[bernardohcr]

After years battling Google Workspace for cold outreach — bans, poor deliverability, expensive pricing, painful setup, and scaling issues — we decided to build the infrastructure we always wished existed.

We previously built and scaled TheChecker, an email deliverability SaaS used by Netflix, Mojang (Minecraft), and 6,000+ paying users worldwide. It was later acquired and became Emailable.

Now we’re building MailDock — a fully-managed, plug-and-play mailbox designed specifically for cold emailers.

It replaces Google Workspace seamlessly, with no changes to your existing workflow.

It’s like having a deliverability expert on call 24/7, monitoring, optimizing, and proactively fixing issues — for just $2/mo per mailbox.

We’re still early, but some tests showed very promising results and cost savings.

Would love your feedback, questions, and brutal honesty.

[m82labs]

I have no use for this but my first thought is wondering how safe the features like InfiniteSpin are from hallucinations. That’s assuming it’s using an LLM of course.

[bernardohcr]

The InfiniteSpin is optional and have a strict and extensive prompt that keeps the original structure, goal, and tone, but rephrases the message WITHOUT changing any important info like numbers, names, data, etc.

We only use latest LLM models. We used Claude 3.7 Sonnet (and are now updating to 4).

[collin128]

What kind of inboxes are they?

What has deliverability been like?

[bernardohcr]

Hey!

These are proprietary mailboxes. Yes, we’ve built an email server from scratch, so we could control and optimize every single layer of it, 100% focused on the inherent challenges of (legit) cold email at scale.

By being truly full-stack, we are able to automate a lot of stuff behind the scenes. I’m referring to things that are important, but very boring, technical, and time-consuming, so nobody actually do.

Example: instead of YOU manually monitoring blacklists and inbox placements in each mailbox, the system does that. If any issue is detected, it temporarily pauses sending from that mailbox and automatically increases warmup until it heals. Another example is rewriting each email to remove spam-trigger keywords and optimize other details (optional). That is done 100% automatically, so you can have way better results with zero maintenance work.

The system also has a dynamic sending queue for each ISP and takes into account the mailbox, domain reputation, and the most updated always-changing ISP rules.

These are only a few of the dozens of tiny optimizations we do, that compound into more sales.

The deliverability has been excellent, literally 100% based on daily inbox placement tests made over a week. We’re still optimizing some details before publish launch. Are you currently doing any cold email campaigns? If you want, it will be a pleasure to have a call and help with anything you need.