Privacy Policy - Postbrew

Postbrew ("we," "our," or "us") operates postbrew.xyz (the "Service"). This Privacy Policy explains how we collect, use, disclose, and safeguard your information when you use our Service.

01Information We Collect

Account Info

Name and email (via WorkOS)
Unique user ID

Profile Data

Display name
Brewing preferences and defaults
Flavor preferences

Coffee Tracking Data

Brew logs (pour-over and espresso) with equipment, parameters, and feedback (Better/Worse ratings)
Baseline brews and dial-in experiments
Experiments and journals documenting brewing sessions
Coffee collection and personal notes
Tasting notes, descriptors, and brew insights

AI-Generated Data & User Feedback

Brew pattern analysis and suggestions generated by AI (Claude)
Personalized brewing recommendations based on your brew history
AI confidence scores and reasoning for suggestions
User feedback on suggestions (dismissed, acted upon, Better/Worse ratings)
Aggregated brewing patterns and outcomes across all users (anonymized)

How We Use AI Data to Improve Suggestions:

Real-time generation: Your brew data is sent to Anthropic's Claude API to generate personalized insights. This data is processed per Anthropic's data usage policy and is not used to train Claude models.
Internal analytics: We store your brew logs, AI suggestions, and your feedback (dismissed suggestions, Better/Worse ratings) in our database to improve suggestion quality for all users.
Aggregate learning: We analyze anonymized patterns (e.g., "85% of users who increased temperature on natural Ethiopian coffees marked it Better") to enhance AI prompts with community wisdom.
Future model training: We may use aggregated, anonymized brew data and feedback to fine-tune our own AI model in the future, giving us full control over learning from Postbrew-specific brewing patterns. If we do this, we will update this policy.

Technical Telemetry

Session cookie (7-day expiration, stored in httpOnly cookie)
IP address (temporarily for rate limiting only)
Analytics via Google Analytics and ContentSquare (anonymous usage data)

02Usage Protocols

Provide coffee tracking, brew logging, and AI-powered insights
Generate personalized AI brew suggestions based on your history
Detect brewing patterns and provide extraction science guidance
Improve AI suggestion quality for all users by analyzing aggregated, anonymized brew data and feedback
Enhance AI prompts with community-validated brewing insights (e.g., "most users found higher temps work better for natural process coffees")
Potentially fine-tune our own AI model in the future using anonymized data to improve suggestion accuracy
Authenticate your account and manage sessions
Analyze anonymous usage patterns to improve the Service
Prevent abuse and spam

Strict Prohibitions (We do NOT):

Sell your personal information
Use your data for advertising
Track you across other websites
Share your private content without permission

03Data Usage for AI Improvement

Postbrew learns from the coffee community to provide better suggestions for everyone. Here's exactly how we use your data:

1What Data We Collect for AI Learning

Brew logs: Parameters (temp, dose, grind, time), coffee type (origin, process, roast), and your tasting notes
User feedback: Better/Worse ratings, dismissed suggestions, and which suggestions you acted upon
AI-generated content: Suggestions created, confidence scores, and pattern types detected
Brewing outcomes: Whether parameter changes led to better or worse results

2How We Use It (Current)

Pattern detection: Your complete brew history is sent to Claude API to generate personalized suggestions specific to your brewing journey
Internal storage: We store all brew data, suggestions, and feedback in our Supabase database for your personal tracking and future analysis
Aggregate analytics: We analyze anonymized patterns across all users (e.g., "Natural Ethiopian coffees respond well to higher temps") to improve AI prompt engineering
Suggestion refinement: Community-validated insights are incorporated into AI prompts to provide more accurate, coffee-science-backed recommendations

3Future Plans: Model Fine-Tuning

We plan to fine-tune our own AI model using aggregated, anonymized data from the Postbrew community. This will allow us to:

Learn from community-validated brewing patterns specific to Postbrew users
Provide more accurate suggestions based on real-world outcomes (not just theory)
Understand coffee-specific nuances (e.g., how Kenyan AA responds differently than Colombian Supremo)
Reduce reliance on third-party AI services and have full control over the suggestion engine

Privacy Protection:

Any model training will use aggregated, anonymized data only. Your specific brew logs will never be identifiable in the model. For example: "500 users tried higher temps on natural Ethiopians, 85% marked Better" (not "User X did Y").

4Your Control

You can dismiss or hide any AI suggestion at any time
You can delete your brew logs, which removes them from your personal history
Aggregated patterns may persist in anonymized form (e.g., community statistics)
You can opt out of AI suggestions entirely in your settings
If you delete your account, all personally identifiable data is removed (aggregated, anonymized statistics may remain)

04Visibility Controls

Your Data is Private

All of your brewing data is private by default and only visible to you:

Email address
Brew logs (all brew data is private)
AI suggestions and brew insights
Experiments and journals
Coffee collection and notes
Account settings and preferences

Aggregated, Anonymous Data Only

The only "public" data is aggregated, anonymized patterns used to improve AI suggestions:

Community brewing patterns (e.g., "85% of users marked higher temps Better for natural Ethiopians")
Anonymous usage analytics (Google Analytics, ContentSquare)

Your specific brew data is never identifiable in these patterns.

System Note: Postbrew is a private brewing lab, not a social network. All your data stays with you.

05Third-Party Subsystems

We use the following trusted services:

WorkOS

Authentication & Identity

Supabase

Database & Storage

Anthropic (Claude AI)

AI Brew Pattern Analysis

Google Analytics

Anonymous Usage Analytics

NO Personalized Ads. NO Cross-Site Tracking. NO Data Selling.

06User Rights

Access: View all information associated with your account
Update: Edit your profile, brew logs, and content at any time
Delete: Remove brew logs, AI suggestions, experiments, journals, and notes
Dismiss AI Suggestions: Dismiss or hide AI-generated brew insights at any time
Opt Out: Disable AI suggestions entirely in your settings
Export: Request a copy of your data (contact us)
Delete Account: Request complete account deletion (contact us)

System Note: Account deletion is not currently available through the interface. To delete your account and all data, please contact us directly.

07Contact

Website: https://postbrew.xyz

Email: avi@postbrew.xyz