decod

decod hidden words encoded from the 21x21 gri

Inspiration

We drew inspiration from Reddit’s own r/place and r/pixelary, where thousands of users collaboratively placed pixels on a shared canvas. We wanted to capture that same spirit of creativity and real-time collaboration but also add a puzzle element—giving redditors a goal to work toward together.

What it does

decod is a community-driven pixel-placement puzzle game. Users can place a single black or white pixel every 3 seconds on a shared canvas. The collective goal is to decode hidden valid english words (similar to forming a QR code or discovering secret patterns). Once a valid configuration emerges, the puzzle is considered “solved,” and users who helped finalize it earn points on the leaderboard.

How we built it

Devvit (Reddit’s Developer Platform): We used Devvit’s block-based UI to create interactive posts that run on both desktop browser and mobile Reddit.
Redis Storage: Each pixel placement, user action, and puzzle state is stored in Redis, allowing for quick reads/writes and near real-time updates.
TypeScript: Our code is written in TypeScript, which runs in Devvit’s serverless Edge environment. -Asynchronous Multiplayer: We leveraged Devvit’s built-in channel and realtime system to broadcast pixel changes to everyone actively viewing the puzzle post.

Challenges we ran into

-Real-time Updates: Ensuring that every user saw canvas changes in a timely manner, while keeping Devvit’s block-based UI efficient.

Cooldown Mechanics: We had to implement per-user timers to ensure that players only place pixels at intervals, preventing spam or botting. And we had to use useInterval from devvit api.
Data Synchronization: Managing concurrency and consistency in Redis, so pixel placements never get “out of sync.”
And lastly, the Ask AI from the devvit docs was quite helpful, even though the answer was not always correct. For example gneerating code including useEffect, which is not in the API of devvit.

Accomplishments that we're proud of

Fully Collaborative Experience: The community can collectively shape the canvas and discover hidden words (or codes).
Leaderboard Integration: We track each user’s contributions—pixels placed, words discovered, challenges joined—and display these stats in a neat leaderboard. And teh hapiness of seing the user score is :)
Extensibility: The game can be easily adapted to new puzzle mechanics (e.g., color expansions, different grid sizes, or coded messages). -Performance & Scalability: By carefully leveraging Redis and Devvit’s block-based UI, the app scales to many users simultaneously.

What we learned

Devvit Ecosystem: We got hands-on with Devvit’s block-based UI, triggers, and scheduling features. -Async Gameplay on Reddit: Building asynchronous, bite-sized gameplay fosters a unique social dynamic-players can dip in and out without missing out on progress.
Community Interaction: Reddit’s culture encourages quick feedback, co-creation, and emergent gameplay mechanics.

What's next for decod

New Puzzle Modes: Add more complex shapes, multi-step puzzles, or color expansions.
Scheduled Events: Weekly or monthly puzzle resets to keep the community engaged.
User-Created Puzzles: Let moderators or community members to chose the number of grid they want instead of jhaving static 21x21 grid.
Reward System: Possibly integrate flairs, badges, or tokens for top contributors and puzzle-solvers.