Render it and post it
in the same call.
BuildOnce publishes what it renders. Connect LinkedIn, Instagram, Facebook, Threads, X, TikTok, YouTube, Pinterest, Discord or Bluesky once, then post a design now or schedule it — from the dashboard, from the Render API with a publish block, or from an AI agent over MCP.
Who uses Social publishing
Social and content teams
One template becomes the week’s posts across every network, each scheduled from one place.
Products that post for users
Render a personalised image and post it to the accounts your workspace connected, in one request.
Agent workflows
An AI agent designs, renders and schedules the post in the same conversation.
Three steps
- 01
Connect accounts
Sign in to each platform from Social in the dashboard. Bluesky takes a handle and an app password instead.
- 02
Render with a publish block
List the account ids, the post text and, if you like, a time. Every account is checked before anything is drawn.
- 03
Follow the posts
GET /v1/social/posts shows each post’s status and link; scheduled posts can be edited or canceled until they go out.
Render and schedule in one request
One post per account, its media the rendered files — an allPages render becomes a carousel. A mistake for any account is a 400 that lists every problem, and nothing is charged.
curl -X POST https://buildonce.app/v1/templates/tpl_123/render \
-H "Authorization: Bearer fl_live_YOUR_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"format": "png",
"modifications": { "headline": "New post is live!" },
"publish": {
"accountIds": ["sac_li1", "sac_x9"],
"content": "Check out our latest design!",
"scheduledAt": "2026-10-25T09:00:00+05:00"
}
}'What Social publishing does
Ten platforms
LinkedIn, Instagram, Facebook, Threads, X, TikTok, YouTube, Pinterest, Discord and Bluesky, each through its own sign-in.
Video posts
MP4 renders post to Facebook, LinkedIn, TikTok and YouTube, and to Instagram as a reel or story.
Scheduling
Pick any future time and edit or cancel the post until it goes out; a video still rendering then is posted as soon as it is done.
Errors you can act on
A failed post says what went wrong and how to fix it, and can be retried once the account is reconnected.
What to know before you build
- Connected social accounts included: Launch 3, Grow 10 and Scale 25. Not available on Free.
- Extra accounts are $5 a month each ($50 a year on annual plans).
- Posts to X have a fair-use allowance per billing period.
- Each platform’s own rules apply: Instagram takes JPEG, TikTok and YouTube take video, and every network has its own text limit.
- Post analytics are available for YouTube, Pinterest and Bluesky today.
Go deeper
Social publishing questions
Short answers to what people ask most. The documentation covers every endpoint, tool and limit.
LinkedIn, Instagram, Facebook, Threads, X, TikTok, YouTube, Pinterest, Discord and Bluesky. Facebook lets you pick a Page and Pinterest a board when you connect.
Yes. Add a publish block to a render request with the account ids, the text and scheduledAt (ISO 8601, in the future). Leave out scheduledAt to post at once.
Yes: an MP4 render posts to Facebook, LinkedIn, TikTok and YouTube, and to Instagram as a reel or story. A video post carries one video and no images. The other platforms take images for now.
It depends on the plan, starting on Launch, and you can add extra accounts for $5 a month each. The pricing page lists each plan’s allowance.
The post shows as failed with an error that explains the cause, such as an account that needs reconnecting. Fix it and retry from the dashboard, the API or MCP.