Module Relation Repair

About this pattern

This is a generated FPF pattern page projected from the published FPF source. It is canonical FPF content for this ID; it is not a FPF Reference product feature page.

How to use this pattern

Read the ID, status, type, and normativity first. Use the content for exact wording, the relations for adjacent concepts, and citations to keep active work grounded without pasting the whole specification.

Type: Architectural pattern Status: Stable Normativity: Normative unless explicitly marked informative

Use this pattern when an architecture or engineering text says "module", "component", "interface", "port", "platform", or "open architecture", and the phrase is doing more than ordinary orientation. If a stratification or architecture-operation source label covered by C.30.STRAT is doing the work, apply C.30.STRAT first; use A.6.M only when that repair recovers a module-interface relation. Use A.6.M when the question under repair is whether one holon is being treated as a replaceable, reusable, or separately changed structural unit of a larger holon under a declared module-interface viewpoint.

Keywords

  • module relation
  • component
  • interface
  • port
  • platform
  • layer
  • stack
  • open architecture
  • substitutability
  • interface specification.

Relations

A.6.Mexplicit referenceRole Taxonomy
A.6.Mexplicit referenceReusable Structure Accounting
A.6.Mexplicit referenceMathematical Lens Use
A.6.Mexplicit referenceEpistemic Precision Restoration
A.6.Mexplicit referenceEvidence Graph Referring (C-4)
A.6.Mexplicit referenceDecision Theory (Decsn-CAL)
A.6.Mexplicit referenceContract Unpacking for Boundaries

Content

Problem frame

Use this pattern when an architecture or engineering text says "module", "component", "interface", "port", "platform", or "open architecture", and the phrase is doing more than ordinary orientation. If a stratification or architecture-operation source label covered by C.30.STRAT is doing the work, apply C.30.STRAT first; use A.6.M only when that repair recovers a module-interface relation. Use A.6.M when the question under repair is whether one holon is being treated as a replaceable, reusable, or separately changed structural unit of a larger holon under a declared module-interface viewpoint.

The first useful move is ModuleRelationRepairNote:

ModuleRelationRepairNote:
  wholeHolonRef:
  candidateModuleHolonRef:
  boundedContextRef:
  moduleInterfaceViewpointRef: VP.ModuleInterface
  boundaryRef:
  interfaceSpecificationRef or interfaceSpecificationGap:
  admissibilityConditions:
  substitutionOrChangePolicyRef:
  claimBoundary:
  notAModuleBecause:
  governedNonModuleClaimPatternRefs:
  stopCondition:

Ordinary use stops when the whole, candidate module, boundary, interface specification, admissibility conditions, substitution or change policy, blocked false interpretation, and neighboring work, procedural, role, or enactor governing pattern choice are clear enough to choose the next architecture move. Use the fuller moduleIn(...) relation record only when the claim being made involves substitutability, conformance, publication, evidence, assurance, change policy, repeated reuse, or cross-team coordination.

What goes wrong if A.6.M is missed: a functional link becomes a module interface; a signature becomes an implemented interface; a port label becomes proof of integration; "open" becomes a decoration; a platform label hides the actual extension rules; a stratification or architecture-operation source label bypasses [C.30.STRAT](/generated/patterns/C.30.STRAT) and mints a false local kind; autonomy-like wording is confused with separate module change policy; and a module diagram starts being used for claims governed elsewhere.

What A.6.M buys in practice: the practitioner can repair one module or interface phrase into a module-relation record, see which FPF pattern governs any remaining non-module claim, and stop before full measurement, evidence, or mechanism-suite records are needed.

Not this pattern when the question under repair is the general architecture claim, selected architecture structure kind, structural view, stratification wording or source-label recovery, function wording, procedural or work-package wording, role or enactor wording, autonomous operation, independent acting, unsupervised decision or action, measurement, modularity characterization, or reusable-structure residue. Use [C.30](/generated/patterns/C.30), [C.30.ASV](/generated/patterns/C.30.ASV), [C.30.STRAT](/generated/patterns/C.30.STRAT), [A.6.F](/generated/patterns/A.6.F), [A.15](/generated/patterns/A.15), [A.2](/generated/patterns/A.2), [E.16](/generated/patterns/E.16), [C.31](/generated/patterns/C.31), [C.16](/generated/patterns/C.16), or [C.31.RSA](/generated/patterns/C.31.RSA) as appropriate. For any other claim being made, apply the governing FPF pattern and keep A.6.M only for the module-relation and interface-specification portion.

E.10.ARCH relation. A.6.M is the precision-restoration pattern for module-interface relation wording, interface-specification wording, platform-grammar wording, substitutability wording, and open-architecture module-interface claims. [E.10](/generated/patterns/E.10), [E.10.ARCH](/generated/patterns/E.10.ARCH), or [C.30.STRAT](/generated/patterns/C.30.STRAT) applies A.6.M only after the recovered result is a module-interface relation, interface specification, platform grammar, substitution or change policy, or open-architecture module-interface claim. If the source wording is still a stratification or architecture-operation source label covered by [C.30.STRAT](/generated/patterns/C.30.STRAT), apply [C.30.STRAT](/generated/patterns/C.30.STRAT) first. If the claim being made is non-module work, role, evidence, assurance, gate, decision, characteristic, flow, autonomy, component, mechanism, or mathematical-lens use, apply the governing pattern named in [A.6.M:12](/generated/patterns/A.6.M#relations) and keep A.6.M only for the module-interface slice when that module-interface relation remains the claim being made.

Problem

Engineering teams use module language for several different things:

  • a component in a part-whole decomposition;
  • a replaceable unit under a declared interface;
  • a functional element;
  • a software package, neural-network block, hardware board, chiplet, subsystem, service, team boundary, or delivery unit;
  • a published API, protocol, signature, port, connector, or endpoint;
  • a platform extension point;
  • a control relation, deployment scope, or stratification or architecture-operation source label that still needs C.30.STRAT recovery;
  • an open-architecture claim.

These are useful ordinary words, but they do not establish the same FPF claim. A module claim is not created by a label. A conforming module-interface claim states how a candidate U.Holon relates to a larger U.Holon under VP.ModuleInterface: boundary, interface specification, admissibility conditions, substitution or change policy, and any evidence, conformance, or admissible-use expectation being claimed.

The practical question is: does this phrase name a module relation, a component relation, a functional allocation, a procedural or work-package relation, a role or enactor relation, a deployment or placement structure, an interface specification, a signature declaration, a port or endpoint slot, a TGA flow crossing, a mechanism realization, a platform grammar, a control relation, an autonomy-like operation claim, a source label governed first by C.30.STRAT, or only plain source wording?

Forces

ForceTension
Engineering convenience vs relation precisionPractitioners need short words such as module and interface, but claim-bearing use must recover relation kind, slots, boundary, and admissible use.
Module role vs root kindA module is often a holon in a module-interface role; minting U.Module would hide context, viewpoint, and relation conditions.
Interface label vs interface specificationAn API name, port label, connector label, or signature may substantiate an interface claim, but it is not by itself substitutability or conformance.
Function-flow-module proximity vs false identityFunctions, E.18 flow relations, control relations, mechanisms, and module interfaces often meet at the same artifact, but each has a different governing pattern.
Open architecture payoff vs open label overreadMOSA and open-system practice make open interfaces useful only with standards, conformance expectations, replacement or change policy, and data or access constraints when those conditions are part of the claim being made.
Team boundary vs module boundaryConway's law and mirroring practice make team communication boundaries and delivery-responsibility scopes architecture-relevant, but they do not turn a team boundary, delivery unit, or role/enactor arrangement into a module interface by identity.
Parallel decomposition vs serial bottleneckAmdahl-style reasoning makes serial work, synchronization, communication overhead, and shared resource limits visible; more modules, teams, or parallel paths do not automatically improve throughput or evolvability.
Cheap repair vs full evidence packMost cases need a relation repair note, not a full conformance, evidence, assurance, gate, or mechanism-suite record.

Solution

A.6.M specializes A.6.P for module, component, interface, platform, and open-architecture wording when the recovered result is a module-interface relation, interface specification, platform grammar, substitutability relation, or open-architecture module-interface claim. Stratification or architecture-operation source labels covered by C.30.STRAT are governed by C.30.STRAT until that repair recovers a module-interface relation; A.6.M applies only to that recovered module-interface result. A.6.M does not mint root kinds from those source labels.

A module is a U.Holon viewed in a declared bounded context as a replaceable, reusable, or separately changed structural unit of a larger U.Holon under VP.ModuleInterface, with explicit boundary, interface specification, admissibility conditions, and admissible substitution or change policy.

For modular synthesis, A.6.M supplies only the module-interface slice. A synthesis move may align required functions or functional-service claims under VP.Functional, flow or transduction topology under E.TGA, control structure under C.30.LCA, procedures and work packages under VP.Procedural, role enactors under VP.RoleEnactor, and modules or interfaces under VP.ModuleInterface; A.6.M repairs the module-interface relation, while non-module candidate generation, evidence, assurance, decision, work, and characteristic claims are governed by the patterns named in A.6.M:12 when those claims are being made.

moduleIn(...) relation record

Use moduleIn(...) only when the light repair note is not enough:

moduleIn(
  moduleHolonRef: U.HolonRef,
  wholeHolonRef: U.HolonRef,
  boundedContextRef: U.BoundedContextRef,
  viewpointRef: U.ViewpointRef = VP.ModuleInterface,
  boundaryRef: BoundaryRef,
  interfaceSpecRef: InterfaceSpecificationRef,
  functionalCorrespondenceRefs?: FinSet(CorrespondenceRef | KindBridgeRef),
  tgaFlowRefs?: FinSet(PathSliceId | TransferRef | CrossingRef),
  mechanismRefs?: FinSet(MechanismRef),
  dependencyRefs?: FinSet(QualifiedRelationRecordRef),
  substitutabilityPolicyRef?: EpistemeRef,
  variabilitySlotRefs?: FinSet(SlotRef),
  evidencePathRefs?: FinSet(EvidencePathRef),
  admissibleUse,
  nonAdmissibleUse
)

Well-formedness: the relation names both holons, one bounded context, one module-interface viewpoint, one boundary, and an interface specification or explicit interface-specification gap. Optional evidence, mechanism, and policy fields are used only when the corresponding evidence, mechanism, policy, conformance, or reliance claim is being made.

Interface specification is not a label

InterfaceSpecificationRef is the local specification reference for an interface specification. It may include:

InterfaceSpecificationRef:
  signatureRefs?: FinSet(SignatureRef)
  slotSpecSetRefs?: FinSet(SlotSpecSetRef)
  portEndpointSpecRefs?: FinSet(PortEndpointSpecRef)
  protocolOrSchemaRefs?: FinSet(EpistemeRef)
  admissibilityConditions:
  semanticConditions:
  versionOrChangePolicyRef?:
  conformanceExpectationRefs?:
  evidencePathRefs?:
  nonAdmissibleUse:

A signature declares vocabulary, laws, and applicability. A slot or endpoint record names positions and field structure. A protocol or schema constrains interaction. A mechanism reference can substantiate a realization relation. Evidence paths and conformance expectations can substantiate reliance only when an evidence path named by value or an assurance claim is being made. None of these, alone, is the module interface.

Repair applications for overloaded words

Source wordingGoverning repair application
componentFirst recover an A.14 relation such as ComponentOf, ConstituentOf, PortionOf, MemberOf, or PhaseOf. Apply A.6.M only when a module-interface relation is being claimed.
moduleRecover moduleIn(...) or ModuleRelationRepairNote over U.Holon refs under VP.ModuleInterface.
functional elementKeep under VP.Functional, A.6.F, or FunctionalStructureView@Context; connect to module-interface structure only through correspondence or allocation.
work package, delivery unit, or team boundaryKeep work, method, work-plan, role-assignment, role, and enactor claims with A.15, A.2, VP.Procedural, or VP.RoleEnactor when the wording asserts those claim kinds. Relate them to module-interface structure only through declared correspondence, allocation, or boundary relation.
deployment scope or placementRecover a deployment or placement structure under C.30 or C.30.ASV when that deployment or placement structure is being claimed. Relate it to module-interface structure only through declared correspondence or boundary relation.
interfaceRecover InterfaceSpecificationRef, not a wire, API label, port label, E.18 transduction relation, or function by itself.
signatureKeep as A.6.0 declaration. It is not an implemented interface, mechanism, gate, evidence row, or substitution policy.
port or endpointRecover SlotSpec, endpoint field, or interface-specification field when the claim is being made. It is not a module, graph edge, TGA crossing, or proof of integration.
functional linkKeep under VP.Functional or FunctionalStructureView@Context; relate to modules only through declared correspondence, allocation, or retargeting.
E.18 transduction relation or pathKeep under E.18 and C.30.TGA-FLOW-REL; it may inform an architecture-flow description, but it is not an interface specification.
platformRecover PlatformGrammarRef: extension rules, variability slots, interface specifications, substitution policy, and conformance expectations when platform extension, variation, substitution, or conformance use is being claimed.
stratification or architecture-operation source labelApply C.30.STRAT first. Use A.6.M only when the recovered result is a module-interface relation, interface specification, platform grammar, substitution or change policy, or open-architecture module-interface claim. Otherwise apply C.30.LCA, C.30.ASV, A.6.F, E.18, C.16.P, C.29, C.2.P, or use ordinary source-label disposition when no FPF-governed claim remains.
open architectureRecover OpenArchitectureClaim@Context: published interface specifications, substitution rules, change policy, data-rights or access constraints when those constraints are part of the open-architecture claim, and conformance expectations or evidence paths when reliance is being claimed.

First repair sequence

  1. Name the phrase and the practical situation.
  2. Select the whole holon and candidate module holon.
  3. State whether the source phrase is module relation, component relation, function allocation, procedural or work-package relation, role or enactor relation, deployment or placement structure, interface specification, signature, port or endpoint, TGA flow crossing, mechanism realization, platform grammar, control relation, autonomy-like operation claim, C.30.STRAT source-label case, or open-architecture claim.
  4. State the boundary and the declared interface specification or explicit interface-specification gap.
  5. State the admissibility conditions and substitution or change policy, or mark them not established by the repair.
  6. State the governing pattern for any non-module claim being made: C.30, C.30.ASV, A.6.F, A.15, A.2, E.18, C.30.TGA-FLOW-REL, C.31, C.31.RSA, C.16, A.10, B.3, A.20, A.21, C.28, E.20, G.5, or C.11.
  7. Stop when the relation and next move are explicit.

Worked slices

Ports line up.

Phrase:
  "The ports line up, so the modules are compatible."

ModuleRelationRepairNote:
  wholeHolonRef: VehicleControlSystem
  candidateModuleHolonRef: BrakeControllerPackage
  boundedContextRef: Release-2026Q2
  boundaryRef: BrakeControlBoundary
  interfaceSpecificationRef or gap: endpoint names present; protocol and semantic conditions missing
  admissibilityConditions: not yet declared
  substitutionOrChangePolicyRef: missing
  claimBoundary: interface-spec repair; no evidence or gate claim yet
  notAModuleBecause: port labels alone do not establish implemented interface compatibility
  governedNonModuleClaimPatternRefs: A.6.5, A.6.B, then A.6.M only if a substitution claim remains
  stopCondition: endpoint slots and missing interface-spec fields are visible

Open platform claim.

Phrase:
  "This is an open platform."

OpenArchitectureClaim@Context:
  architectureClaimRef:
  platformGrammarRef:
  interfaceSpecificationRefs:
  variabilitySlotRefs:
  substitutionOrChangePolicyRef:
  conformanceExpectationRefs:
  evidencePathRefs?:
  nonAdmissibleUse:
    "open" does not by itself prove substitutability, interoperability,
    assurance, procurement suitability, or architecture quality

The first slice repairs the claim without requiring measurement. The second slice applies MOSA-like conformance expectations and substitution policy only for the conformance or substitution claim being made.

Supplier-diversity, procurement suitability, use-context compatibility, business constraint, policy authorization, and provider-selection claims are not module-interface fields. If those claims are being made, A.6.M names only the module-interface slice; non-module selection, procurement, work, role, evidence, assurance, gate, release, and mechanism claims are governed by the patterns named in [A.6.M:12](/generated/patterns/A.6.M#relations).

Team boundary claim.

Phrase:
  "The team communication boundary matches the module boundary."

ModuleRelationRepairNote:
  wholeHolonRef: PaymentsPlatform
  candidateModuleHolonRef: SettlementService
  boundedContextRef: ProductLine-2026Q2
  boundaryRef: SettlementServiceBoundary
  interfaceSpecificationRef or gap: service API exists; semantic versioning, data schema, and semantic-constraint conditions incomplete
  admissibilityConditions: team delivery responsibility and on-call responsibility declared; substitutability not established
  substitutionOrChangePolicyRef: missing
  claimBoundary: role, enactor, work, and procedural correspondence first; module-interface relation only after boundary and interface specification are declared
  notAModuleBecause: team communication boundary and delivery responsibility do not by themselves establish module interface, substitutability, or compatibility
  governedNonModuleClaimPatternRefs: A.15 and A.2 for team and work claims; C.29 if the team/module correspondence is claimed as homomorphism-like or almost-same structure; A.6.M only for the declared module-interface relation
  stopCondition: the correspondence is usable as an architecture diagnostic, not as proof

The third slice uses Conway-like mirroring as a diagnostic prompt. It does not make organization structure, communication relations, or delivery responsibility into module-interface structure by identity.

Proxy-cost replay: if a repair proposes more modules, more open interfaces, or more parallel paths, name what may get worse before claiming improvement. Synchronization work, communication overhead, conformance work, shared-resource pressure, hidden exception cost, or cross-boundary change cost can become the claim being made. A.6.M repairs only the module-interface relation; speedup, bottleneck, modularity, measurement, work, and quality tradeoffs are governed by [C.29](/generated/patterns/C.29), [E.18](/generated/patterns/E.18), [C.31](/generated/patterns/C.31), [C.16](/generated/patterns/C.16), [A.15](/generated/patterns/A.15), or the related governing pattern named by value when that related claim is being made.

Lowering and Reopen Conditions

Lower an A.6.M repair to reduced-use cue, quote-only wording, blocked use, or incomplete rewrite when the module-interface relation, interface specification, admissibility conditions, or substitution or change policy cannot be stated by value.

Reopen the repair when any of these change: the whole holon or candidate module holon, the boundary, the interface specification or explicit gap, the substitution or change policy, the platform grammar, the conformance expectation, the evidence path relied on, the source-label recovery from C.30.STRAT, the team-boundary or work correspondence, or the governing pattern for a related claim being made.

If the reopened material is no longer a module-interface relation, A.6.M keeps only the previous repair as source context and the claim being made is governed by the pattern named in A.6.M:12.

Archetypal Grounding

Tell. A module is not a little box. It is a holon related to a larger holon under a declared boundary, interface specification, admissibility conditions, and substitution or change policy.

Show. A software package, neural-network block, chiplet, power converter, document template, or organizational unit can become module-like in a project only when the relation record says what whole it belongs to, what boundary it offers, what interface specification governs use, and what substitution or change policy makes replacement admissible.

Show. A port label, API endpoint or route label, flow edge, or function name may be a useful clue. It can substantiate a module-interface claim only after the relevant signature, slot, protocol, semantic condition, correspondence, mechanism, and evidence, conformance, source relation, or reliance relation named by value are declared.

Holon and episteme: the candidate module and whole are described holons under a module relation; they may be systems, epistemes, methods, organizations, publication families, or other structured holons. The module relation, interface specification, platform grammar, and open-architecture claim are Description epistemes, specification-use descriptions, or relation records about those holons. Stratification and architecture-operation labels named by C.30.STRAT remain source labels unless C.30.STRAT recovers a module-interface relation that A.6.M can use.

Bias-Annotation

Bias riskA.6.M repair
Box biasDo not treat a diagram box as a module. Recover holon, whole, boundary, and interface specification.
Open-label biasDo not treat "open" as substitutability. Recover standards, conformance expectations, data or access constraints, and change policy when those conditions are part of the claim being made.
Component biasDo not treat every part as a module. Apply A.14 to component wording unless a module-interface relation is being claimed.
Interface-label biasDo not treat API, port, endpoint, or signature labels as implemented compatibility. Recover InterfaceSpecificationRef.
Team-boundary biasDo not treat Conway-like mirroring, team responsibility, team communication boundary, or delivery-unit labels as module boundaries. Recover role, enactor, work, and procedural relations first; add module-interface correspondence only when the boundary and interface specification are declared.
Parallelism biasDo not treat decomposition into more modules, teams, services, or paths as performance or evolvability improvement. Recover serial work, synchronization, communication overhead, shared resources, and bottleneck claims through TGA, C.29, C.31, or neighboring characteristic patterns when those claims are being made.
Platform biasDo not treat a platform name as architecture quality. Recover platform grammar and the claim named by value it can substantiate.

Conformance Checklist

IDCheck
CC-A6M-1The text names the whole holon, candidate module holon, bounded context, and module-interface viewpoint, or explicitly stops at ordinary non-claim-bearing wording.
CC-A6M-2The repair states whether the phrase is a module relation, component relation, function allocation, procedural or work-package relation, role or enactor relation, deployment or placement structure, interface specification, signature, port or endpoint, TGA flow crossing, mechanism realization, platform grammar, control relation, autonomy-like operation claim, C.30.STRAT source-label case, or open-architecture claim.
CC-A6M-3No new root kind is minted for module, interface, platform, or open architecture; stratification or architecture-operation source labels use C.30.STRAT unless a module-interface relation has already been recovered.
CC-A6M-4InterfaceSpecificationRef is recoverable when interface compatibility, substitutability, or conformance is being claimed.
CC-A6M-5Substitution or change policy is declared when replaceability, alternate supplier, upgrade, or platform extension is being claimed. Substitutability not established by the repair is marked as not established, not implied by wording.
CC-A6M-6Function, TGA flow, control, work, evidence, assurance, gate, decision, causal, and mechanism claims use their governing patterns.
CC-A6M-7A failed check gives a repair move or governing-pattern application, not only a rejection.
CC-A6M-8A current G.2 source row for MOSA, open systems, platform practice, Conway correspondence, team-boundary correspondence, or Amdahl-style decomposition limits appears before guidance from that source is used for practitioner-facing claims being made.
CC-A6M-9RFC keywords are used only for pattern users, records, claims, conformance items, or publication records, evidence records, or assurance records. Modeled modules and interfaces are not written as agents with duties.
CC-A6M-10Lower or reopen the repair when whole/module holon, boundary, interface specification or gap, substitution or change policy, platform grammar, conformance expectation, relied-on evidence path, source-label recovery, team/work correspondence, or neighboring governing pattern changes.

Common Anti-Patterns and How to Avoid Them

Anti-patternSymptomRepair
BoxIsModuleA diagram box is treated as a module.Recover moduleIn(...) fields or downgrade the box to a publication face or structural view element.
SignatureAsInterfaceA signature declaration is treated as implemented compatibility.Keep signature under A.6.0 and add interface-specification fields only when interface compatibility is being claimed.
PortAsProofMatching port or endpoint names are treated as integration proof.Recover slot specs, protocol or schema, semantic conditions, and evidence, conformance, source relation, or reliance relation named by value.
FunctionalLinkAsInterfaceA functional relation is treated as module boundary.Keep VP.Functional and add correspondence or allocation only when module allocation or correspondence is being claimed.
OpenByPublicationOnlyPublished interface text is treated as open architecture.Add substitution policy, conformance expectations, change policy, source or evidence relation, and data or access constraints when those conditions are part of the open-architecture claim; non-module selection, procurement, work, evidence, assurance, gate, mechanism, and decision claims are governed by the patterns named in A.6.M:12.
TeamBoundaryAsModuleA team boundary, team responsibility label, communication boundary, or delivery unit is treated as a module interface.Recover A.15, A.2, VP.Procedural, or VP.RoleEnactor; add A.6.M only for the declared module-interface relation; use C.29 when a homomorphism-like correspondence claim is being made.
MoreModulesMeansBetterMore modules, teams, services, threads, or parallel paths are treated as automatic improvement.Recover serial work, synchronization, communication overhead, shared resources, and bottleneck claims; mathematical speedup or homomorphism claims are governed by C.29, and characteristic tradeoffs are governed by C.31 and C.16.
PlatformAsKindA platform label becomes a root kind or quality claim.Use PlatformGrammarRef and apply governing patterns for quality, measurement, and decision claims.
StackAsArchitectureA stack diagram is treated as the architecture itself or as a module-interface relation by label.Apply C.30.STRAT first; then use C.30 or C.30.ASV for architecture or structural-view use, A.6.M only for a recovered module-interface relation, or ordinary source-label disposition.

Consequences

Benefits:

  • Module and interface talk becomes usable without minting false root kinds.
  • Practitioners get a cheap relation repair before measurement or evidence work.
  • MOSA and open-system claims become precise enough to make real substitution and change reasoning admissible.
  • Functional, flow, control, mechanism, work, evidence, assurance, gate, decision, and causal claims stay with their governing patterns.

Costs:

  • Ordinary architecture prose loses the convenience of treating boxes, ports, interfaces, and modules as one kind.
  • Interface claims sometimes require additional records before substitutability can be relied on.
  • "Open architecture" becomes harder to claim because interface publication alone is not enough.

Rationale

The central decision is to treat module as a context-sensitive and viewpoint-sensitive relation role of U.Holon, not as a new root kind. This keeps FPF compatible with many engineering contexts where the same system, episteme, method, organization, publication family, or other structured holon can be a component under one declared relation, a module under another, a functional element under another, and an evidence, assurance, source, or publication artifact under another.

A.6.M follows A.6.P: overloaded relation language is repaired by reconstructing kind, slots, qualifiers, admissible use, and witnesses. It also follows the architecture relation discipline: boundary notes catch the first confusion, while A.6.M supplies the full repair body for module relation, interface specification, substitutability, change policy, and open-architecture conformance and admissible-use claims.

The pattern deliberately keeps measurement out of the first move. A module relation can be repaired before anyone knows whether external coupling density, interface standardization share, evidence reuse, or reusable-structure accounting will be needed. When those claims are being made, A.6.M applies C.31, C.31.RSA, and C.16.

SoTA-Echoing

Source or practiceCurrentness or lineage useAdoptAdapt for FPFReject or boundaryPractitioner implication
DoD OUSD(R&E) MOSA guidance and implementation guidebook (https://www.cto.mil/sea/mosa/; https://www.cto.mil/wp-content/uploads/2025/03/MOSA-Implementation-Guidebook-27Feb2025-Cleared.pdf)Current official acquisition and engineering practice family for open modular systems; used as current practice guidance, not as a complete FPF ontology.Modular design, interface standards, conformance verification, replacement or change policy, and competitive reuse are real conformance and substitution expectations.Recover them as InterfaceSpecificationRef, PlatformGrammarRef, substitutionOrChangePolicyRef, conformance expectation, source relation, and evidence path only where the recovered claim needs them; non-module selection, procurement, policy, evidence, assurance, gate, decision, work, role, enactor, and mechanism claims are governed by the patterns named in A.6.M:12.Do not treat open, interface publication, or modular-looking structure as substitutability, assurance, procurement suitability, supplier-set selection, policy authorization, quality proof, or decision authority.A practitioner asking whether something is open first repairs the relation and the interface specification; non-module claims are governed by related patterns governing those claims when those claims are being made.
Conway's law, the mirroring hypothesis, and Team Topologies and inverse Conway practice (https://www.melconway.com/Home/Committees_Paper.html; https://doi.org/10.1016/j.respol.2012.04.011; https://itrevolution.com/wp-content/uploads/2022/06/TTOP_excerpt.pdf)Mature socio-technical law and empirical lineage plus current organization-design practice family; used as diagnostic pressure, not as a proof rule.Team communication structure, team-boundary placement, and delivery responsibility can create real pressure on module and interface boundaries and useful correspondence clues.Recover team and work material through A.15, A.2, VP.RoleEnactor, or VP.Procedural first; connect it to ModuleInterfaceStructure only through declared correspondence, allocation, boundary relation, and preserved and lost structure note. Use C.29 when the correspondence is claimed as homomorphism-like or almost-same structure.Do not treat Conway's law, an org chart, team responsibility label, or a delivery unit as proof of module interface, substitutability, modularity quality, evidence, gate passage, or architecture decision.A practitioner may use team-boundary mismatch as a diagnostic prompt: repair the role, work, and module relation, then decide whether the module boundary, team boundary, communication relation, or architecture move changes.
Amdahl's law and communication and synchronization extensions (https://www.cs.cmu.edu/~18742/papers/Amdahl1967.pdf; https://arxiv.org/abs/1306.3302; https://arxiv.org/abs/2603.20654)Mature mathematical law plus current extension sources for communication, synchronization, and scalable-workload-fraction limits.Serial work, synchronization, communication overhead, shared resources, and changing scalable workload fractions can limit the payoff of decomposition, parallelization, or specialization.Use C.29 for mathematical speedup or value-scalable-fraction reasoning, E.18 and TGA for flow and crossing structure, and C.31 and C.16 for modularity and characteristic tradeoffs.Do not treat module count, team count, service count, parallel-path count, or accelerator count as improvement, scalability, throughput, or evolvability by itself.A practitioner considering a module split names the serial part, shared bottleneck, synchronization or communication overhead, and characteristic tradeoff before claiming improvement.
SEI Views and Beyond, ISO/IEC/IEEE 42010:2022, and multi-view architecture practiceMature architecture-description lineage plus current international view-description discipline; not used as a current module-quality source.Module and component-and-connector views are distinct architecture descriptions.Use ModuleInterfaceStructure and RuntimeInteractionStructure as structure-kind signals under C.30.ASV.Do not reduce architecture to a module diagram.Module repair stays one architecture-structure concern, not the whole architecture ontology.
Platform and product-line engineering practice (https://tag-app-delivery.cncf.io/fr/whitepapers/platform-eng-maturity-model/; https://www.sei.cmu.edu/library/variability-in-software-product-lines/; https://arxiv.org/abs/2605.21353)Mature product-line variability lineage plus current platform-engineering maturity-model and current SPLE-review cues; used for variability-slot and extension-rule discipline, not as one FPF platform kind.Variation slots and extension rules matter for reuse and substitution.Use PlatformGrammarRef, variabilitySlotRefs, and change policy instead of a platform root kind.Do not treat platform name as architecture quality, architecture scale-preference evidence, procurement suitability, supplier-set selection, or decision authority.The next move is to identify extension rules and substitution conditions; non-module quality, scale-preference, procurement, supplier-set, and decision claims are governed by the patterns named in A.6.M:12 when those claims are being made.
Architecture-operation language, with neural-network and software-system intakes as source examplesCurrent practitioner-language source examples accepted by the architecture workstream; used as recognition material, not as a standard or current-best-known authority.C.30.STRAT source labels, including source examples such as block, layer, expert, router, cache, and state, are useful recognition prompts.Keep them as source labels until the recovered FPF kind, relation, claim-use, or source-use disposition is known; use A.6.M only for module-interface relation, interface specification, platform grammar, substitutability, or open-architecture module-interface claims.Do not import source-context labels as module kinds or evidence of adequacy.The same repair works for neural-network block replacement, hardware module substitution, organizational module repair, and episteme-module repair without making any source context the ontology.

Older or local sources may serve as lineage or worked examples only when the row says so. They do not stand in for current competitive source, and they do not make a module, interface, platform, or open-architecture claim admissible for comparison, assurance, gate, selection, or decision use without the governing pattern for that use.

Relations

PatternRelation
A.6.PA.6.M is an RPR specialization for module-relation and interface-specification language.
C.30.STRATRecovers stratification and architecture-operation source labels before A.6.M governs only recovered module-interface relation cases.
E.16Governs autonomy-budget, autonomous operation, independent acting, unsupervised decision or action, and freedom-of-action claims when those description or view uses are being made; A.6.M keeps only the module-interface relation, boundary, interface specification, and substitution or change-policy slice.
A.14Component and part-whole wording uses A.14 first unless a module-interface relation is being claimed.
A.6.0 and A.6.5Signatures, slots, ports, endpoints, and field structure remain governed by signature and slot discipline.
A.6.B, A.6.C, and A.6.8Boundary, interface-specification, API, protocol, service, promise, and duty wording uses A.6.M only when the claim is module-interface relation, interface specification, substitutability, change policy, platform grammar, or open-architecture module-interface claim.
C.30 and C.30.ASVArchitecture claims and module-interface structural views stay architecture-governed.
A.6.FFunction and functional wording stays distinct from module allocation.
A.15 and A.2Method, work-plan, performed-work, role-assignment, role claims, enactor claims, team-boundary wording, and delivery-unit wording are governed by A.15, A.2, VP.Procedural, or VP.RoleEnactor unless a module-interface relation or correspondence is recovered; A.6.M governs only that recovered module-interface slice.
E.18 and C.30.TGA-FLOW-RELE.18 transduction relations, path slices, crossings, and flow valuations are not interface specifications.
C.31Modularity and reusable-structure characteristics are governed by C.31 after relation repair when characteristic or measurement use is being made.
C.31.RSAReusable-structure accounting is governed by C.31.RSA when reusable loci, bespoke residue, or report-only share claims are being made.
C.16Measurement, score, scale, unit, comparability, and evidence-stub legality remain C.16-governed.
A.10, B.3, A.20, A.21, C.28, E.20, G.5, C.11Evidence, assurance, gates, causal use, mechanism suites, set-return selection, and local decisions use their governing patterns; they are not A.6.M claims.

A.6.M:End


Last Updated: 2026-06-03 — this section last modified in upstream FPF commit a0c90e3b (github.com/ailev/FPF)