Md Nasim Sheikh
Founder and lead engineer, Preptics · @nasimstg
Founder of Preptics. A full-stack engineer who built its adaptive exam engine and wrote the scoring method behind every score range it reports.
BackgroundLink to the section: Background
Nasim founded Preptics and built it: the adaptive exam engine that chooses each section's second module from how the first one went, the module clocks held on the server, the scoring method that reports a range with its confidence stated, and the checks every question passes before a student sees it.
Nasim has built for the web professionally since 2022 — first as a backend developer, then as a freelance full-stack engineer shipping more than fifty minimum viable products for clients, and since 2025 leading engineering on a quiz and learning-management platform. The working stack is TypeScript, Next.js, Node.js and PostgreSQL, deployed on Vercel, Google Cloud and Cloudflare.
Outside Preptics, Nasim maintains open-source developer tools, among them xenvsync, which encrypts environment secrets so a team can commit and share them safely, and SkillTreeOSS, which maps skills into step-by-step roadmaps for self-taught learners.
What Nasim does at PrepticsLink to the section: What Nasim does at Preptics
- Designed and built the multistage adaptive exam engine, including module routing and server-held timing
- Wrote the published scoring method: section and total ranges, each with a stated confidence
- Built the question pipeline — blind solves by three AI models, arithmetic executed as code, then review by a person
- Built the study planner that works backwards from a published College Board test date
- Runs the platform itself: the database, hosting, email, and the security reviews behind them
The methods behind this work are public: how scores work and how questions are made.
Writes aboutLink to the section: Writes about
How Digital SAT scoring and adaptive testing work — module routing, raw-to-scaled conversion, and what a practice score range can and cannot tell you.
- Digital SAT scoring
- Multistage adaptive testing
- Item response theory
- Full-stack web development
- Web publishing
- Next.js
- PostgreSQL
- Vercel
- Google Cloud
Guides by NasimLink to the section: Guides by Nasim
What does a practice SAT score range actually mean?
Why a practice test should report a range like 1210–1290 rather than a single number, what the width of that range is telling you, and how to use it against a target school.
How does adaptive module routing work on the Digital SAT?
The Digital SAT routes you to an easier or harder second module based on your first. What that means for your score, why the two paths are not equivalent, and what it changes about how you practise.
How is a raw SAT score converted into a scaled score?
What a raw score is, why the conversion to 200–800 is a lookup table rather than a formula, why the curve is not a straight line, and why no third party has the real one.
Why did my friend and I get different scores with the same number correct?
Two people can answer the same number of Digital SAT questions correctly and receive different section scores. Why that happens, why it is not a bug, and what it tells you about your own result.
How accurate are practice SAT scores?
What a practice score can and cannot predict, the three sources of error between a mock and test day, and how to make your own practice scores more informative.
Every guide is held to the same editorial standards. Spotted a mistake? Email support@preptics.com and it will be corrected, with the date changed to say so.