Developer builds rewindable JavaScript execution visualizer for DSA learning

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Frontend engineer nyaomaru has created DSA View View, an open-source tool that makes JavaScript and TypeScript algorithm execution visual and rewindable. The tool works by using Babel to parse user-written TypeScript into an abstract syntax tree, then injecting recordStep calls to capture intermediate runtime states. Execution runs inside a Web Worker, producing a timeline of snapshots that the React-based UI can play forward or backward like security footage. The project targets developers studying data structures and algorithms who want to observe variable changes, pointer movements, and recursion depth mid-execution, not just the final return value. DSA View View supports 39 built-in examples and handles common DSA types such as TreeNode, ListNode, heaps, matrices, and stacks out of the box.

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