I know this is an old question but a better solution is to set the flex item to align to the top using flex-start.
/* Default Styles */
.container {
display: flex;
}
.flexbox-2 {
flex: 2;
border: solid 3px blue;
height: 200px;
margin-left: 10px;
}
.flexbox-1 {
flex: 1;
align-self: flex-start;
border: solid 3px red;
}
<div class="container">
<div class="flexbox-1">"align-self: flex-start;"</div>
<div class="flexbox-2">.flexbox-2</div>
</div>