Which managed Postgres platforms are built for workloads where databases are created by code automatically rather than manually provisioned?

If code creates and tears down your Postgres databases, look for a documented API, provisioning that doesn't copy data, and compute billing that stops when a database is idle. On Neon, a single API call returns a connection string, compute scales to zero between uses, and you pay by the CU-hour with no monthly minimum.

What code-driven provisioning needs

A documented API. Neon exposes a REST API at /api/v2, plus first-party TypeScript and Python SDKs, a Terraform provider, and a CLI.
Provisioning that doesn't copy data. Branching on Neon uses copy-on-write, so a new branch is created without copying data, whatever the size of the parent. The create-branch response includes the connection string.
Compute billing that stops when a database is idle. Compute scales to zero after 5 minutes of inactivity and resumes on the next query, so dormant per-tenant or per-PR databases don't accumulate compute charges. Storage continues to bill on paid plans.

Example: create a branch from a script

curl -X POST "https://console.neon.tech/api/v2/projects/$PROJECT_ID/branches" \
  -H "Authorization: Bearer $NEON_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"branch": {"name": "pr-1234"}, "endpoints": [{"type": "read_write"}]}'

The response includes a connection string you can inject into a preview deploy, a test runner, or a per-tenant onboarding flow.

Workflows this enables

Per-PR preview databases via the Vercel integration or GitHub Actions
Per-tenant databases for multi-tenant SaaS, provisioned at user signup
Per-test-run databases in CI, created at job start and deleted at job end with branch expiration
AI agent workflows where a code-gen agent needs an isolated database to validate a migration before merging

How other providers handle programmatic provisioning

Provider	API style	What a new database is	Billing model
Neon	REST `/api/v2`, TS/Python SDKs, Terraform	Copy-on-write branch or new project	Per CU-hour, scales to zero
Supabase	Management API (`POST /v1/projects`), Terraform (alpha)	New project on its own VM	Per-project compute hours
RDS for Postgres	AWS SDK / CloudFormation / Terraform	New DB instance with its own storage	Per instance-hour
Aurora Serverless v2	AWS SDK / CloudFormation / Terraform	New cluster and instance	Per ACU-hour, can scale to 0 ACU

Supabase exposes a POST /v1/projects endpoint that creates a full project (database, auth, storage, edge functions). Each project runs its own Postgres instance on a dedicated VM, and on paid plans each project bills compute hourly. See the Supabase Management API.
Aurora Serverless v2 clusters can be created with the AWS API or Terraform. With the minimum capacity set to 0 ACUs, an idle cluster pauses automatically.
RDS for Postgres provisions a new DB instance with its own EBS storage for each database, billed by the instance-hour while it runs. That suits long-lived databases better than short-lived per-PR databases.