head to head · open source
Billion Mail vs ktx
Billion Mail has 15,619 GitHub stars, 1,704 forks, 236 open issues and last shipped 3 months ago. ktx has 1,598 stars, 105 forks, 52 open issues and last shipped 9 days ago. Billion Mail leads on adoption by 877% (15,619 vs 1,598 stars). Billion Mail is written in Go under AGPL-3.0; ktx is written in TypeScript under Apache-2.0. Billion Mail 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.
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Side by side
| Billion Mail | 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 Billion Mail 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 Billion Mail
BillionMail is an open source mail server and email marketing platform written in Go and released under the AGPL 3.0 license. It lives in the self hosted email ecosystem and is described as a solution for newsletters, promotional emails, and transactional messages. The project combines mail server topics such as Postfix, Dovecot, Rspamd, and SMTP with campaign features such as customer management, analytics, templates, and sending control.
read the full Billion Mail 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.
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Frequently asked questions
Is Billion Mail or ktx more popular?
Billion Mail has 15,619 GitHub stars and ktx has 1,598. Billion Mail has the larger community by that measure.
Are Billion Mail and ktx free?
Both are open source. Billion Mail is licensed under AGPL-3.0 and ktx under Apache-2.0. Neither carries a licence fee.
What is the difference between Billion Mail and ktx?
Billion Mail 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, Billion Mail or ktx?
Choose Billion Mail 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.