How long to debug (motivation to remember!)

## Pattern: [Name]
 
**When to use:** Situations where this applies
**How to implement:** Basic structure
**Gotchas:** Common mistakes
**Example:** Working code

## Tool: [Name]
 
**What it does:** Brief description
**Key commands:** Most useful commands
**Gotchas:** Things that trip people up
**Alternatives:** Other options

# Review recent lessons
tail -100 ~/.claude/lessons.md
 
# Search for topic
grep -A 10 "typescript" ~/.claude/lessons.md

gemini -m pro -o text -e "" "Review these lessons from the past week:
 
$(tail -500 ~/.claude/lessons.md)
 
1. What patterns emerge?
2. What mistakes keep recurring?
3. What should be turned into automation?
4. What needs deeper study?"

# Get relevant lessons
TOPIC="authentication"
grep -B 2 -A 10 -i "$TOPIC" ~/.claude/lessons.md

# Lesson: Always run tests before commit
# → Create pre-commit hook
 
cat > .git/hooks/pre-commit << 'EOF'
#!/bin/bash
npm test || exit 1
EOF
chmod +x .git/hooks/pre-commit

# Lesson: This pattern is useful
# → Save as snippet
 
cat > ~/.claude/snippets/async-error-handling.ts << 'EOF'
async function safeAsync<T>(promise: Promise<T>): Promise<[T, null] | [null, Error]> {
  try {
    const result = await promise;
    return [result, null];
  } catch (error) {
    return [null, error as Error];
  }
}
EOF

# Lesson: Keep forgetting these steps
# → Create checklist
 
cat > ~/.claude/checklists/pr-review.md << 'EOF'
# PR Review Checklist
- [ ] Tests pass
- [ ] No console.logs
- [ ] Types are explicit
- [ ] Error handling present
- [ ] Documentation updated
EOF

gemini -m pro -o text -e "" "Extract lessons learned from this coding session:
 
[Paste conversation or summary]
 
For each lesson:
1. What was learned
2. When it applies
3. How to remember it"

gemini -m pro -o text -e "" "Find connections between these lessons:
 
$(cat ~/.claude/lessons.md)
 
1. What themes emerge?
2. What knowledge gaps exist?
3. What should be studied next?"

gemini -m pro -o text -e "" "Create a quiz from these lessons:
 
$(tail -1000 ~/.claude/lessons.md)
 
Generate 5 questions that test understanding of key concepts."

# Single file
~/.claude/lessons.md
 
# By date
~/.claude/lessons/2024-01.md
 
# By topic
~/.claude/lessons/typescript.md
~/.claude/lessons/git.md

# Save to basic-memory
basic-memory tool write-note \
  --title "Lesson: TypeScript Generics" \
  --folder "lessons" \
  --content "$(cat lesson.md)" \
  --tags "lesson,typescript"