Operational specification

Quick & Dirty Fix: the Triple Crown.

A bounded, contract-driven approach to automating one recurring operational friction using CMMN for context, BPMN for prescribed behavior, and DMN for decision logic.

1. Definition of a Quick & Dirty Fix

A Quick & Dirty Fix (QDF) is a deliberately narrow, contract-driven automation intervention that removes one recurring operational friction within an existing workflow. It is neither careless implementation nor a disguised platform programme. “Quick” means that its request, operation, outcome, and value can be understood promptly. “Dirty” means pragmatic and intentionally limited: it implements only the controls needed for its stated operational boundary.

A QDF has an explicit trigger, defined input and output contracts, a limited execution boundary, observable results, isolated failure handling, and a clear stopping condition. Its contract says both what it will do and what it will refuse, defer, or hand to a person. A QDF can contain more than one activity when the activities are inseparable for its bounded outcome; it should not acquire unrelated workflow responsibilities.

2. Problem class

QDFs address recurring, low-to-moderate-complexity operational friction where a durable product or broad workflow redesign would be disproportionate. Examples include extracting fixed fields from repeated requests, checking a configuration against policy, preparing a constrained draft, routing an intake item, or assembling a regular operational summary.

The problem needs a recognizable demand signal, sufficiently stable inputs, a useful observable outcome, and a tolerable failure mode. It is a poor fit for open-ended judgement, long-running cross-team coordination, unrestricted authority, or an unbounded set of integrations.

3. Essential properties and boundaries

PropertyRequired operational meaning
TriggerA request, event, schedule, or condition explicitly starts execution. Demand-triggered operation is normally preferred.
ContractsInputs define required data, validation, caller responsibility, and permitted effects; outputs define result, status, evidence, and recipient.
BoundaryThe QDF owns only its stated work, data, integrations, and authority.
ObservationCorrelation ID, status, outcome, and material error evidence make each execution inspectable.
Failure containmentA failure terminates, compensates, or routes only the affected execution.
Stop conditionCompletion, rejection, cancellation, failure, or documented human handoff is terminal.

Stateless decision logic and short-lived execution state are preferred because they simplify replay and replacement. Durable case state is justified when the QDF must wait for events, retain evidence, or coordinate review.

4. BPMN: prescribed process behavior

BPMN specifies prescribed process behavior. It defines the start event, ordered activities, service interactions, gateways, success path, error path, and end events. It answers: when this execution is started, what flow is performed and how does it complete?

BPMN pseudomodel
  1. Message start event Valid demand
  2. Service task Validate input contract
  3. Business rule task Evaluate DMN eligibility
  4. Eligible?
    No Send rejection → End: rejected
    Yes Execute bounded work → Validate output → Deliver outcome → End: completed
  5. Boundary error on bounded work: record isolated failure → report failure or request review → End: failed or handed off

Use BPMN to make the operational path executable or reviewable, including boundary error events and explicit completion. It does not model a request’s full evolving context or a large table of business policy.

5. CMMN: case context

CMMN specifies case context. It defines the execution instance, case file and data, event-driven work, discretionary interventions, milestones, and criteria that make work available. It answers: what is known about this specific situation, what may happen next, and what work becomes available as events and data change?

CMMN pseudomodel
Case: QDF execution caseCase file: input · eligibility · work result · output · observationsSentry: input validated → “Run bounded BPMN process” available
Discretionary human taskReview ambiguous result
MilestonesEligibleOutcome deliveredReview required
Exit criterionCancelled demand → terminate case

Use CMMN when the QDF needs contextual state, such as an intake case awaiting evidence, a reviewer’s intervention, or a delivery milestone. A CMMN task may invoke a BPMN process; it does not replace the detailed sequence of that process.

6. DMN: decision logic

DMN specifies decision logic. It defines stateless business rules, eligibility checks, routing, thresholds, classifications, and outcome selection. It answers: given declared inputs, what decision outcome applies?

Decision table: determine handling
inputValidconfidencerestrictedContentoutcome
true≥ 0.90falseAUTOMATE
true0.60–0.89falseHUMAN_REVIEW
trueanytrueREJECT
falseanyanyREJECT

Use a DMN decision service for policy that must be inspectable and independently testable. It receives declared facts and returns a result; it does not create a case, execute service calls, or manage exceptions.

7. Unified Triple Crown operating model

One bounded QDF keeps the request context, prescribed execution, and policy outcome distinct while sharing explicit contracts, observations, and a terminal condition.

Triple Crown integration — one QDF contract, three focused responsibilities
Triple Crown integration inside a bounded QDF contractCase context enables a process, the process calls a decision service, and all three use declared contracts. Bounded QDF contractdeclared scope · authority · observation · stopping condition CASE CONTEXTCMMN case modelfacts · evidence · sentriesmilestones · available work PROCESS CONTROLBPMN process modelprescribed path · gatewaysboundary errors · delivery DECISION LOGICDMN decision servicedeclared facts inAUTOMATE / REVIEW / REJECT out process task invokeswhen availablebusiness rule invokesdecision outcome Input · output · observation contractsvalidated facts, permitted effects, evidence, recipient, terminal status CMMN enables the process; it does not prescribe its flow.DMN returns a result; it does not own case or process state.

8. UML diagram set

These diagrams show how the QDF is specified, assembled, run, observed, isolated on failure, and brought to a terminal outcome.

Component architecture — the bounded operating surface
QDF ownership boundaryRequesterdemandExternal systems Trigger /IngressInputcontractCase context(CMMN)ProcesscontrollerDecisionserviceConstrainedwork unitpermitted call Delivery / outputrecipient + statusMonitoring & error reporting — correlation ID · status · evidence outcometrace

Ingress accepts the demand, contracts constrain it, case context makes work available, and only the controller can command bounded work and delivery.

Execution activity lifecycle — success, review, and isolated failure
StartReceive demandValidate inputValid?Create caseDMN eligibilityEligible?yes Reject malformedinputnoDeliver rejectionno Execute bounded workFailed?yesContain + recordfailure evidenceyesReview?Human reviewReport failure Validate resultSufficient?Deliver + endno — request review
Runtime sequence — one correlation ID across success and isolated failure
RequesterIngressControllerCaseDMNWorkDeliveryOperator SUCCESS PATHdemandvalidated input + correlation IDcreate / update caseevaluate eligibilityAUTOMATEexecute bounded commandvalid resultdeliver outcomeoutcomerecord completed FAILURE PATH — ISOLATED TO THIS EXECUTIONdemandvalidated input + correlation IDcreate / update caseevaluate eligibilityAUTOMATEexecute bounded commandfailure evidencerecord failed / isolatealert with correlation IDdeliver failure noticefailure / review notice
Execution state machine — stopping conditions are explicit
Receiveddemand capturedValidatedinput contract passedEligibleDMN = AUTOMATEExecutingbounded workacceptedautomate Rejectedinvalid or deniedAwaiting reviewhuman decision neededFailedisolated + recordedCompleteddelivered + recordedCancelleddemand withdrawn invalidreviewerrorresult + deliveryapprovedeclinedemand withdrawn
Conceptual class model — contracts own the QDF boundary
QuickDirtyFix+ name: String+ executionBoundary · stoppingConditionExecutionCase+ correlationId: String+ status: ExecutionStatusInputContract+ validate(input): ValidationResultProcessDefinition+ coordinate(case): ResultErrorBoundary+ contain(error): ResultDecisionService+ evaluate(facts): OutcomeWorkUnit+ execute(command): ResultExecutionResult+ status · evidenceObservation+ timestamp · event10..*invokescommandscreatesproducesrecordsInvariantScope, authority, and terminal outcome are declared.

9. Worked operational example

Intake takeaway curator. A team receives meeting notes and needs a concise, owner-tagged takeaway email. The QDF starts only for the recognized “curate takeaways” trigger with notes and a recipient. Inputs require non-empty notes, an authorized requester, and a delivery target; outputs include a correlation ID, structured takeaways, delivery status, and any review reason.

AI is a constrained processing capability: it receives approved notes and formatting instructions, returns a schema-conforming draft, and has no authority to choose recipients, manage the case lifecycle, invoke arbitrary tools, or decide delivery.

10. Principles, constraints, and anti-patterns

Principles and constraints

  1. Narrow and localized scope: remove one named friction; keep authority and integrations local.
  2. Demand-triggered execution: prefer an explicit request or event unless a schedule is the actual contract.
  3. Minimal necessary complexity: model paths, data, and controls needed for safe operation.
  4. Explicit contracts: validate inputs, outputs, permissions, time limits, and side-effect boundaries.
  5. Stateless decisions where possible: use declared facts and retain case state only when context needs it.
  6. Fail fast and visibly: preserve a clear reason and correlation ID.
  7. Contain failures: scope retries, alerts, compensation, and review to one execution.
  8. Integrate rather than replace: use existing tools and handoffs through explicit interfaces.
  9. Replaceability: make the QDF easy to retire, revise, or promote.
  10. Constrained AI: limit inputs, outputs, permissions, and validation.

Anti-patterns

11. Conclusion

A QDF is a bounded engineering intervention: a small contract that converts a known demand into one observable terminal outcome without taking ownership of the surrounding enterprise workflow. The Triple Crown makes that contract precise through CMMN context, BPMN behavior and failure paths, and inspectable DMN decision logic.