head to head · open source
BillionMail vs ktx
BillionMail has 15,619 GitHub stars, 1,704 forks, 239 open issues and last shipped 3 months ago. ktx has 1,598 stars, 105 forks, 52 open issues and last shipped 9 days ago. BillionMail leads on adoption by 877% (15,619 vs 1,598 stars). BillionMail is written in Go under AGPL-3.0; ktx is written in TypeScript under Apache-2.0. BillionMail has attracted 11% as many forks as stars, ktx 7%. ktx was the more recently maintained of the two, and both are self-hostable with no licence fee.
Two open source projects, one decision. Both are free and self-hostable — the differences are community size, license terms, language stack and release pace.
← all 20902 open source comparisons
Side by side
| BillionMail | ktx | |
|---|---|---|
| GitHub stars | ★ 16K | ★ 1.6K |
| License | AGPL-3.0 | Apache-2.0 |
| Written in | Go | TypeScript |
| Last push | 2026-06-11 | 2026-09-11 |
| Forks | ⑂ 1.7K | ⑂ 105 |
| Self-hosting | Yes | Yes |
| Data ownership | Your server | Your server |
pick BillionMail if
- You weight community size — 16K stars and counting
- You want the AGPL-3.0 license terms
- Your stack matches Go
- You value the larger contributor base for long-term maintenance
pick ktx if
- You want the ktx feature set and don't need the biggest community
- You prefer the Apache-2.0 license terms
- Your stack matches TypeScript
- You evaluated both and ktx fits your workflow better
About BillionMail
BillionMail is an open source mail server, newsletter, and email marketing platform that runs entirely on infrastructure the operator controls. It is written in Go and released under the AGPL 3.0 license, and it lives in the self hosted email and marketing ecosystem alongside the mail transfer and delivery components it bundles, including Postfix, Dovecot, and Rspamd. The project ships as a complete stack rather than a single binary, combining a sending server, a campaign manager, and a webmail client so that one deployment covers transactional mail, promotional campaigns, and newsletters.
read the full BillionMail overview →
About ktx
ktx is an open source, Apache 2.0 licensed executable context layer, built and maintained by Kaelio in TypeScript, that lets AI agents such as Claude Code, Codex, Cursor, and OpenCode query analytical warehouses accurately using approved metric definitions, detected joinable columns, and company knowledge.
More in Business Software
Related comparisons
More Marketing & Customer Engagement projects
Compare either of these against the rest of the Marketing & Customer Engagement field.
Frequently asked questions
Is BillionMail or ktx more popular?
BillionMail has 15,619 GitHub stars and ktx has 1,598. BillionMail has the larger community by that measure.
Are BillionMail and ktx free?
Both are open source. BillionMail is licensed under AGPL-3.0 and ktx under Apache-2.0. Neither carries a licence fee.
What is the difference between BillionMail and ktx?
BillionMail is written in Go and ktx in TypeScript. The practical differences are community size, licence terms, language stack and release cadence — all compared in the table above.
Which should I choose, BillionMail or ktx?
Choose BillionMail if you want the larger community (15,619 stars) or its AGPL-3.0 licence terms. Choose ktx if its feature set, stack or Apache-2.0 licence fits better. Both are self-hostable.