A clever watermarking technique that went viral

How Bluesky draws its logo on screenshots

Based on Hacker News Discussion

469 points

02

The Discovery

What happens when you take a screenshot on Bluesky

Bluesky's Hidden Feature

01

Automatic watermarking Bluesky subtly draws its logo on every screenshot captured by users
02

Invisible to the eye The watermark is nearly imperceptible during normal viewing
03

Viral revelation The discovery sparked widespread discussion across social media platforms
04

Attribution tracking Helps identify the source of shared screenshots

The Watermarking Process

1

Screenshot captured

User takes a screenshot within the Bluesky app

→

2

Logo drawn

App renders the Bluesky logo onto the screenshot image

→

3

Subtle embedding

Logo is embedded with low opacity and strategic positioning

→

4

Image saved

Screenshot includes the hidden watermark marker

05

Technical Details

Understanding the implementation

Implementation Approach

Bluesky achieves this through clever use of UI layer rendering. When a screenshot is detected, the app draws a semi-transparent logo overlay onto the captured image. The technique leverages native screenshot APIs to intercept and modify the image before it's saved to the user's device.

• Utilizes native screenshot detection APIs

• Renders logo as a semi-transparent overlay

• Preserves visual quality of original content

• Works across both iOS and Android platforms

A simple yet effective approach

Why This Matters

visibility

Attribution

Helps trace the origin of viral screenshots back to Bluesky

security

Authenticity

Distinguishes genuine screenshots from fabricated content

share

Brand Reach

Every shared screenshot becomes free marketing for Bluesky

balance

Privacy Balance

Achieves tracking without compromising user experience

Thank You

A clever innovation in screenshot attribution

Source: timmarinin.net/2026/bluesky-screenshots/