Cultural Quiz

About the Project

Culture Guide is an automated, interactive onboarding platform for Reddit communities. Built natively on Devvit Web, it replaces passive text-based rules and frustrating bot removals with an identity-secure, gamified verification experience that ensures users understand a community's unique norms before their content goes live.

Inspiration

Every moderator dreads the day their niche subreddit hits the front page. Viral growth brings an influx of passionate new users, but it also triggers the "Eternal September" phenomenon—where the community's unique culture and strict rules are instantly diluted by people who don't read the sidebar.

Traditional tools fail this crisis:

AutoModerator removes posts with generic, cold text responses that leave new users feeling alienated or shadowbanned.
Banning users kills long-term community growth.
The "Mobile Mod Deficit" means moderators can't keep up with massive queues from their phones.

We wanted to create a tool that moves moderation from punitive to educational. We asked: What if instead of banning a user for breaking a rule, we locked them in a fun, 60-second "escape room" where they learn the rules to unlock their post?

What it does

Culture Guide acts as a smart, automated gatekeeper for subreddits:

The Intercept: When an unverified user submits a post, our backend PostCreate trigger instantly removes it from the public feed to protect the community.
The Invitation: The app securely sends the user a Modmail notification containing a direct link to a personalized, hidden "Ghost Post."
The Interactive Quiz: When the user clicks the link, they open a beautiful, native React UI. The quiz pulls dynamic questions based directly on the actual rules of the subreddit.
The Reward: If the user passes with a 100% score, the server instantly executes a multi-step operation: it approves their original post (bringing it back to life), grants them a "Cultural Contributor" user flair, and permanently self-destructs the quiz post to prevent cheating.

How we built it

We leaned heavily into the modern Devvit Web full-stack architecture:

Frontend: Built with React and TypeScript for dynamic UI states and haptic-style error shaking, styled beautifully with Tailwind CSS for a native, mobile-first look.
Backend: Powered by a high-performance Hono server routing internal endpoints.
State & Security: We engineered an Identity-Aware Core using Redis to lock quiz instances to specific userId strings, preventing link-sharing. Redis TTLs handle the 12-hour expiration window.
Automation: Leveraged Devvit's Scheduler to manage the cleanup of expired or abandoned quizzes, ensuring the subreddit backend remains clean.

Challenges we ran into

Building a real-time content intercept system came with major architectural hurdles:

The Infinite Loop of Doom: Our first prototype caused an infinite loop because creating a new Quiz post re-triggered the PostCreate event. We solved this by implementing a strict Guard Clause that checks the appUser.id and gracefully exits if the app itself authored the post.
The Privacy Wall: We initially hit severe NOT_WHITELISTED_BY_USER_MESSAGE gRPC errors when trying to send direct PMs to users with tight privacy settings. We resolved this by building a dual-path fallback system that routes notifications through Modmail when standard PMs fail.
Ghost Post Visibility: We had to deeply study how Reddit handles deleted vs. removed states. We discovered that a standard removed custom post remains perfectly interactive for its author via a direct link, allowing us to build "invisible workspaces" that don't clutter the main subreddit feed.

Accomplishments that we're proud of

Server-Side Security: We successfully separated the validation logic. Users cannot "inspect element" or hack the JavaScript to bypass the quiz because the answer verification and reddit.approve() actions live entirely behind server-side Hono endpoints.
Flawless UX Loop: Creating a true "friction-then-reward" loop where a hidden post instantly reappears in the feed with zero moderator clicks required.
Mobile-Ready Moderation: Solving the mobile deficit by using a Subreddit Context Menu item, allowing mods to see user quiz performance right from the official mobile app.

What we learned

We learned that security on decentralized web platforms requires "Defense in Depth." Simply hiding a link isn't enough; identity verification must happen at every level of the state machine. We also discovered that users are incredibly receptive to learning community rules when the interface is game-like and provides an instant reward (getting their post approved).

What's next for Cultural Quiz

LLM-Driven Dynamic Questions: Integrating an AI layer that reads the user's specific removed post and generates 3 tailored quiz questions explaining exactly which rules they almost broke.
Advanced Analytics Dashboard: Giving moderators detailed charts showing which rules are most confusing to newcomers so they can rewrite their sidebar for better clarity.
Surge Mode Tiering: Automatically turning the gatekeeper on only when a post hits r/all or when the subreddit experiences a 500% spike in traffic.