HN Save Edit
About this project
It is a web app that lets you edit save files for Hollow Knight and Hollow Knight: Silksong by Team Cherry. It allows uploading a save file and editing its content visually or in an advanced mode. It supports different save formats for PC and Nintendo Switch. Note: this is not meant to encourage cheating; the project was created for fun, love, and a desire to learn.
Key Features
- Fully in the browser: No data is sent to servers; the entire app runs on the client.
- PWA support: Install it locally as a PWA and get direct desktop access.
- Offline use: Once installed, it can be used without an internet connection.
- Two modes of use: Guided form-based mode and an advanced mode to edit all save data.
Challenges
This project came from the challenge of understanding and working with save files without clear official documentation. That required analyzing their structure, interpreting data, and enabling edits without compromising the player’s progress. The goal was also to build a tool that runs fully in the browser, sending nothing to servers, prioritizing privacy and performance, while remaining accessible to different user types through a simple visual interface and an advanced mode. It also meant supporting multiple formats and platforms, working offline as a PWA, and balancing ease of use with technical control—turning it into a practical learning space for file processing, frontend development, and building useful tools for the community.
Learnings
The work deepened my understanding of analyzing and parsing binary and structured files, manipulating local data safely in the browser, and designing interfaces that translate technical information into clear user actions. It also provided experience building PWAs with offline support, client-side state and persistence, and decision-making focused on privacy and performance. Practically, it strengthened my ability to balance simplicity with advanced control in a single tool, validate assumptions without official documentation, and turn an experimental project into a usable solution for real users, while leveraging Tailwind CSS to accelerate UI development and maintain visual consistency through utilities and reusable components.