Polsia alternatives in 2026: twelve tools, by how much they do on their own and who keeps the code
By Tudor Bungardean. Published 23 September 2026. Every outside fact read on 23 September 2026.
The closest Polsia alternatives are Marblism and Durable for a business run for you, and Castan or CoFounder.AI for a founder who wants to approve the big moves and keep the code. Two kinds of product get compared with Polsia. The first builds or runs a company for you: it writes the site, runs the ads, answers the support inbox. The second remembers the company you already have: it reads your email, chats and meetings and answers questions about them, and some of them act on what they read. The tables below hold both kinds, with list prices as published on the day we read them, and two columns that decide more than the price does: how much the tool does without asking, and who keeps the code and the data.
Polsia alternatives that build or run a company
| Product | What it does | Price | Autonomy | Who keeps what |
|---|---|---|---|---|
| Polsia | Idea to running business, nightly AI CEO | $20 to $200 a month, plus 3% of payments and 20% of ad spend | Fully autonomous | Code downloadable as a copy, no git, domains in Polsia’s name for 60 days |
| Castan | Runs your company with you: memory over Gmail, Slack, calls, invoices and GitHub; agents that propose and act with approval; software and idea pages built into your repo; an interview after every sign-up; any MCP server | $29 to $599 a month per workspace, free tier | Approval first for anything that leaves the workspace; internal steps on auto | Code as pull requests in your repository; data stays in your accounts |
| CoFounder.AI | An agentic co-founder plus six specialists | $39 a month | Approval on the five biggest moves | Not stated on the pages we read |
| VenturOS | Seven AI executives in Slack, Gmail, Notion and Linear | $200 and $500 a month, announced | Drafts alone; publishing and spending wait | Not stated; invite-only beta since January 2026 |
| Marblism | Seven AI employees: inbox, socials, SEO, leads, calls | $24 to $44 a month for 50 agent hours | Mostly autonomous; email replies are drafts | Runs on Marblism |
| Durable | Site, CRM, blog and lead agents | Free to $49 a month | Automatic within caps | Runs on Durable |
| Thomas | A YC-backed AI founder that starts its own companies | Not for sale | Fully autonomous, a human signs | Not applicable |
Polsia alternatives for company memory
| Product | What it does | Price | Autonomy | Who keeps what |
|---|---|---|---|---|
| Supermemory Company Brain | Slack-native shared memory over Granola, Gmail, Notion, Linear, GitHub | $100 a month flat, no seat cap | Joins threads unprompted, no approval gate | Open-source core you can run |
| Dust | Agents over 20+ sources with tools | €24 to €150 a seat plus credits | Confirmation before modifying tools | Hosted; API access to your data |
| Granola | Notetaker turned company context | $14 to $35 a user | Read only | Hosted |
| Circleback | Notetaker with questions across meetings | Free with 30 days of history, then $15 a month | Read only | Hosted |
| Fyxer | Inbox, calendar and meeting assistant | $30 to $50 a user | Drafts only, never sends | Hosted |
| Onyx | Open-source search and agents over 40+ connectors | Free self-hosted, $20 a user hosted | Read only by default | Open source, self-hostable |
How to read the tables
- Autonomy is the column that decides whether you sleep. Fully autonomous tools send things under your name; drafts-only tools never do; approval-first tools do when you say so. Pick the level you can live with before you pick a price.
- Per-seat pricing punishes the team that connects everyone, and a memory product needs everyone connected. Flat prices per company exist at Supermemory, Marblism and Castan.
- Who keeps the code and the data matters the day you leave. Only Onyx and Supermemory ship a core you can run yourself; Castan writes code into your repository and leaves the data in your accounts; the builders keep the running system.
- Fees on your business are unusual. Of the twelve, only Polsia takes a share of your customers’ payments and your ad spend.
Castan wrote this list and is on it. Every price and claim carries the day it was read; if one is out of date, write to hello@castan.ai and it will be corrected with the date of the change.
Questions people ask
What is the closest alternative to Polsia?
For a business run for you without asking, Marblism and Durable are the closest in shape and price. For a founder who wants to keep control and the code, Castan and CoFounder.AI ask before the big moves.
Which alternatives have a free plan?
Castan, Durable, Circleback and self-hosted Onyx have free tiers as of 23 September 2026. Polsia has no free trial.
Which tools do not charge per seat?
Polsia, Castan, Supermemory Company Brain, Marblism and Durable price per company or account. Dust, Granola, Circleback, Fyxer and hosted Onyx price per user.
Which tools let me keep the code?
Castan writes code as pull requests into your own GitHub repository. Onyx and Supermemory are open source and can be self-hosted. Polsia allows a download of the code but no git access and no self-serve deploy.