pyscoped 0.1.2

Universal object-isolation and tenancy-scoping framework

Scoped

Universal object-isolation and tenancy framework for Python.

Scoped guarantees that anything built on it can be isolated, shared, traced, and rolled back — to any degree, at any time, by anyone with the right to do so.

Zero dependencies. SQLite included. 1,500+ tests. Python 3.11+.

pip install pyscoped

Why Scoped

Most frameworks give you a database and leave isolation, sharing, auditing, and rollback as your problem. Scoped makes them structural guarantees:

• Every object is creator-private by default. Sharing requires explicit projection into a scope.
• Every mutation creates a new version. No in-place updates. Full history preserved.
• Every action is hash-chained. Tamper-evident audit trail with before/after state.
• Everything is rollbackable. Any action can be reversed to any point in time.
• Deny always wins. When rules conflict, DENY overrides ALLOW. No exceptions.

This makes Scoped the base layer for multi-tenant applications, clinical systems, financial platforms, compliance-sensitive workflows, and AI agent orchestration.

Quick Start

from scoped.storage.sqlite import SQLiteBackend
from scoped.identity.principal import PrincipalStore
from scoped.objects.manager import ScopedManager
from scoped.tenancy.lifecycle import ScopeLifecycle
from scoped.tenancy.projection import ProjectionManager
from scoped.audit.writer import AuditWriter

# 1. Initialize storage (SQLite, zero config)
backend = SQLiteBackend("app.db")
backend.initialize()

# 2. Create services
principals = PrincipalStore(backend)
audit = AuditWriter(backend)
manager = ScopedManager(backend, audit_writer=audit)
scopes = ScopeLifecycle(backend, audit_writer=audit)
projections = ProjectionManager(backend, audit_writer=audit)

# 3. Create a principal (the acting user)
alice = principals.create_principal(kind="user", display_name="Alice")
bob = principals.create_principal(kind="user", display_name="Bob")

# 4. Create an object — it's creator-private
obj, v1 = manager.create(
    object_type="document",
    owner_id=alice.id,
    data={"title": "Q4 Report", "status": "draft"},
)

# Alice can read it
assert manager.get(obj.id, principal_id=alice.id) is not None

# Bob cannot
assert manager.get(obj.id, principal_id=bob.id) is None

# 5. Update creates a new immutable version
obj, v2 = manager.update(
    obj.id,
    principal_id=alice.id,
    data={"title": "Q4 Report", "status": "final"},
    change_reason="Finalized for review",
)
assert obj.current_version == 2  # v1 is preserved, untouched

# 6. Share via scope projection
team = scopes.create_scope(name="Finance Team", owner_id=alice.id)
from scoped.tenancy.models import ScopeRole
scopes.add_member(team.id, principal_id=bob.id, role=ScopeRole.VIEWER, granted_by=alice.id)
projections.project(scope_id=team.id, object_id=obj.id, projected_by=alice.id)

# Now Bob can see it
assert manager.get(obj.id, principal_id=bob.id) is None  # manager is owner-only
# But visibility engine shows it
from scoped.tenancy.engine import VisibilityEngine
vis = VisibilityEngine(backend)
assert obj.id in vis.visible_object_ids(bob.id)

# 7. Every action was traced with hash-chained audit
from scoped.audit.query import AuditQuery
trail = AuditQuery(backend).for_target("document", obj.id)
assert len(trail) >= 2  # CREATE + UPDATE, each with before/after state

Architecture

16 composable layers. Each depends only on layers below it.

Layer 0   Compliance    Validates all invariants across layers
Layer 1   Registry      Universal construct registration (URNs)
Layer 2   Identity      Generic principal machinery + ScopedContext
Layer 3   Objects       Versioned, isolated data objects
Layer 4   Tenancy       Scopes, membership, projection (sharing)
Layer 5   Rules         Deny-overrides policy engine
Layer 6   Audit         Hash-chained, immutable, append-only trace
Layer 7   Temporal      Point-in-time reconstruction + rollback
Layer 8   Environments  Ephemeral workspaces
Layer 9   Flow          Stages, pipelines, promotions
Layer 10  Deployments   Graduation to external targets with gates
Layer 11  Secrets       Encrypted vault with zero-trust access
Layer 12  Integrations  Sandboxed plugins, hooks, external systems
Layer 13  Connector     Cross-org meshing, federation, marketplace
Layer 14  Events        Asynchronous scoped event bus + webhooks
Layer 15  Notifications Principal-targeted messages
Layer 16  Scheduling    Recurring schedules, scoped job execution

9 extensions enrich existing layers: Migrations (A1), Contracts (A2), Rule Extensions (A3), Blobs (A4), Config Hierarchy (A5), Search (A6), Templates (A7), Tiering (A8), Import/Export (A9).

The 10 Invariants

These are absolute. The compliance engine (Layer 0) validates them.

1. Nothing exists without registration. Every construct has a URN in the registry.
2. Nothing happens without identity. Every operation requires an acting principal.
3. Nothing is shared by default. Objects start creator-private. Sharing is explicit.
4. Nothing happens without a trace. Every action produces a hash-chained audit entry.
5. Nothing is truly deleted. Objects are tombstoned. Versions retained. Audit is append-only.
6. Deny always wins. DENY overrides ALLOW when rules conflict.
7. Revocation is immediate. Same-transaction enforcement.
8. Everything is versioned. Every mutation creates a new immutable version.
9. Everything is rollbackable. Any action can be reversed to any point in time.
10. Secrets never leak. Values never appear in audit, snapshots, or connector traffic.

Core API

Objects (Layer 3)

from scoped.objects.manager import ScopedManager

manager = ScopedManager(backend, audit_writer=audit)

# Create — returns (ScopedObject, ObjectVersion)
obj, ver = manager.create(object_type="task", owner_id=user.id, data={"title": "Ship it"})

# Read — returns None if principal cannot access
obj = manager.get(obj.id, principal_id=user.id)

# Update — creates new version, never modifies old
obj, ver = manager.update(obj.id, principal_id=user.id, data={"title": "Ship it", "done": True})

# Soft delete — tombstones, never physically deletes
tombstone = manager.tombstone(obj.id, principal_id=user.id, reason="Obsolete")

Tenancy (Layer 4)

from scoped.tenancy.lifecycle import ScopeLifecycle
from scoped.tenancy.projection import ProjectionManager
from scoped.tenancy.models import ScopeRole, AccessLevel

scopes = ScopeLifecycle(backend, audit_writer=audit)
projections = ProjectionManager(backend, audit_writer=audit)

# Create scope (owner auto-added as OWNER member)
scope = scopes.create_scope(name="Team Alpha", owner_id=alice.id)

# Add members
scopes.add_member(scope.id, principal_id=bob.id, role=ScopeRole.EDITOR, granted_by=alice.id)

# Project an object into the scope (sharing it with members)
projections.project(scope_id=scope.id, object_id=obj.id, projected_by=alice.id)

# Revoke sharing
projections.revoke_projection(scope_id=scope.id, object_id=obj.id, revoked_by=alice.id)

Rules (Layer 5)

from scoped.rules.engine import RuleStore, RuleEngine
from scoped.rules.models import RuleType, RuleEffect, BindingTargetType

store = RuleStore(backend)
rule = store.create_rule(
    name="deny-external-access",
    rule_type=RuleType.ACCESS,
    effect=RuleEffect.DENY,
    priority=10,
    created_by=admin.id,
)
store.bind_rule(rule.id, target_type=BindingTargetType.SCOPE, target_id=scope.id, bound_by=admin.id)

engine = RuleEngine(backend)
result = engine.evaluate(action="read", principal_id=user.id, scope_id=scope.id)
# result.allowed, result.deny_rules, result.allow_rules

Audit (Layer 6)

from scoped.audit.writer import AuditWriter
from scoped.audit.query import AuditQuery

writer = AuditWriter(backend)
entry = writer.record(
    actor_id=user.id,
    action=ActionType.CREATE,
    target_type="document",
    target_id=obj.id,
    after_state={"title": "Draft"},
)
# entry.hash — SHA-256 hash linking to previous entry
# entry.previous_hash — hash of the entry before this one
# entry.sequence — monotonically increasing sequence number

query = AuditQuery(backend)
trail = query.for_target("document", obj.id)  # full history
trail = query.for_actor(user.id)               # everything a user did

Temporal (Layer 7)

from scoped.temporal.rollback import RollbackExecutor
from scoped.temporal.reconstruction import StateReconstructor

# Roll back a single action
executor = RollbackExecutor(backend, audit_writer=audit)
result = executor.rollback_action(trace_id, actor_id=admin.id, reason="Mistake")

# Roll back to a point in time
result = executor.rollback_to_timestamp("document", doc.id, at=yesterday, actor_id=admin.id)

# Cascading rollback (action + all dependent actions)
result = executor.rollback_cascade(trace_id, actor_id=admin.id)

# Reconstruct state at a past timestamp
reconstructor = StateReconstructor(backend)
state = reconstructor.at_timestamp("document", doc.id, timestamp)

Framework Adapters

Install with extras for your framework:

pip install pyscoped[django]    # Django ORM backend + middleware
pip install pyscoped[fastapi]   # FastAPI middleware + Pydantic schemas
pip install pyscoped[flask]     # Flask extension + admin blueprint
pip install pyscoped[mcp]       # MCP server for AI agents

Django

# settings.py
INSTALLED_APPS = ["scoped.contrib.django"]
MIDDLEWARE = ["scoped.contrib.django.middleware.ScopedContextMiddleware"]

# Uses the Django database connection as the storage backend.
# Management commands: scoped_health, scoped_audit, scoped_compliance

FastAPI

from fastapi import FastAPI
from scoped.contrib.fastapi.middleware import ScopedContextMiddleware
from scoped.contrib.fastapi.router import router as scoped_router

app = FastAPI()
app.add_middleware(ScopedContextMiddleware, backend=backend)
app.include_router(scoped_router)  # /scoped/health, /scoped/audit

Flask

from flask import Flask
from scoped.contrib.flask.extension import ScopedExtension

app = Flask(__name__)
scoped = ScopedExtension(app)  # auto-inits backend, injects g.scoped_context

MCP (Model Context Protocol)

from scoped.contrib.mcp.server import create_scoped_server

mcp = create_scoped_server(backend)
mcp.run()
# Tools: create_principal, create_object, get_object, create_scope, list_audit, health_check
# Resources: scoped://principals, scoped://health, scoped://audit/recent

Storage

The default backend is SQLite (zero dependencies, included). The StorageBackend interface can be implemented for any database:

from scoped.storage.sqlite import SQLiteBackend

# In-memory (tests, prototyping)
backend = SQLiteBackend(":memory:")
backend.initialize()

# File-based (production single-node)
backend = SQLiteBackend("app.db")
backend.initialize()

# Django ORM backend (production)
from scoped.contrib.django import get_backend
backend = get_backend()

Testing

Scoped includes a compliance testing engine for verifying invariants:

from scoped.testing.base import ScopedTestCase

class MyTest(ScopedTestCase):
    def test_isolation(self):
        obj = self.create_object("doc", self.user_a, {"title": "Private"})
        # user_b cannot read user_a's object
        assert self.read_object(obj.id, as_principal=self.user_b) is None

    def test_versioning(self):
        obj = self.create_object("doc", self.user_a, {"v": 1})
        self.manager.update(obj.id, principal_id=self.user_a.id, data={"v": 2})
        # Both versions exist
        versions = self.backend.fetch_all(
            "SELECT * FROM object_versions WHERE object_id = ?", (obj.id,)
        )
        assert len(versions) == 2

pip install pyscoped[dev]
pytest                          # 1,500+ tests
pytest tests/test_objects/      # one layer
pytest tests/test_compliance/   # invariant validation

Test Coverage

Component	Tests
Core Layers 1-13	820
Extensions A1-A9	386
Events, Notifications, Scheduling	117
Compliance Engine (Layer 0)	87
Framework Adapters (D1-D4)	83
Total	1,493+

Documentation

• Architecture Overview
• Getting Started Guide
• API Reference
• Framework Adapters
• Layer Documentation (Layers 0-16)
• Extension Documentation (A1-A9)
• Changelog

Requirements

• Python 3.11+
• No required dependencies (SQLite backend included)

License

MIT License. See LICENSE for details.