That’s a lesson 22-year-old Isis Wenger recently learned the hard way after a marketing campaign for her employer featured her along with two of her coworkers. Wenger is an engineer at OneLogin, a company that helps people manage their online passwords, and the ad, displayed at some San Francisco subway stations, included a photo of her wearing a company t-shirt. It drew both support and criticism on social media, which prompted Wenger to write a post on Medium about the experience.

So what were detractors not happy with?

Mostly that Wenger doesn’t “look” like an engineer — or rather, whatever stereotypical image of one they hold. In their minds, a young, attractive woman couldn’t possibly be an engineer, or the company must have picked her in order to appeal to mostly-male pool of potential candidates around town who might want to work at OneLogin someday, they argued.

Wenger published her blog post over the weekend, which included a call for women to share their experiences as female engineers on social media using the #ILookLikeAnEngineer hashtag to break the stereotypes.

Here are some of the posts on Twitter:

https://twitter.com/thephysicsgirl/status/628649860024004608

https://twitter.com/daraoke/status/628625476051861504

https://twitter.com/EricaJoy/status/628387591478378496

I'm the lead on @digitalocean's web team and I love speaking at conferences. Also, cupcakes. #ILookLikeAnEngineer pic.twitter.com/ambWqWgHlN

— jenna (@zeigenvector) August 3, 2015

https://twitter.com/aredridel/status/628332938615226368

https://twitter.com/marcosc/status/628367326572843009

https://twitter.com/hopefulcyborg/status/628331124113186816