WithUs — The Live Reddit Moderator Suite & Closed-Loop Appeals Queue 🛡️

💡 Inspiration

Moderating growing subreddits is a continuous battle against spam, toxic behaviour, and user frustration. Moderators suffer from severe burnout due to static, slow-refreshing queues, while regular users suffer from a complete lack of transparency—often getting their content removed with no clear path to appeal or understand why.

We built WithUs to create a balanced, transparent community lifecycle. Our goal was to empower moderators with rapid, real-time tools, while closing the loop for users by offering a beautiful, automated content removal appeal queue that sends instant feedback via Reddit DMs.

⚡ What it Does

WithUs is a premium, real-time Moderator Intelligence Suite that splits into five core pillars:

🔥 Real-Time Live Activity Feed: Auto-polls active submissions every $15\,\text{s}$. New posts slide into the viewport with a premium Ivory Gold shadow pulse.
⚡ Inline Comment Moderation: Post rows function as interactive accordions. One click fetches and expands the reported comment tree directly inline, enabling mods to execute instant Approve or Remove actions without ever leaving the dashboard.
🎯 High-Fidelity Appeal Timelines: Appeal cards render a detailed, visual history tree mapping the full timeline: $\text{Submitted} \longrightarrow \text{Reviewed} \longrightarrow \text{DM Dispatched}$.
⚙️ AutoMod AI Copilot: Allows moderators to paste complex AutoModerator YAML configs for instant structural analysis, gap detection, and OpenAI-powered optimization rules.
💎 Public Telemetry Splash: Displays a live public count-up of pending appeals and unmoderated items on load. It is fully decoupled from moderator authentication to protect API rate limits and scale safely.

🛠️ How We Built It & Algorithmic Rigor

We designed WithUs as a modern, high-fidelity Reddit Devvit web view application using a robust serverless-to-memory architecture.

A. Rate Limiting Rolling Window

To prevent duplicate or spam appeals, we implemented a rolling-window rate limiter in Redis. Let $T = {t_i}$ be the set of timestamps of appeals submitted by a user. The submission guard satisfies: $$| { t_i \in T \mid t_{\text{now}} - t_i < 24\,\text{hours} } | \le 3$$

B. Visual Transition Delays (Staggered Animation)

To create fluid, non-blocking viewport rendering, we calculated staggered transition delays dynamically for the incoming feed. For the $i$-th post element in the feed list, the CSS transition delay $D_i$ is defined as: $$D_i = i \times 50\,\text{ms} \quad \text{for } i \in [0, 9]$$

C. Glassmorphism Light Transmittance

Our translucent .r-card layers calculate the composite backdrop blend with an alpha weight of $\alpha = 0.65$: $$C_{\text{final}} = \alpha \cdot C_{\text{elevated}} + (1 - \alpha) \cdot C_{\text{backdrop}}$$

🚧 Challenges We Faced & High-Performance Solutions

Database Concurrency & Time Complexity: Storing list indices in standard Redis string values introduced latency. Standard list index lookup was $\mathcal{O}(N)$ where $N$ is the number of active appeals. We resolved this by building an active migration layer that automatically ports legacy lists into Redis Hashes, shifting field lookups to constant time: $$\text{Data-Access Speedup: } \mathcal{O}(N) \longrightarrow \mathcal{O}(1)$$
API Normalisation: Devvit APIs require full Reddit name prefixes (t1_ for comments, t3_ for posts). We designed a type-safe parser matching: $$\text{fullname}(id) = \begin{cases} id & \text{if } id \text{ begins with } t_k \ \text{prefix} + \text{"_"} + id & \text{otherwise} \end{cases}$$
Rate-Limiting Security: Designing public telemetry that fetches counts without requiring moderator authentication. We built a public stats endpoint (/api/public/stats) that operates safely on Redis memory pools without breaching API security boundaries.

🏆 Accomplishments We're Proud Of

Achieved 100% clean TypeScript compilation and zero ESLint syntactic warnings/errors.
Designed a state-of-the-art visual style ("Google Antigravity Premium") that respects Reddit's native aesthetics while injecting premium glassmorphism and staggering micro-interactions.
Built a fully automated, closed-loop restoration engine: approving an appeal automatically restores and approves the corresponding content on Reddit, notifies the user via DM, and deletes the sanction log.

🧠 What We Learned

We mastered the boundaries of Reddit's Devvit framework, specifically how to build fast, lightweight client-server boundaries under serverless execution time limits, and the importance of using clean, native CSS properties over bloated utility libraries to ensure fast load times.

🚀 What's Next for WithUs

We plan to introduce Multi-Subreddit Federation, allowing mod teams to sync blocklists and sanction histories across sister subreddits, alongside Interactive Visual Ban Analytics to graph mod queue health over 30-day windows.