Why sponsor it
SenderFinder exists because the tools that used to answer “who is this sender?” kept disappearing. Rapportive was acquired and shut down. Clearbit Connect stopped working on 30 April 2025. The replacement is an AGPL-3.0 extension that runs in your browser, uses your own provider keys, and has no SenderFinder account or server in the lookup path.
That architecture is cheap to run and expensive to maintain. There is no subscription to fund it. The provider adapters have to follow catalog and API changes. The benchmark costs money every time it runs because it calls paid provider APIs. Ten UI languages have to be kept in step with every new string. Sponsorship is what turns “someone maintains this in their spare time” into “someone can keep maintaining it”.
Sponsorship is not a vote on the roadmap. The project's value is that it recommends the cheapest step first and says when it is uncertain; a sponsor cannot buy a different answer.
What sponsors get
Sponsorship is recognition, not advertising inventory. The current offer is deliberately small and concrete:
- A logo and a link on this page, in the sponsors section, once there are sponsors to list.
- A logo and a link in the repository's README.md, next to the project description.
- A one-line description of what you do, if you want one, in both places.
- The honest association with an open-source tool that does not collect inbox data and publishes its benchmark methodology.
What sponsorship does not buy: placement in the extension's About card (that is not offered and should not be assumed), a provider ranking, a favourable benchmark result, a roadmap commitment, access to user data, or the right to approve copy. The project has no user data to sell and no interest in inventing some.
Current sponsors
There are none yet. This project has no sponsors and no paid tier at the time of writing. The section above describes what will be offered when there are; it is not a disguised list of existing supporters.
If that changes, the names will appear here and in the README, with the date they started. No placeholder logo is shown in the meantime.
Provider relationships, disclosed
SenderFinder depends on three data providers. Two aggregate several sources behind one key; the third is an optional fallback. They are commercial services, and the project's relationship with them should be as legible as the lookup path.
The extension never calls a data source directly. BlitzAPI, QuickEnrich and Village are called through treg; Hunter, Apollo and ContactOut through Monid; Data Legion through Firecrawl. An Apollo API key of your own does nothing here, because the request goes through Monid. That is an architectural fact, not a sponsorship claim.
| Provider | What it powers | Relationship |
|---|---|---|
| treg | BlitzAPI, QuickEnrich, Village | No referral parameter is documented in the repository. |
| Monid | Hunter, Apollo, ContactOut | No referral parameter is documented in the repository. |
| Firecrawl | Data Legion fallback | Referral link firecrawl.link/sf, documented in CHANGELOG.md. |
If you sign up through a provider link in the extension and the provider pays a referral fee, that fee goes to the project. It does not change the waterfall order, the prices shown in settings, or the benchmark. The table is updated when a relationship changes.
How to sponsor
The GitHub Sponsors page is being set up. Until it is live, the practical route is to open an issue on github.com/astonysh/SenderFinder with the subject “sponsorship” and say what you have in mind — one-time, recurring, or in kind (benchmark provider credits are especially useful). The maintainer will reply with a way to contribute.
You can also write to tony@senderfinder.com. GitHub issues remain the public, durable channel; please do not send keys, addresses or other personal data in either.
If you are a provider and want to donate API credits for benchmark runs, say so in the same issue. Credits are used only for the published benchmark, and the methodology and results stay public.
Where the money goes
Benchmark runs are the clearest cost: a 50-address run against paid provider APIs costs money every time, and reruns are how the price and hit-rate tables stay honest. The rest is maintenance time — provider adapters, the Outlook path, the ten UI languages, the install guide and the privacy statement.
When sponsorship starts, a short use-of-funds note will be published here with the same date as the sponsor list.
What we will not do
- Sell or share lookup data. The extension has no server in the lookup path and no inbox database.
- Put a sponsor's provider first in the waterfall, or hide a cheaper step behind a sponsorship.
- Publish a benchmark result a sponsor paid to change. Reruns may change the numbers; the method does not.
- Add tracking to this website. The site loads no analytics script and no third-party requests.
- Promise a feature that is not in the repository. The code is the roadmap.
Related reading
- The 50-address benchmark — the numbers sponsorship helps keep current.
- Usage statistics — what the project counts, and what it does not.
- Privacy statement — the data model in full.
- Install guide — the free product this supports.
- Clearbit Connect alternative and Rapportive alternative.