photo of Katarina Rosiak

Katarina Rosiak

Software Engineer

I’m a full-stack Software Engineer with experience with JavaScript, Node.js, PostgreSQL, React, and AWS. Passionate about creative problem solving and always eager to learn new technologies.

Recently I co-created Seymour , an open-source, AWS-native active monitoring solution specializing in API testing from globally distributed locations.

An image showing Seymour's architecture


Seymour is an open-source and easy-to-configure active monitoring solution that allows users to simulate requests from globally distributed locations to test their API endpoints. For each test, Seymour measures the availability, response time, and correctness of the API endpoint response.

Our team built Seymour to help engineering teams bolster existing testing approaches and handle the challenges of monitoring their increasingly complex systems. Seymour aims to detect issues in production before users experience them and provides geographic distribution of tests, allowing users to configure tests originating from 22 global locations.


Deploying Seymour requires two CLI commands. Once it is set up, Seymour provides a UI for configuring and viewing all tests and alerts, along with an API for programmatic configuration.

  • React
  • PostgreSQL
  • Express
  • AWS
  • EventBridge
  • Lambda
  • SQS
  • SNS
  • ElasticBeanstalk
  • EC2

READ SEYMOUR'S CASE STUDY

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