# How thredUp uses Harness

As published on [harness.io](https://www.harness.io/case-studies/powering-record-black-friday-deals-at-thredup), August 2026. Captured by usedby on 2026-10-07.

- Company: [thredUp](https://www.usedby.ai/companies/thredup.md)
- Tool: [Harness](https://www.usedby.ai/tools/harness.md)
- Teams: Engineering, Customer Service, Product

## What the story says

thredUp uses Harness feature management (formerly Split) for phased feature rollouts, real-time personalization of Black Friday promotions, backend A/B testing, and hidden production features for internal QA.

Summary written by usedby from the source page, in English. The figures are those of Harness and thredUp, not ours.

> Personalize Offers in Real Time: During Black Friday, Split enabled thredUP to dynamically serve unique promotions and experiences based on customer attributes and machine-learning scores.

> If we built this in-house, it would have required a whole team. Split had everything we needed out of the box—developer-friendly, intuitive UI, and robust data capabilities.
>
> Dan DeMeyere, VP Engineering

## What usedby checked

We compared the story with its live page on 2026-10-07.

- Checked: the passage quoted above is copied word for word from the page, near the name of thredUp.
- Checked: the publication date is read from the page’s own metadata, never guessed.
- Checked: thredUp uses Harness. Confirmed line. Latest check across sources: 2026-10-07.
- Not checked: the result itself. We quote it; we did not measure it.

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Source: https://www.usedby.ai/case-studies/thredup-harness · How we check: https://www.usedby.ai/methodology