Commercial Patterns

Production patterns that work with zero kernel changes.

Every pattern below runs on the stock kernel. No patches, no hooks, no monkey-patching. The reactive graph (Signal + @effect + @computed) handles propagation automatically.

Each pattern has a dedicated deep-dive page, a runnable example in src/signalpy/examples/, and tests in test_examples.py.

The Patterns

# Pattern What It Proves
0 Reactive Intent vs Default When @effect’s default semantics need an escape hatch — batch(), is_stale(), cancel_on_supersede, cross-thread writes
1 Secret Rotation Config Signal propagates through credential chain to consumer @effect
2 A/B Testing Map injection + @computed = runtime-adjustable routing
3 Multi-Tenant Isolation instantiate() + properties + structural scoping = L3 targeted
4 Extension Bundle hot_add + @subscribe + bus calls = plugin system
5 Circuit Breaker Components create their own Signals for local reactive state
6 Audit Trail @subscribe wildcards + set_policy = cross-cutting concerns
7 Unit Testing Minimal kernel + fakes = isolated tests with real reactivity
8 Hot Code Update snapshot → teardown → replace → activate → restore (kernel change)

The Thesis

These seven patterns span different domains — credential management, experimentation, multi-tenancy, plugin systems, resilience, compliance, and testing. They use different kernel features — @effect, @computed, @subscribe, hot_add, set_policy, instantiate(), map injection, target routing.

None of them required kernel changes. The kernel is 3 reactive primitives (Signal, Computed, Effect) + component wiring. The patterns are just components.

Running

PYTHONPATH=src python -m signalpy.examples.secret_rotation
PYTHONPATH=src python -m signalpy.examples.ab_testing
PYTHONPATH=src python -m signalpy.examples.multi_tenant
PYTHONPATH=src python -m signalpy.examples.extension_bundle
PYTHONPATH=src python -m signalpy.examples.circuit_breaker
PYTHONPATH=src python -m signalpy.examples.audit_trail

Tests

PYTHONPATH=src python -m pytest src/signalpy/tests/test_examples.py -v