The promise, stated precisely
Your LinkedIn session never leaves your machine. You log in inside a browser window that belongs to the application; the cookies live in that window's own storage, on your disk. We never see your password, and the session is never transmitted to us — not encrypted, not "securely", not at all.
That is a narrower claim than the one most tools in this category make, and it is narrower on purpose. "All your data stays local" would be a nicer sentence and it would be false, because some things do leave. They are listed below.
The difference matters in practice: a cloud tool logs into LinkedIn from a data-centre address, on infrastructure shared with everyone else on that platform. Booost acts from your computer, your network, your session. That is the whole architectural argument, and it is the reason the anti-ban system can work the way it does.
What stays on your disk
- The LinkedIn session and cookies. Never transmitted.
- Your LinkedIn password. Never seen — the login happens inside the app's browser window, between you and LinkedIn.
- The database. Contacts, enrichment, conversations, drafts, campaign history, analytics, workflow definitions: one SQLite file on your machine. You can copy it, back it up, or delete it.
- Your AI keys, on the Basic edition. Stored locally and used locally.
What leaves, and why
Six things. Each one has a reason, and three of them can be switched off.
1Your account and subscription
Email, subscription state, and the number of active managed accounts — the last one because the price is per account and Stripe needs a quantity. No LinkedIn data is attached to it.
2A presence heartbeat
At boot, then every five minutes only if something actually happened since the last beat — not a fixed ping. It carries whether the LinkedIn session is healthy (a yes/no, never the session itself), and the app version and OS release.
It exists so the cloud dashboard can tell you an account has gone quiet without you having to open the desktop.
3A snapshot of what is scheduled
This is the one to read carefully, because it is the least obvious.
| What is sent | Contents |
|---|---|
| Scheduled posts | when it is due, its editorial status, and the first 140 characters of the body |
| Cron workflows | the workflow's name, when it next runs, its status |
| Comments awaiting review | a count, not the comments |
So: an excerpt of a scheduled post does leave your machine. 140 characters, capped in code, and only for posts that are actually scheduled — a draft you have not scheduled is not in the snapshot. It is there so the dashboard can show you "this goes out at 9am" rather than an anonymous row.
We would rather write that sentence than have you find it in a network log.
4The results of actions
A local outbox drains to the server: what was attempted, on which account, whether it succeeded. Idempotent, so a retry cannot double-count. This is what account analytics are built from.
5The connection graph
Computed on our servers, not on your machine. It is the exception that makes "all data stays local" untrue, and it is a deliberate trade: the graph work is heavy and it is what makes second-degree paths and warm-introduction routes possible at all.
6The managed AI — Pro only
On Pro, the text Booost is asked to write goes to our AI service, which routes it to the model provider. On Basic it goes to your provider on your key — and if that provider is Ollama, it goes nowhere at all: the model runs on your own machine and the prompt never leaves it.
That is the most under-sold thing on this site. If you want an AI writing assistant where no text ever leaves your computer, Basic with Ollama is that, and it costs less than Pro.
The switches
- Diagnostics are off by default. The selector-health and error diagnostics upload is opt-in: it does not run unless you turn it on, and there is a separate opt-out that keeps it off. Nothing on this page changes if you never touch it.
- Server sync can be killed entirely with the
BOOOST_NO_SERVER_SYNCenvironment variable. Every outbound call goes through one choke point that honours it — presence, schedule, outcomes, all of it. ⚠️ Honest caveat: this is an environment variable, not a checkbox in Settings. It works, and it is not yet a setting a non-technical user can find. - Basic + Ollama removes the AI provider from the picture completely.
- Deleting the local database removes everything on your machine. What has already reached the server is covered by the retention terms below.
Retention, deletion and your rights
The mechanics live in the contract, not on a marketing page, so this section links rather than paraphrases:
- Privacy notice — every flow above, with its legal basis and retention period.
- Terms of service and EULA.
- Acceptable use policy — including the part that says LinkedIn's User Agreement §8.2 prohibits automation wherever it runs, ours included.
- Cookie policy for this website.
Automatic deletion at the end of the retention period runs in the desktop app. ⚠️ The server side of it is still being built — tracked as #126, and we would rather say so here than let you assume it is done.
Booost is operated by Alfercom S.r.l., an Italian company; the data controller and contact details are on the legal page.
What we do not do
- We do not sell your data. Not to data brokers, not to enrichment vendors, not to anyone.
- We do not train models on your content. Your drafts, your inbox and your contacts are not training data.
- We do not read your inbox. Conversations sync into your local database and stay there.
- We do not have a "view as customer" mode that lets support see your screen or your data.
Questions this page gets asked
Do you have SOC 2 or ISO 27001? No. We are a small Italian company at launch, and claiming a certification we do not hold would be the fastest way to lose the argument this whole page is making.
Where are the servers? In the EU. The managed AI runs on Scaleway, in France.
Can I use Booost with no server connection at all? Almost. Licence validation needs to reach us; BOOOST_NO_SERVER_SYNC stops everything else. The app's actual work — campaigns, content, inbox — runs locally either way.
Is the extension different? Yes. Booost Personal works inside your own logged-in browser, never handles credentials, and takes no action on LinkedIn at all — it writes text into a box and you press publish.
What happens to my data if I stop paying? It is on your disk. The subscription gates what the app does, not access to the file.