Blog post: Slippers blog template review (May 3)

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## Triage (REQUIRED)

The Inbound Marketing team prioritizes requests that drive results and meet our [goals of generating organic traffic and inquiries](https://about.gitlab.com/handbook/marketing/inbound-marketing/#goals). 

Please note that there is a different process for when you want to announce something via the blog. Please see [announcement requests](https://about.gitlab.com/handbook/marketing/corporate-marketing/#requests-for-announcements) in the handbook and open an announcement request issue instead of a blog post issue. 

Generally speaking, engineering blog posts that are tutorials/how-tos or which share how we built or debugged something, are popular with our audience. **If your proposed blog post is aligned with our [Attributes of a successful blog post guidelines](https://about.gitlab.com/handbook/marketing/blog/#attributes-of-a-successful-blog-post), you can skip straight to your [proposal](#proposal).** 

If you are pitching something outside of those guidelines, please fill in the below to help us prioritize. You can check out [examples of high- and low-performing blog posts to help with your rationale](https://about.gitlab.com/handbook/marketing/inbound-marketing/content/editorial-team/#top-performing-blog-posts). 

**This issue fulfills one of these goals:** <!--(Requestor check one)-->
- [ ] Drive traffic to our website
- [ ] Convert traffic into leads
- [x] Thought leadership/share expertise
- [ ] Build relationships with potential customers
- [ ] Drive long-term results (please explain below in your proposal)
- [ ] Announcement 
  - `Link to announcement request issue (required, see https://about.gitlab.com/handbook/marketing/corporate-marketing/#requests-for-announcements)`
- [ ] Cross-functional support 
   - `Link to OKR (required if this box is checked)` 
   
## Proposal

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The [digital experience team](https://about.gitlab.com/handbook/marketing/inbound-marketing/digital-experience/) recently launched the [new Slippers blog template](https://gitlab.com/gitlab-com/marketing/inbound-marketing/growth/-/issues/1146) for the marketing blog. 

I have two main points I'd like to write about, and I'd be happy to take feedback on which direction to pursue, or if it makes sense to write two separate posts, or if one post could contain both points.

1. We used GitLab's [iteration value](https://about.gitlab.com/handbook/values/#iteration), along with GitLab's tool to [promote an issue to an epic](https://docs.gitlab.com/ee/user/group/epics/manage_epics.html#promote-an-issue-to-an-epic) to iterate on an issue we realized was too large in scope by [promoting it to the blog post template epic](https://gitlab.com/groups/gitlab-com/marketing/inbound-marketing/-/epics/296). Once we did this, we were able to also [collaborate](https://about.gitlab.com/handbook/values/#collaboration) more effectively. I'd like to highlight how GitLab's iteration and collaboration values are embodied by the GitLab product's technical capabilities.
1. We had a problem where existing CSS was conflicting with the Slippers design system, and since we didn't have the header/footer ready yet, we couldn't just disable them all. So we used the [shadow DOM](https://developer.mozilla.org/en-US/docs/Web/Web_Components/Using_shadow_DOM) to encapsulate CSS entirely, along with [templates and slots](https://developer.mozilla.org/en-US/docs/Web/Web_Components/Using_templates_and_slots) to write semantic HTML in erb or HAML templates as desired, all tied together with [custom elements](https://developer.mozilla.org/en-US/docs/Web/Web_Components/Using_custom_elements). In addition to the values piece, I'd like to showcase how we used Web Components to solve challenges in a way that allowed us to iterate quickly. We have lots of the content [written as documentation](https://gitlab.com/gitlab-com/www-gitlab-com/blob/0c3b195ee49d4283fcb8330f987b3c039d0f2cff/doc/slippers-blog-template.md#L22), which could be rewritten in an approachable way for the blog.

## Roles and Responsibilities 
| Person | Role |
| ------ | ------ |
| `@tywilliams` | requestor | 
| `@person`| editor |
| `@person` | approver (optional) | 

### Checklist

- [ ] If you have a specific publish date in mind (please allow 3 weeks' lead time)
  - [ ] Include it in the issue title and apply the appropriate marketing milestone (e.g. `Mktg: 2021-03-28`)
  - [ ] Give the issue a due date of a minimum of 2 working days prior
  - [ ] If your post is likely to be >2,000 words, give a due date of a minimum of 4 working days prior
- [ ] If [time sensitive](https://about.gitlab.com/handbook/marketing/blog/#process-for-time-sensitive-posts)
  - [ ] Add ~"Blog: Priority" label and supplied rationale in description
- [ ] If wide-spread customer impacting or sensitive, mention `@nwoods` to give her a heads up ASAP, apply the ~"sensitive" label, and check the [PR handbook](https://about.gitlab.com/handbook/marketing/corporate-marketing/#requests-for-announcements) in case you need to open an announcement request instead of a blog post issue
- [ ] If the post is about one of GitLab's Technology Partners, including integration partners, mention `@dpduncan`,  apply the ~"Partner Marketing" label, and see the [blog handbook for more on third-party posts](https://about.gitlab.com/handbook/marketing/blog/index.html#third-party-posts)
- [ ] If the post is about one of GitLab's customers, mention `@FionaOKeeffe`, apply the ~"Customer Reference Program" label, and see the [blog handbook for more on third-party posts](https://about.gitlab.com/handbook/marketing/blog/index.html#third-party-posts)
- [ ] Indicate if supporting an event or campaign
- [ ] Indicate if this post requires additional approval from internal or external parties before publishing (please provide details in a comment)

## Production 
- [x] Requestor to complete issue template (Triage, Proposal, Roles and Responsibilities, Checklist )
- [ ] Issue sent through triage for consideration (approve, backlog, deny) 
- [ ] Issue assigned to requestor to draft blog post and open MR
- [ ] MR created and linked to issue - issue is now deprecated in favor of MR and will close once MR is complete

Story points: 2.0