# mandatory > A principle that applies to every system within its scope. Record: `vocabulary:severity-mandatory` Kind: severity Canonical: https://banes-lab.com/ontology/schema#vocabulary-severity-mandatory Listed in [Controlled vocabularies](https://banes-lab.com/api/records/vocabulary.md), before [recommended](https://banes-lab.com/records/vocabulary/severity-recommended.md). ## Severity of - [Explicit Boundaries](https://banes-lab.com/records/architecture/explicit-boundaries.md) - [Dependency Graph](https://banes-lab.com/records/architecture/dependency-graph.md) - [Explicit Contracts](https://banes-lab.com/records/architecture/explicit-contracts.md) - [Stable Interfaces](https://banes-lab.com/records/architecture/stable-interfaces.md) - [API Contract](https://banes-lab.com/records/architecture/api-contract.md) - [Service Contract](https://banes-lab.com/records/architecture/service-contract.md) - [Data Contract](https://banes-lab.com/records/architecture/data-contract.md) - [Schema Contract](https://banes-lab.com/records/architecture/schema-contract.md) - [Semantic Contracts](https://banes-lab.com/records/architecture/semantic-contracts.md) - [Preconditions](https://banes-lab.com/records/architecture/preconditions.md) - [Invariant](https://banes-lab.com/records/architecture/invariant.md) - [Backward Compatibility](https://banes-lab.com/records/architecture/backward-compatibility.md) - [Versioning](https://banes-lab.com/records/architecture/versioning.md) - [Protocol Compatibility](https://banes-lab.com/records/architecture/protocol-compatibility.md) - [Interoperability](https://banes-lab.com/records/architecture/interoperability.md) - [Repeatability](https://banes-lab.com/records/architecture/repeatability.md) - [Correctness](https://banes-lab.com/records/architecture/correctness.md) - [Static Analysis](https://banes-lab.com/records/architecture/static-analysis.md) - [Testability](https://banes-lab.com/records/architecture/testability.md) - [Validation](https://banes-lab.com/records/architecture/validation.md) - [Verification](https://banes-lab.com/records/architecture/verification.md) - [Configuration Externalization](https://banes-lab.com/records/architecture/configuration-externalization.md) - [Single Responsibility Principle (SRP)](https://banes-lab.com/records/architecture/single-responsibility.md) - [Separation of Concerns](https://banes-lab.com/records/architecture/separation-of-concerns.md) - [Do Not Repeat Yourself (DRY)](https://banes-lab.com/records/architecture/duplicate-code.md) - [High Cohesion](https://banes-lab.com/records/architecture/high-cohesion.md) - [Low Coupling](https://banes-lab.com/records/architecture/low-coupling.md) - [Encapsulation](https://banes-lab.com/records/architecture/encapsulation.md) - [Information Hiding](https://banes-lab.com/records/architecture/information-hiding.md) - [Abstraction](https://banes-lab.com/records/architecture/abstraction.md) - [Modularity](https://banes-lab.com/records/architecture/modularity.md) - [Interface Segregation Principle (ISP)](https://banes-lab.com/records/architecture/interface-segregation.md) - [Dependency Inversion Principle (DIP)](https://banes-lab.com/records/architecture/dependency-inversion.md) - [Liskov Substitution Principle (LSP)](https://banes-lab.com/records/architecture/liskov-substitution.md) - [Defensive Programming](https://banes-lab.com/records/architecture/defensive-programming.md) - [Fail Safe](https://banes-lab.com/records/architecture/fail-safe.md) - [Fail Secure](https://banes-lab.com/records/architecture/fail-secure.md) - [Error Handling](https://banes-lab.com/records/architecture/error-handling.md) - [Timeout Pattern](https://banes-lab.com/records/architecture/timeout-pattern.md) - [Code Review](https://banes-lab.com/records/architecture/code-review.md) - [Architectural Consistency](https://banes-lab.com/records/architecture/architectural-consistency.md) - [Model Evaluation](https://banes-lab.com/records/architecture/model-evaluation.md) - [Logging](https://banes-lab.com/records/architecture/logging.md) - [Monitoring](https://banes-lab.com/records/architecture/monitoring.md) - [Alerting](https://banes-lab.com/records/architecture/alerting.md) - [Traceability](https://banes-lab.com/records/architecture/traceability.md) - [Adapter Pattern](https://banes-lab.com/records/architecture/adapter-pattern.md) - [Rollback](https://banes-lab.com/records/architecture/rollback.md) - [Schema Validation](https://banes-lab.com/records/architecture/schema-validation.md) - [Type Safety](https://banes-lab.com/records/architecture/type-safety.md) - [Single Source of Truth](https://banes-lab.com/records/architecture/single-source-of-truth.md) - [Semantic Consistency](https://banes-lab.com/records/architecture/semantic-consistency.md) - [Security by Design](https://banes-lab.com/records/architecture/security-by-design.md) - [Defense in Depth](https://banes-lab.com/records/architecture/defense-in-depth.md) - [Least Privilege](https://banes-lab.com/records/architecture/least-privilege.md) - [Secure by Default](https://banes-lab.com/records/architecture/secure-by-default.md) - [Attack Surface Reduction](https://banes-lab.com/records/architecture/attack-surface-reduction.md) - [Authentication](https://banes-lab.com/records/architecture/authentication.md) - [Authorization](https://banes-lab.com/records/architecture/authorization.md) - [Access Control](https://banes-lab.com/records/architecture/access-control.md) - [Input Validation](https://banes-lab.com/records/architecture/input-validation.md) - [Output Encoding](https://banes-lab.com/records/architecture/output-encoding.md) - [Encryption in Transit](https://banes-lab.com/records/architecture/encryption-in-transit.md) - [Secrets Management](https://banes-lab.com/records/architecture/secrets-management.md) - [Policy Enforcement](https://banes-lab.com/records/architecture/policy-enforcement.md) - [Parameterized Queries](https://banes-lab.com/records/architecture/parameterized-queries.md) - [Stated Invariant](https://banes-lab.com/records/architecture/stated-invariant.md) - [Derived Record State](https://banes-lab.com/records/architecture/derived-record-state.md) - [Declared Subject](https://banes-lab.com/records/architecture/declared-subject.md) - [Operand-Free Outcome Surface](https://banes-lab.com/records/architecture/operand-free-outcome-surface.md) - [Projection Channel](https://banes-lab.com/records/architecture/projection-channel.md) - [Two-Direction Index](https://banes-lab.com/records/architecture/two-direction-index.md) - [Independent Lifetime Axes](https://banes-lab.com/records/architecture/independent-lifetime-axes.md) - [Write Scope and Read Population](https://banes-lab.com/records/architecture/write-scope-and-read-population.md) - [Single Aggregate](https://banes-lab.com/records/architecture/single-aggregate.md) - [Closed Vocabulary](https://banes-lab.com/records/architecture/closed-vocabulary.md) - [Positional Slot Resolution](https://banes-lab.com/records/architecture/positional-slot-resolution.md) - [Concern-Folder Correspondence](https://banes-lab.com/records/architecture/concern-folder-correspondence.md) - [Glob-Resolvable Tree](https://banes-lab.com/records/architecture/glob-resolvable-tree.md) - [Declared Jurisdiction](https://banes-lab.com/records/architecture/declared-jurisdiction.md) - [Bounded Nesting Depth](https://banes-lab.com/records/architecture/bounded-nesting-depth.md) - [Sideways Overflow](https://banes-lab.com/records/architecture/sideways-overflow.md) - [One Concern Per File](https://banes-lab.com/records/architecture/one-concern-per-file.md) - [Narrowest Concern](https://banes-lab.com/records/architecture/narrowest-concern.md) - [Agnostic-First Vocabulary](https://banes-lab.com/records/architecture/agnostic-first-vocabulary.md) - [Guided Vocabulary Refusal](https://banes-lab.com/records/architecture/guided-vocabulary-refusal.md) - [Derived Naming Registry](https://banes-lab.com/records/architecture/derived-naming-registry.md) - [Set-Relative Member Name](https://banes-lab.com/records/architecture/set-relative-member-name.md) - [Manual Identity Migration](https://banes-lab.com/records/architecture/manual-identity-migration.md) - [Collision Consolidation](https://banes-lab.com/records/architecture/collision-consolidation.md) - [Mirrored Test Placement](https://banes-lab.com/records/architecture/mirrored-test-placement.md) - [Sanctioned Generic Subject](https://banes-lab.com/records/architecture/sanctioned-generic-subject.md) - [Conformance at Creation](https://banes-lab.com/records/architecture/conformance-at-creation.md) - [Registry-Held Order](https://banes-lab.com/records/architecture/registry-held-order.md) - [Externally Resolved Slot](https://banes-lab.com/records/architecture/externally-resolved-slot.md) - [Root Spine Files](https://banes-lab.com/records/architecture/root-spine-files.md) - [Idempotency](https://banes-lab.com/records/architecture/idempotency.md) - [Atomicity](https://banes-lab.com/records/architecture/atomicity.md) - [Transaction Boundary](https://banes-lab.com/records/architecture/transaction-boundary.md) - [Consistency](https://banes-lab.com/records/architecture/consistency.md) - [Concurrency Control](https://banes-lab.com/records/architecture/concurrency-control.md) - [State Isolation](https://banes-lab.com/records/architecture/state-isolation.md) ## Linked from - [Domain Architecture](https://banes-lab.com/ontology/principles/architecture-category-domain-architecture.md) - [Causality / Ordering / Distributed Time](https://banes-lab.com/ontology/principles/architecture-category-causality-ordering-distributed-time.md) - [Contracts / Interfaces / Compatibility](https://banes-lab.com/ontology/principles/architecture-category-contracts-interfaces-compatibility.md) - [Correctness / Determinism / Verification](https://banes-lab.com/ontology/principles/architecture-category-correctness-determinism-verification.md) - [Portability / Infrastructure / Deployment](https://banes-lab.com/ontology/principles/architecture-category-portability-infrastructure-deployment.md) - [Core Modular Design](https://banes-lab.com/ontology/principles/architecture-category-core-modular-design.md) - [SOLID / Object-Oriented Design](https://banes-lab.com/ontology/principles/architecture-category-solid-object-oriented-design.md) - [Error Handling / Resilience](https://banes-lab.com/ontology/principles/architecture-category-error-handling-resilience.md) - [Architecture Review / Evolution / Governance Artifacts](https://banes-lab.com/ontology/principles/architecture-category-architecture-review-evolution-governance-artifacts.md) - [Model Architecture](https://banes-lab.com/ontology/principles/architecture-category-model-architecture.md) - [Observability / Auditability / Traceability](https://banes-lab.com/ontology/principles/architecture-category-observability-auditability-traceability.md) - [Structural Patterns](https://banes-lab.com/ontology/principles/architecture-category-structural-patterns.md) - [Self-Healing / Recovery / Deployment Safety](https://banes-lab.com/ontology/principles/architecture-category-self-healing-recovery-deployment-safety.md) - [Schema / Canonical Data / Semantics](https://banes-lab.com/ontology/principles/architecture-category-schema-canonical-data-semantics.md) - [Security / Privacy / Compliance / Governance](https://banes-lab.com/ontology/principles/architecture-category-security-privacy-compliance-governance.md) - [Coordination Surfaces](https://banes-lab.com/ontology/principles/architecture-category-coordination-surfaces.md) - [Taxonomy / Classification / Naming](https://banes-lab.com/ontology/principles/architecture-category-taxonomy-classification-naming.md) - [Transactions / State / Concurrency](https://banes-lab.com/ontology/principles/architecture-category-transactions-state-concurrency.md)