DevInterviewMaster
AI tutor for tech interviews, in English or Hinglish
What is DevInterviewMaster?
DevInterviewMaster helps developers get interview-ready with an AI tutor that talks with you in English, Hindi or Hinglish. Work through 8,568 questions, 381 coding problems in an in-browser Monaco editor, 248 HLD and 70 LLD topics, and SQL practice on live schemas. There are also 57 real production incidents (Database, Backend, Frontend, Infra, Distributed), plus DevOps and AI Engineer Zero-to-Hero courses. Start free. Pro is ₹400/month or ₹2,299/year, one-time payment with no auto-renewal. Built by one engineer in India over about a year.
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FounderPlaybooks.
What other founders did to grow.
2722 dispatches from hundreds of founders, pulled from the week's best podcasts.
CTA has to really communicate the free value if it's available so that it's just more comfortable to press that button — if you have a more comforting motion like definitely make sure to have that on the CTA.
CTA must say "try free" — "buy now" kills free-trial conversion
Users are conditioned to fear accidental charges. When a paywall says "buy now" below copy that promises a free trial, the mismatch creates hesitation and killed conversion in Microsoft's tests. The CTA must mirror the offer — "Try free for 1 month" removes the friction that stops people clicking even when they want the product.
You saw a specific feature, you click on it, you get a paywall specific to that content. If you don't unlock it you reiterate everything else you can get with premium, and if they close it then you have an IAP to give them access just to that one feature.
Cascade: feature paywall → premium recap → one-time IAP fallback
A three-layer flow walks users down the demand curve: contextual feature paywall, then a 'here's everything else premium unlocks' second pitch, then a one-off in-app purchase for just the triggering feature. Captures users who reject subscription but will pay once. Google data shows hybrid monetization is a major unlock Android apps already exploit and iOS lags on.
There's a play for whatever you're stuck on.
Read all 2722 playbooks