runsonwhat

Flex's tech stack

What does Flex use?

Flex (withflex.com) uses at least 17 tools we can see from public records, including Amazon Web Services for hosting, Google Workspace for email and documents, HubSpot for sales and Sanity for its website. Last checked .

“HSA and FSA payment marketplace for health and wellness products.”

Industry
E-commerce
Size
1–10 employees
Based in
Remote, United States
Founded
2023
LinkedIn
Company page
Re-check liveVisit withflex.com
Tools found
17
Categories
11
Layers
5 of 5
Last checked
Oct 2026

Flex's stack, layer by layer

Each tool links to the other companies we've found using it. The label says what kind of public trace gave it away.

Edge & Hosting

4 tools, where the bytes are served from

Hosting & Cloud

CDN & Edge

DNS

Application

3 tools, what the product is built with

Frontend

Auth & Identity

AI

Data & Observability

3 tools, what they measure and store

Monitoring

Go-to-market

5 tools, how they find and keep customers

Website & CMS

Marketing

Sales & CRM

Company Ops

2 tools, what the team runs on day to day

Workspace

Companies like Flex also use

Tools common among companies with a similar stack that we haven't found at Flex.

Companies with a stack like Flex's

Ranked by shared tools, with rare tools counting more.

Flex tech stack FAQ

What tools does Flex use?

We've found 17 tools at Flex (withflex.com). Edge & Hosting: Cloudflare, Amazon Web Services and Amazon Route 53. Application: Tailwind CSS and Clerk. Data & Observability: Sentry, web-vitals and Better Stack. Go-to-market: HubSpot, Klaviyo and LinkedIn. Company Ops: Google Workspace and Apple Business. Last checked October 2, 2026.

What cloud does Flex run on?

Flex uses Amazon Web Services and Vercel for hosting. We found Amazon Web Services through website code.

What CRM does Flex use?

Flex uses HubSpot for sales and CRM. We found HubSpot through email records and website code.

What email provider does Flex use?

Flex uses Google Workspace and Apple Business for email and documents. We found Google Workspace through email records and website code.

What CMS does Flex use?

Flex uses Sanity for its website. We found Sanity through website code.

What marketing software does Flex use?

Flex uses Klaviyo and LinkedIn for marketing. We found Klaviyo through DNS verification records.

Does Flex use Cloudflare?

Yes. We found Cloudflare at Flex through website code. Cloudflare is used by 569,071 companies we track.

How does runsonwhat know what Flex uses?

We read public traces only: Flex's DNS and email records, certificate logs, the code its website loads, and published subprocessor lists. A tool is listed only when a direct record backs it up. DNS is rechecked weekly and the website monthly.

We read public traces only: DNS and email records, certificate logs, website code and published subprocessor lists. A tool is listed when a direct record backs it up, and dropped when a recheck no longer finds it. Is this your company? See how to opt out.