Mimir

Overview

Mimir is an Android app built for reading CS interview-prep notes, not quizzing on them. Instead of scattering theory across YouTube playlists, PDFs, and random websites, it pulls everything into one clean, offline-first reader.

Content and app are fully decoupled: notes live as plain Markdown files in a separate GitHub repository, and the app fetches and caches them at runtime. New topics can be added at any time with nothing more than a git push, with no rebuild and no reinstall.

Features

• Clean, distraction-free Markdown reader for CS topics
• Subject → category → topic navigation, three taps to any note
• Full-text search across every topic in the index
• Offline-first, reads from local cache after the first sync
• Pull-to-refresh to manually re-sync new content
• Adjustable text size and mark-as-read tracking per topic
• Dark-first Material 3 theme

Requirements

• Android 7.0 or higher
• Internet connection for the initial content sync
• A GitHub repository hosting the Markdown notes and index files
• Android Studio (only if building from source)

Usage

• Open the app, it syncs the topic index on first launch
• Browse by subject, then category, then topic
• Or tap search and jump straight to any topic by name
• Pull down on the home screen anytime to check for new content

Content Format

The app expects two files at the root of the content repository:

• index.json, the navigation tree (subjects → categories → topics), with each topic pointing to a relative Markdown file path
• meta.json, containing { "version": N }, bumped on every content update, which the app checks to decide whether to re-sync

Setting a custom content source is a single line in Config.kt:

const val CONTENT_BASE_URL = "https://raw.githubusercontent.com/<user>/<repo>/main/"

Tech Stack

• Kotlin + Jetpack Compose
• Material 3 (dark-first theme)
• Navigation Compose
• OkHttp for fetching content
• kotlinx.serialization for JSON
• Markwon for Markdown rendering
• DataStore for lightweight local state (read/unread tracking)

Known Limitations

Mimir favors simplicity over feature bloat. It is intentionally just a reader, not a quiz engine or a note-taking tool.

• No in-app content editing, notes are written and pushed via GitHub
• Sync is not real-time; it checks on launch and on pull-to-refresh
• Relies on GitHub's raw content CDN, which can briefly serve a stale response for a few minutes right after a push
• No account system, so read/unread progress does not sync across devices

Future Enhancements

• Spaced-repetition based revision scheduling
• Per-subject progress tracking
• Custom app icon and branding
• Public release with a starter content pack

Development Notes

Mimir started as a way to stop losing track of interview prep across a dozen scattered PDFs and playlists. The core design decision was keeping content completely separate from the app itself. GitHub acts as a free, versioned CMS, and the app is just a thin reader on top of it.

That split means adding a new topic is as fast as writing a Markdown file, and the app itself rarely needs to change once the reading experience is right.