For eighteen years at Roche I was on the inside of enterprise internal communications — not writing about it, running it. I made the business case for a campaign platform, introduced it, and scaled it until it was carrying more than twenty million messages a year for over six hundred teams, at under a fifth of what the incumbent tools cost. I trained and coached more than a hundred markets on it. And because it was pharma, GDPR and pharmacovigilance obligations were architected in from day one rather than retrofitted after an audit.
So I know exactly what this job is. The all-hands email. The reorganisation announcement. The benefits change that half the company will misread unless the second paragraph is exactly right. Not campaigns — correspondence, to people who already work here and cannot unsubscribe from their employer.
And I know what the tools get wrong, because I spent nearly two decades working around it. They are marketing tools. Every assumption inside them was built for reaching strangers who might buy something: upload the contact list, score the engagement, segment the audience, find out who didn't open it. Aimed at customers, those are ordinary features. Aimed at your own colleagues, the last one stops being a metric.
“Can you send me the list of who hasn't opened it yet?” is a reasonable question in marketing and a disciplinary one in a company.
I have been asked that question. I understand why people ask it — they are usually anxious, not malicious, and they want to know the message landed. But the honest answer is that a tool which can produce that list will eventually be made to produce it, by someone more senior than whoever said no the first time. The protection has to be in the architecture, not in the policy.
So I did what I have always done — in 1997 it was a CorelDraw script engraving circular text onto copper trays, and the instinct never changed: find the step no human should repeat by hand, then build the thing that removes it. I built my own. It sent from the sender's real mailbox, using the company's own accounts, and it worked well enough that people asked me for it. Then I left, and it stayed behind — wired to an account that was no longer mine. I could not take it with me, and the people using it could not keep it running.
SlipperySign Mail is that tool, rebuilt properly. Same core idea — the mail leaves your mailbox, not ours — but this time built as a real product, on infrastructure I own, with the privacy guarantees written into the database schema instead of into a promise on a website.
Most product people learned systems thinking from a course. I built the systems first, and did the job titles afterwards — sysadmin, webmaster, developer, full-stack lead, project manager, business analyst, product owner. Eight titles, one underlying capability: see the system inside a scattered mess of pieces, propose the version worth building, then build it so the next person can extend it without friction.
These are not features chosen from a competitor's checklist. Each one exists because of a specific bad afternoon.
“Why does this say noreply?”
An announcement about people's jobs, arriving from an address nobody can answer. Staff read the sender line before the subject, and a relay address tells them this is broadcast, not conversation.
So it sends from the real person's mailbox, and replies go back to them.
“Who hasn't read it?”
Asked in good faith, usually by someone who just wants reassurance. But once the report exists it becomes evidence, and comms is not in the business of supplying evidence about colleagues.
So there is no recipient column in any tracking table. The report cannot be built.
“Can you send me the staff list?”
Every marketing tool starts by asking you to upload your people. That list is the most sensitive file the company has, and it should never sit in a vendor's database in order to send an email.
So campaigns go to the distribution lists you already run. Nothing is uploaded.
“Who deleted the legal line?”
Someone in a hurry, at 17:40, on the template everyone copies. By the time it is noticed it has gone to twelve thousand people and the correction email is worse than the mistake.
So regions can be locked, and approval blocks the send until a named person signs off.
“It looked fine when I sent it.”
It did — in the preview. Then Outlook rendered it, and the carefully built layout collapsed into a single column with the logo three times too large.
So the output is MJML, which is built specifically to survive Outlook.
“We're over our contact limit again.”
A price that moves every time the company hires, for a tool that is sending to one distribution list. The bill grew with headcount for no reason connected to the work.
So there is one flat monthly rate by company size, and no volume charging at all.
You are evaluating software from someone you have not met. Here is the part a sales page would leave out.
I build it, I support it, I answer the email. That means you get a direct line to the person who wrote the code — and the person who has actually run a platform at your scale — but it also means I am not a company with a 24/7 support desk. Judge that honestly against what you need.
I store senders, collaborators, admin addresses, the lists you save and an audit log. The what we store section prints all of it, by database column, including the ones people usually hide.
It sends internal email beautifully and it does nothing else. No intranet, no chat, no employee app, no survey suite. If you want one vendor for all of it, this is the wrong product.
Because your own mailbox does the sending, your own Gmail or Microsoft 365 limits apply. That is the trade for never being the sender — and it is the trade that makes the rest of it possible.
If any of the above sounded like your job, the tool was built for you specifically.
Open the app
SlipperySign