Practice System Design
With a Clear Process

Start with one free interview and 3 focused drills with AI feedback. Buy more interviews as you go, or choose Pro for unlimited interviews and up to 10 new drills per day.

Free allowances do not reset. Interview packs do not add drill access.

One Interview

$4.99

No subscription. Full debrief included.

  • 1 Interview, Chat or Voice, up to 60 Minutes
  • Complete Evidence Report Included
  • Any Question in the Library
  • One-time Payment; Credits Do Not Expire
  • No Additional Focused Drills

Five Interviews

$19.99

No subscription. Full debrief included.

  • 5 Interviews, Chat or Voice, up to 60 Minutes Each
  • Complete Evidence Report Every Time
  • Any Question in the Library
  • One-time Payment; Credits Do Not Expire
  • No Additional Focused Drills
All Access

Pro Membership

$25/month

Unlimited chat and voice. Cancel anytime; premium access ends immediately

Unlimited Chat and Voice Interviews
Up to 10 New Focused Drills per Day
Complete Evidence Report Every Time
Full Solution Articles
Performance History and Trends
Priority Support

Renews automatically every month at $25 USD plus applicable tax until canceled. Cancel online at any time; cancellation stops future charges and premium access ends immediately.

By selecting the subscription button, you authorize these recurring charges, agree to the Terms of Service, and acknowledge the Privacy Policy.

Trying it out?

Try one free interview, in chat or voice, with a full debrief, plus AI feedback on 3 saved drills total. These free allowances do not reset.

Includes:

1 Interview, Chat or Voice, with a Full Debrief
Browse Every Question Prompt
3 Focused Drills with AI Feedback Total
Full Feedback on Your First Interview
Score, Top Insight, and One Drill Afterward

Limits:

Another interview requires a pack or Pro
Focused drill feedback is limited to 3 saved drills total; no reset

A Repeatable Practice Loop

01 · Practice

Explain a complete design

Work through an open-ended prompt while explaining your decisions and building the architecture.

02 · Review

Inspect the reasoning

Review how your response addressed requirements, trade-offs, scale, reliability, and communication.

03 · Repeat

Choose the next drill

Turn the report into concrete follow-up topics, then revisit weak areas in another session.

Voice interviews last up to 60 minutes. Reconnecting uses the same session and does not cost another credit. If our voice provider fails to start a session, we restore the reserved allowance automatically. Paid connection failures reported in the first minute qualify for one automatic credit restoration per day; a replacement voice session is available after the original 60-minute window expires. Contact support if you need help with another failed session.

FAQ

Can I cancel anytime?

Yes. Cancellation downgrades your account to the free tier immediately, so premium access ends as soon as you confirm.

What does the subscription include?

Every question prompt is free to browse and practice. Pro adds unlimited interviews, up to 10 new focused drills per day, a complete evidence report every time, full solutions, and performance history.

Is there a free trial?

Yes. You get one free interview, in chat or voice, with a full debrief, plus 3 focused drills. These allowances do not reset. Interview packs add interviews only; Pro includes continued drill access.

How does drill usage work?

The free allowance covers AI feedback on 3 saved drills total. Retrying feedback on the same drill does not use another slot, and you can return to saved feedback anytime. Pro includes up to 10 new drills per day. Interview credits cannot be used for drills.

Ready for more practice?

Upgrade when you want to repeat the practice-and-review loop without the free-tier session limit.