mock-interview
Run an interactive system design mock interview - simulates a real interview with problem statement, follow-ups, and structured feedback
What this skill does
# Mock Interview Command
This command runs a full interactive system design mock interview, simulating a real interview experience with problem presentation, follow-up questions, and structured feedback.
## Purpose
Provide realistic interview practice including:
1. Problem selection based on type and level
2. Timed interview simulation
3. Realistic follow-up questions and pushback
4. Structured feedback on performance
5. Specific improvement recommendations
## Interview Types
| Type | Focus | Interviewer Agent |
|------|-------|-------------------|
| `general` | Classic system design (URL shortener, Twitter, etc.) | architecture-critic |
| `ml` | ML systems (recommendation, search, fraud detection) | ml-interviewer |
| `data` | Data systems (pipelines, warehouses, streaming) | data-architect |
| `staff` | Staff+ level with hard pushback | senior-staff-interviewer |
## Workflow
### Phase 1: Interview Setup
**Parse arguments:**
- Determine interview type (default: general)
- Extract any problem hints or preferences
- Set difficulty level based on type
**Ask about preferences if needed:**
```text
Interview Setup:
1. Interview Type:
- General system design (classic problems)
- ML system design (recommendation, search, etc.)
- Data engineering (pipelines, warehouses)
- Staff+ level (rigorous, pushback-heavy)
2. Time Constraint:
- 30 minutes (focused)
- 45 minutes (standard)
- 60 minutes (comprehensive)
3. Problem Preference:
- Surprise me (recommended)
- Specific domain: [e-commerce, social, fintech, etc.]
```
### Phase 2: Problem Presentation
**Select and present problem based on type:**
For `general`:
```text
Problem Examples:
- Design a URL shortening service like bit.ly
- Design a rate limiter for an API
- Design a distributed cache system
- Design a notification service
- Design a file sharing service like Dropbox
```
For `ml`:
```text
Problem Examples:
- Design a content recommendation system
- Design a search ranking system
- Design a fraud detection system
- Design a RAG-based chatbot
- Design an LLM serving infrastructure
```
For `data`:
```text
Problem Examples:
- Design a real-time analytics pipeline
- Design a data warehouse for an e-commerce company
- Design an event sourcing system
- Design a change data capture system
- Design a feature store
```
For `staff`:
```text
Problem Examples:
- Design a payment processing system ($100B scale)
- Design a global social media feed
- Design a multi-region database system
- Design a real-time bidding system
- Design a distributed transaction coordinator
```
**Present the problem:**
```text
═══════════════════════════════════════════════════════════════
SYSTEM DESIGN INTERVIEW
═══════════════════════════════════════════════════════════════
Problem: [Problem Statement]
[1-2 paragraphs with requirements and context]
Constraints:
- [Key constraint 1]
- [Key constraint 2]
- [Scale indicator if applicable]
You have [X] minutes. You may ask clarifying questions.
When ready, begin by gathering requirements.
═══════════════════════════════════════════════════════════════
```
### Phase 3: Spawn Interviewer Agent
Based on interview type, spawn the appropriate agent:
- `general` → spawn `architecture-critic` agent in interviewer mode
- `ml` → spawn `ml-interviewer` agent
- `data` → spawn `data-architect` agent in interviewer mode
- `staff` → spawn `senior-staff-interviewer` agent
**Agent instructions:**
```text
Conduct a system design interview for the following problem:
[Problem statement]
Interview parameters:
- Duration: [X] minutes
- Level: [Type/Level]
- Mode: Interactive interview
Interview phases:
1. Requirements (5 min) - Let candidate ask clarifying questions
2. High-level design (10 min) - Evaluate system components
3. Deep dive (15 min) - Probe 2-3 components in depth
4. Trade-offs (5 min) - Discuss alternatives and evolution
During the interview:
- Push back on surface-level answers
- Ask follow-up questions
- Simulate realistic time pressure
- Note strengths and areas for improvement
At the end, provide structured feedback.
```
### Phase 4: Interview Execution
The interviewer agent conducts the interview:
**Throughout the interview:**
- Present clarifying questions when candidate drives
- Provide incomplete information initially
- Probe deeper on interesting areas
- Challenge assumptions
- Track time and give updates
- Note key decisions and reasoning
**Example interactions:**
```text
Interviewer: "What questions do you have about the requirements?"
[After clarifying questions]
Interviewer: "Good questions. Let's start with your high-level design.
How would you approach this system?"
[After high-level design]
Interviewer: "Interesting choice with [component]. Let's dive deeper.
How would you handle [specific scenario]?"
[Probing]
Interviewer: "What happens when [failure scenario]?"
Interviewer: "How does this scale to 10x the load?"
Interviewer: "Why did you choose X over Y?"
```
### Phase 5: Feedback Delivery
After the interview, provide structured feedback:
```text
═══════════════════════════════════════════════════════════════
INTERVIEW FEEDBACK
═══════════════════════════════════════════════════════════════
## Overall Assessment
Rating: [Strong Hire / Hire / Lean Hire / No Hire]
Level: [Appropriate for: Junior / Mid / Senior / Staff]
## Strengths
1. [Strength 1 with specific example]
2. [Strength 2 with specific example]
3. [Strength 3 with specific example]
## Areas for Improvement
1. [Area 1 with specific recommendation]
2. [Area 2 with specific recommendation]
3. [Area 3 with specific recommendation]
## Component Coverage
| Component | Coverage | Depth |
|-----------|----------|-------|
| [Component 1] | [Good/Partial/Missing] | [Shallow/Adequate/Deep] |
| [Component 2] | [Good/Partial/Missing] | [Shallow/Adequate/Deep] |
## Key Moments
✓ Good: [Positive moment]
✓ Good: [Positive moment]
✗ Miss: [Missed opportunity]
✗ Miss: [Missed opportunity]
## Recommendations for Practice
1. [Specific topic to study]
2. [Skill to develop]
3. [Pattern to practice]
## Resources
- [Relevant skill to load]
- [Related practice problem]
═══════════════════════════════════════════════════════════════
```
## Usage Examples
```bash
# General system design interview
/sd:mock-interview general
# ML-focused interview
/sd:mock-interview ml
# Data engineering interview
/sd:mock-interview data
# Staff+ level rigorous interview
/sd:mock-interview staff
# Specific domain preference
/sd:mock-interview general e-commerce
# ML interview with specific focus
/sd:mock-interview ml "recommendation system"
```
## Interview Best Practices (For Candidates)
The command will share these at the start:
```text
Interview Tips:
1. START with clarifying questions
- Don't jump to solutions
- Understand requirements and constraints
2. STRUCTURE your approach
- Start high-level, then dive deep
- Use diagrams (describe them clearly)
3. THINK aloud
- Share your reasoning
- Discuss trade-offs as you go
4. MANAGE time
- Don't spend too long on one area
- Cover breadth before depth
5. ACKNOWLEDGE uncertainty
- It's okay to say "I'd need to research X"
- Better than guessing incorrectly
```
## Output
The command produces:
1. **Interactive Interview** - Realistic interview simulation
2. **Structured Feedback** - Detailed performance assessment
3. **Practice Recommendations** - Specific next steps
## Related Skills
This command leverages:
- `design-interview-methodology` - Interview framework
- `estimation-techniques` - Capacity calculations
- `quality-attributes-taxonomy` - NFR coverage
## Related Agents
Spawned based on interview type:
- `architecture-critic` - General system design
- `ml-interviewer` - ML systems
- `data-architect` - Data engineering
- `senior-staff-interviewer` - Staff+ level
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