Fastmail's tech stack
What does Fastmail use?
Fastmail (fastmail.fm) uses at least 8 tools we can see from public records, including Fastmail for email and documents, PostHog for analytics, web-vitals for monitoring and Workable for hiring and HR. Last checked .
- Company page
- Tools found
- 8
- Categories
- 6
- Layers
- 3 of 5
- Last checked
- Nov 2026
Fastmail's stack, layer by layer
Of 8 tools, 4 came from website code, 2 from DNS records and 2 from email records. 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
1 tool, where the bytes are served from
CDN & Edge
Data & Observability
2 tools, what they measure and store
Monitoring
Analytics
Company Ops
5 tools, what the team runs on day to day
Workspace
People & HR
Security & Compliance
Companies like Fastmail also use
Tools common among companies with a similar stack that we haven't found at Fastmail.
Companies with a stack like Fastmail's
Ranked by shared tools, with rare tools counting more.
Pobox is now part of Fastmailpobox.com8in common
Fastmailfastmail.help4in common
Lanes GroupUtilities · 1,001–5,000 people1in common
Keeper Securitykeepersecurity.com3in common
Reverse TechHealth, Wellness and Fitness · 11–50 people2in common
Wavestrong, Inc.IT Services · 201–1,000 people1in common
ProcookRetail · 201–1,000 people3in common
Skrice Studios, Inc.Software · 51–200 people2in common
Fastmail tech stack FAQ
What tools does Fastmail use?
As of November 2026, runsonwhat has found 8 tools at Fastmail (fastmail.fm) in public records. Edge & Hosting: Cloudflare. Data & Observability: web-vitals and PostHog. Company Ops: Let's Encrypt, DigiCert and Red Sift OnDMARC. Last checked November 9, 2026.
What email provider does Fastmail use?
Fastmail uses Fastmail for email and office software, according to runsonwhat (November 2026). runsonwhat found Fastmail through email records that authorize Fastmail. Fastmail is used by 1,284 companies runsonwhat tracks.
What analytics tools does Fastmail use?
Fastmail uses PostHog for analytics, according to runsonwhat (November 2026). runsonwhat found PostHog through PostHog code on fastmail.fm. PostHog is used by 10,992 companies runsonwhat tracks.
What does Fastmail use for hiring and HR?
Fastmail uses Workable for hiring and HR, according to runsonwhat (November 2026). runsonwhat found Workable through Workable code on fastmail.fm. Workable is used by 971 companies runsonwhat tracks.
What monitoring tools does Fastmail use?
Fastmail uses web-vitals for monitoring, according to runsonwhat (November 2026). runsonwhat found web-vitals through web-vitals code on fastmail.fm. web-vitals is used by 29,889 companies runsonwhat tracks.
Does Fastmail use Cloudflare?
Yes. runsonwhat found Cloudflare at Fastmail through Cloudflare code on fastmail.fm. Cloudflare is a CDN & Edge tool used by 736,485 companies runsonwhat tracks.
Which companies have a tech stack similar to Fastmail's?
The companies with the stacks most like Fastmail's are Pobox is now part of Fastmail, Fastmail, Lanes Group and Keeper Security, according to runsonwhat (November 2026). Each shares 1 to 8 tools with Fastmail, and rare tools count for more than common ones like Google Workspace, so the match reflects real stack choices.
How does runsonwhat know what Fastmail uses?
runsonwhat reads public records only. Of the 8 tools at Fastmail, 4 were found through code on fastmail.fm, 2 through DNS records and 2 through email records. A tool is listed only when a direct record backs it up; DNS is rechecked weekly and fastmail.fm about 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.