Open source projects work diligently to fix all the vulnerabilities. Why shoundn't your project be powered with the knowledge of when and where theses apps to eradicate them? All those below can shield your project and monitor your project for publicly disclosed security vulnerabilities, and it is free as well.

1. TestQuality

TestQuality's GitHub Test Management extends Github to provide powerful and modern test plan management helping developers and testers create, run, coordinate and monitor software testing tasks. TestQuality is FREE for GitHub public repo’s and affordable for private repo's.
https://github.com/marketplace/testquality

2. ImgBot

Optimizing images yourself is time consuming, let ImgBot do all the heavy lifting for you. You just sit back and review the PRs.
https://github.com/marketplace/imgbot

3. Circle-ci

Let CircleCI help your team focus on making a great product. Speed up your test and delivery cycle and improve productivity, without running your own infrastructure.
https://github.com/marketplace/circleci

4. CodeTree

Codetree is a lightweight project management app with terrific support for multi-repo projects. There's nothing to install and it works in every browser.
https://github.com/marketplace/codetree

5. Gitpod.io

Gitpod is the online IDE for GitHub. It launches a complete dev environment for any GitHub project, by simply prefixing the GitHub URL with gitpod.io.
https://github.com/marketplace/gitpod-io

6. WakaTime

Tracking the time that you spend on coding, and you can even setup a goal each day.
https://github.com/marketplace/wakatime

7. Buddy

Automatically build & ship web projects on a single git push, on click, or recurrently. Easily define your own delivery process just like you build a house of bricks: from builds and tests, to deployments, custom scripts, and website monitoring.
https://github.com/marketplace/buddy

8. Depfu

Depfu is the best way for busy teams to keep their app dependencies up-to-date. We believe doing small, easy to assess updates regularly and supported by automation is a lot easier than falling behind and having to update everything at once.
https://github.com/marketplace/depfu

9. Moesif API Insights

Moesif is the most advanced AI-powered API analytics and debugging service designed specifically for production APIs including RESTful, GraphQL, Ethereum Web3, and SOAP APIs.
https://github.com/marketplace/moesif-api-insights

10. DeepAffects

DeepAffects is a team dynamics analytics application, for managers & team leads, to get issue-level emotional insights, to increase team dynamics & productivity.
https://github.com/marketplace/deepaffects