PseudoMastery - Web based interpreter for pseudocode
Abdul Rafay
Founded and shipped a SaaS developer playground for O/A Level CS students - a browser-based pseudo-language IDE with a step-by-step execution visualizer and automated grading engine, hosted on Azure with a real user base.
The Problem
O/A Level CS students preparing for Cambridge examinations must master a strict pseudo-language syntax with no digital tool to validate their logic, catch errors in real time, or show how their code executes step by step. Every practice session was pen-on-paper with zero feedback until the exam itself.
The Build
Founded and built the entire platform as a solo venture using Next.js, TypeScript, and a cloud-hosted Azure database.
Browser-Side Parser: Built a custom client-side parser that validates pseudo-language syntax in real time, providing instant compiler-style feedback without server-side execution
Execution Visualizer: Built a runtime state tracker that captures variable mutations, loop iterations, and program flow frame-by-frame, all rendered as an interactive visual tree students can step through
Automated Grading Sandbox: Integrated an I/O test case evaluation engine that grades student logic against expected outputs in real time, scoped specifically to Cambridge pseudo-language patterns
The Outcome
Launched, acquired real users, and operated a live SaaS product on Azure cloud infrastructure. Closed a gap that no existing tool addressed - giving students a Cambridge-specific practice environment built entirely from scratch by a solo founder.
Few of the features offered in the product
Feedback from users on how the product solves their needs
IDE - the main playground to write pseudocode and see it's results in terminal
Visualizer - a step-by-step guide on how each line of pseudocode runs
List of available questions for users to try out their skills
Code Arena in action - write code based on description and pass the automated test cases
Syntax Guide for new learners
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Posted May 27, 2026
Founded and shipped a SaaS developer playground for O/A Level CS students - a browser-based pseudocode IDE with a step-by-step execution visualizer.
