Developer builds AWS-powered dog detector app scoring 20/20 in weekend challenge

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A developer built a webcam-based image classifier called 'Dog or Not: Lite' for the AWS Weekend Challenge, using Amazon Nova Lite via the Bedrock Converse API and deploying it on Amazon Lightsail in us-east-1. The app, built on FastAPI with Python 3.13, achieved a perfect 20/20 score on its test set with a median response time of 880 milliseconds per scan. The entire backend runs in just 285 lines of code with no build step or frontend framework, using a single HTML page and one API endpoint. The developer documented several AWS-specific pitfalls, including Lightsail's lack of IAM task roles requiring credentials via environment variables, cross-region inference profile authorization issues, and silent architecture mismatches when deploying non-amd64 container images. The app's classification logic is deliberately strict, recognising only living domestic dogs as true positives and excluding wolves, toys, statues, and costumes.

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