The Showly alternative that stays private after you publish.

What Showly is

Showly describes itself as website hosting for AI-created sites. An agent connects over MCP, stages edits into a Showly workspace, builds a private preview, and a person promotes that preview to production. The docs list nineteen tools across read, plan, build, ship and inspect groups, including create_preview, request_publish, publish_site and rollback_to_version. It is a deployment pipeline with a review gate, aimed at agents, and it is a good one.

It is run by Cubo World Inc., registered in Lewes, Delaware. Pricing is credit-metered: Free gives 300 credits a month, Pro 3,000 at $12 a month or $10 billed yearly, Enterprise is by contract and adds single sign-on across an organisation, deployment into your own cloud, and publish approval workflows.

Where the two products actually differ

Both let an agent publish. The difference is what happens to the page after that, and it is a bigger difference than the feature lists suggest.

Showly’s privacy model is pre-publication. A preview is private by default, carries a short sharing code or a password you set between 6 and 128 characters, is served with a noindex header, and on Pro can be restricted to signed-in members of the workspace. That is a careful review surface. Once the preview is promoted, it becomes a live site reachable by anyone holding the URL, which is the right default when the output is a marketing page or a demo.

Stacktree’s privacy model is post-publication, because the published page is the deliverable. Every page starts on an unguessable link that acts as the credential. Any plan can add a shared passcode, and from Solo a page can be restricted to one client’s email domain with magic-link verification. Nothing is listed and nothing is indexed. There is no separate preview stage, because there is nothing to promote the page into.

Where Showly is the better choice

Three cases, and they are real rather than polite.

• You want a human approval step in the pipeline. Showly is built around it: the agent stages, a person ships. Stacktree has no approval workflow. An agent with a connection publishes, and the control you have is the gate on the page and the ability to replace or delete it.
• The output is meant to be public. If the end state is a site anyone should be able to open, Showly’s defaults match your job and its credit model is cheap. Entry price is $12 a month against our $19, and its free plan is a monthly credit allowance rather than a three-page lifetime cap.
• You need several hostnames on one site. Showly allows up to five custom hostnames per live site on every plan, including Free. Stacktree starts custom domains at Solo, with one on Solo, ten on Studio and twenty-five on Firm.

Where Stacktree wins

• The gate is on the live page. Passcode on every plan, including the free one and anonymous publishes. Email-domain gate with magic-link verification from Solo. You can also read a passcode back when a client loses it.
• A client layer, not a site list. A client space gives one client a permanent address on your domain, a portal at the root listing every deliverable newest first, and a gate set once on the space that every page filed under it inherits, including the one you publish next month. The client never makes an account.
• You can tell whether it was read. From Solo: opens, unique viewers, and when the page was last opened. From Studio: aggregate time on page, scroll depth and an attention heatmap. Separate labelled share links per recipient carry their own expiry, use limit and revoke, so you can tell which link was used. Showly puts visitor analytics on Pro and above.
• The page answers questions. Ask this page puts a question box on a deliverable. Answers come from that page only, cite the passage they used and light it up, and a question the page cannot answer comes back to you as the brief for the next version. On every plan, off by default.
• A Markdown twin of every page. Send Accept: text/markdown to a page address, or add /_page.md, and you get the page with headings, lists, tables and links intact. Your client’s agent can read the proposal you sent, not only your client. Gates apply to the Markdown exactly as they do to the HTML.
• Where the agent already lives. MCP over OAuth for Claude Code, Codex, Cursor, OpenCode and Amp with one npx stacktree-install, a Claude.ai connector, a Slack app, and an anonymous HTTP publish that needs no key at all, which is how browser-and-VM assistants such as Meta Muse reach it today.

Version history exists on both

Worth being precise, because it is the row people assume we lose. Showly keeps site versions with list_site_versions and diff_site_versions, and rollback swaps the route pointer back. Stacktree shipped the same shape on 17 September 2026: every update keeps the version it replaced, the page screen has a Versions section, and agents get list_versions and restore_version over MCP. Free keeps the last five, paid plans the last fifty. A restore is itself an update, so the copy you restored over is kept too.

Pricing, side by side

Showly meters credits. Stacktree charges one flat price per workspace and never per seat. Showly’s free plan gives 300 credits a month with unlimited sites and previews that never expire. Ours gives three pages in total, 25 MB each, live for seven days, on unguessable links with a small Made with Stacktree footer. Theirs is the more generous free plan for volume. Ours is a trial you can send to a real client before you pay.

Above that: Pro at $12 a month, or $10 billed yearly, with 3,000 credits, visitor analytics, permanent audit history and one seat included. Stacktree Solo is $19 for twenty-five pages that never expire, one custom domain, one client space, passcodes and email gates on all of them, viewer numbers, and no footer. Studio at $79 adds unlimited pages, ten domains, ten client spaces and engagement analytics. Full numbers on pricing.

Switching

• What transfers: the built HTML and your domains. Publish with publish_html, the dashboard, or a single unauthenticated curl -X POST https://api.stacktr.ee/sites -F file=@page.html, then point DNS at Stacktree from Solo up.
• What you gain: a gate on the live page, client spaces on your own domain, Ask this page, the Markdown twin, and flat pricing with no credit balance to watch.
• What you give up: the stage-then-approve workflow, the credit-metered free allowance, five hostnames per site on a free plan, and Showly’s build logs and deployment diagnostics.