Show HN: Anchor Relay – A faster, easier way to get Let's Encrypt certificates
23 geemus 23 8/20/2025, 4:13:18 PM anchor.dev ↗
From the cryptic terminal commands to the innumerable ways to shoot yourself in the foot, I always struggled to use TLS certificates. I love how much easier (and cheaper) Let's Encrypt made it to get certificates, but there are still plenty of things to struggle with.
That's why we built Relay: a free, browser-based tool that streamlines the ACME workflow, especially for tricky setups like homelabs. Relay acts as a secure intermediary between your ACME client and public certificate authorities like Let's Encrypt.
Some ways Relay provides a better experience:
- really fast, streamlined certificates in minutes, with any ACME client
- one-time upfront DNS delegation without inbound traffic or DNS credentials sprinkled everywhere
- clear insights into the whole ACME process and renewal reminders
Or read our blog post: https://anchor.dev/blog/lets-get-your-homelab-https-certifie...
Please give it a try (it only takes a couple minutes) and let me know what you think.
* If you want an SSL certificate for, say, your printer
* And you don’t want to expose your printer’s port 80 to the public internet because you’re not stupid
* And you don’t want to put your DNS credentials onto your printer either, because again, you’re not stupid
* And you don’t want to pay for a certificate with a longer validity, because it’s a home printer, so you’re stitch with monthly cert rotations
* And you’ve embraced the reality that one can delegate SSL not just to CAs, but also to other third parties. Usually the likes of AWS & cloudflare - but why stop there?
Then this product is what you need!
[1]: https://github.com/FiloSottile/mkcert
Ummmm why does my printer need a certificate?
You get a handful of somewhat questionable benefits. If for some reason your guests are visiting your printer's administration page, they won't have to click through a scary warning page. If someone is somehow sniffing all the traffic within your home network they won't be able to get your printer's administrative password.
But the main reason is some homelab enthusiasts are like bodybuilders at the gym - taking on tasks that seem Sisyphean to outsiders, for fun and to build their strength.
...then (at least in theory!) there's no reason to not also give every one of those devices, with their public-routable IPv6 addresses, a stable public-rooted name — i.e. a DNS FQDN.
Mind you, none of the infrastructure to make this work exists.
For example, while DDNS exists, it really only exists to assign your gateway router itself a name — with the expectation being that you're using NAT, and then having your router port-forward any interior services to masquerade them as being services of the router.
A theoretical "DDNSv6", meanwhile, would instead expose your entire LAN as AAAA records under your DDNS suffix — much like how e.g. `tailscale share` exposes devices as device.yournetwork.ts.net. But using plain public-routed IPv6, rather than proprietary overlay routing.
The problem with this being that neither routers nor IoT devices have any way to assign DNS-like names to devices on your network. So where would these device names come from? (If it were me, I'd have the router observe mDNS announcements from these devices, and then suffix-replace `.local` in the mDNS name with the configured DDNS suffix to build AAAA records. But even then, some devices don't even do mDNS!)
And then, even if you do that, there's still nowhere for the TLS cert for your printer to live under this scheme. The printer itself has no concept of speaking TLS. (Why would it? It expects to only ever be local-segment routable, and for physical access to the network segment to be the sum total of its security mechanism.) To work around this, you'd need your gateway router to do L7 IPv6 routing (imagine if your router worked like Cloudflare DNS, where you could "orange cloud" your LAN devices) so that the router itself could 1. force itself as the default route for the device, even for LAN-to-LAN packets; and then 2. terminate the TLS connection if the device is being spoken to on port 443; but just act as a dumb passthrough otherwise.
a) impersonate the identities of your users and b) decrypt the SSL traffic of your users
?
Anchor never see sees your private keys for certificates.
We hold an ACME account key on your behalf with the CA, but we cannot use it impersonate your domain or decrypt traffic.
We have a more technical overview of how this works in our docs: https://anchor.dev/docs/public-certs/acme-relay
That makes no sense whatsoever. If you have an ACME account key for my domain, of course you can use it to impersonate my domain. You just need to create another certificate. (Which I could detect, but if I know how to do that, I'm probably not going to need your service anyway.)
Whether or not something like this makes sense to you is probably a question of your personal threat model.
I'm sorry. But do you really need to re-invent the wheel yet again ?
Go to the Let's Encrypt website, there is a whole page of client implementations[1].
What makes yours better than, for example, `lego` or `caddy` or `step` ?
All of which are easy to use, come with sensible defaults and do not provide you with "innumerable ways to shoot yourself in the foot".
And for people who really can't use Let's Encrypt because "its difficult", there are still all the old-school, well-established, commercial CA's out there who will hold your hand in return for a few dollars.
[1] https://letsencrypt.org/docs/client-options/
1. Install acme-dns somewhere
2. Point part of your domain to that
3. Use lego or caddy or whatever to get certs using dns-01
No need to pay some dude who can then forge certs for your domain.