Hi Everyone!
I've been building ModLookout, a moderation app for Reddit that was based off my moderation bot from the r/PokeLeaks subreddit which has over 150,000 members and tens of thousands of visitors during busy peak season. It was also created to fill in for me and my team when we were not around based on the issues that we faced during our time modding and fill in the gaps for desired functions that AutoModerator could not perform. I also found it very annoying to onboard a bunch of different bots, especially for detecting reposts.
I've rebuilt it. It's now in public testing for any moderators and subreddits to install. It may not be needed and be redundant for some subreddits but it worked for mine and I would hope it would help others as well. I would greatly appreciate any feedback and consider any requests for future functions.
What it does
**Removes reposted images.** New image posts are checked against earlier posts, including galleries, GIFs and WebP. Reposts are removed with a short comment linking to the original. Mirrored, bordered and cropped copies are caught too, and uncertain matches are reported instead of removed.
**Learns from your moderators.** Approving a removed post teaches it not to flag that pair again.
**Catches copy-paste spam.** Users posting the same text over and over are reported or removed.
**Submission Stream.** Optionally filter new posts into the mod queue. Original images are approved automatically and reposts are removed.
**Report handling.** Remove or approve posts and comments after a set number of reports per rule. Reddit's site-wide report reasons always stay for a moderator.
**Posting limits and strikes.** Limit posts per user, track removals, and get a modmail alert or ban at a number you choose.
**Comment review.** Restores comments AutoModerator removed by mistake, based on your team's past decisions.
**Moderator tools.** Image History, Ban This Image, User Info and Nuke Comment Thread on posts and comments.
**Event mode.** Limit which post flairs users can pick during busy periods.
How it's built
* Devvit Web (0.14.8) with a Hono server. Everything runs inside Devvit: no outside servers, and the only HTTP domain it uses is i.redd.it.
* Images (JPEG, PNG, GIF and WebP) are decoded in the app and turned into perceptual hashes. Mirrored, border-trimmed and center-cropped versions are checked too.
* Optional keypoint matching (ORB, with RANSAC geometric checks) catches heavy edits like one-sided crops, captions and screenshots. A visual-word index in Redis keeps the search fast across the whole database.
* Matching thresholds tune themselves from moderator approvals and removals.
* Old posts are indexed in the background in short scheduler jobs, so triggers never time out.
Setup
Install it, and repost removal and spam reporting start right away. Everything else is off until you turn it on. All settings are in one **ModLookout** item in your subreddit's mod menu, with a 30-day overview. No code or AutoModerator changes are needed.
Privacy
Everything is stored in Reddit's own app storage for your subreddit. Nothing is sent outside Reddit, and images are never saved, only small fingerprints of them.
Install: https://developers.reddit.com/apps/modlookout
Comment here or message me through the app page. I'd especially like to hear from other Devvit developers, busy subreddits and communities that deal with a lot of reposts.
Thanks for taking a look!