Sandloom

Python backend framework for AI-driven development.

Build with people and AI agents while the framework enforces module boundaries, owns transactions and provides shared mechanisms for authorization, tenancy, event delivery and idempotency.

Why Sandloom

• AI-driven development: a consistent module structure, typed contracts, CLI scaffolding, agent instructions and executable quality gates keep changes scoped as the application grows.
• Enforced module boundaries: business modules communicate through typed events and contracts. Architecture checks reject cross-module imports.
• Pluggable infrastructure: application modules use capability contracts instead of raw backend clients. Configure compatible registered drivers or implement adapters without spreading infrastructure SDKs through business code. PostgreSQL and Redis are the documented production backends.
• Monolith to services: deploy the same business modules together or in separate services using module selection and service bindings. Moving existing data to a module's own database is a separate offline extraction step.
• Built-in mechanisms: transaction ownership, one writer per request, authorization rechecks before commit, tenant isolation, a transactional outbox, durable consumers and idempotent commands.

Install and create an application

Requires Python 3.11+, uv and Docker for local PostgreSQL and Redis services. Sandloom is an alpha; --pre allows pip to select its prerelease packages.

python -m pip install --pre "sandloom[standard]"
sandloom new myapp --with identity,tenancy,billing --module notes

Follow the printed next steps to install application dependencies, start local services, run checks and migrations, and launch the API.

The standard extra includes Redis, Celery and the separate sandloom-identity, sandloom-tenancy and sandloom-billing packages. Install sandloom alone for the kernel, public sandloom.sdk, shared contracts, CLI and composition root. Other extras: redis, celery, fast, check, testing and sentry.

Inspect before editing

From the application root, after installing its dependencies:

uv run sandloom generate
uv run sandloom graph
uv run sandloom context notes
uv run sandloom explore

graph shows module purposes and declared connections; context gives a compact map of one module's contracts, events and owned files. Both default to text; request JSON explicitly with --format json. explore opens an offline browser view with declared processes, interface impact and architecture comparisons. See module maps and the architecture explorer.

Alpha status

Sandloom is under active development. Review the compatibility policy and release notes before upgrading; a minor version in the 0.x series may introduce breaking changes. The framework's documented guarantees have specific scopes; consult the guarantee reference for their mechanisms and limits.

Links

• Source and issue tracker
• Documentation
• Examples
• Compatibility policy

License

Apache-2.0. Copyright 2026 Vasyl Cherniavskyi. See LICENSE and NOTICE.