All chapters
  1. Start hereEnterprise AI adoption strategy, stage by stage and role by role
  2. Chapter 1Why AI adoption stalls
  3. Chapter 2Governance is the first enabler
  4. Chapter 3Who decides, who runs it
  5. Chapter 4Finding the right use cases
  6. Chapter 5The adoption ladder
  7. Chapter 6Role tracks
  8. Chapter 7Reuse first, as code
  9. Chapter 8The worked example
  10. Chapter 9The enablement program
  11. Chapter 10Measuring adoption honestly
  12. Chapter 11Evaluating and mapping tools
  13. Chapter 12Hands-on labs
  14. Chapter 13Templates, each filled
  15. Chapter 14Glossary
  16. AboutAbout this site
Role track · Data & platform

Data engineer and steward

Authoritative sources, lineage, classification and retrieval corpora that are fit for AI before any model sees them.

The data engineer decides how data reaches an AI step, and proves where it came from. This track covers two jobs that share one pipeline but hold different decisions. The data engineer and the analytics engineer build and run the pipeline. The data steward and the data owner decide definitions, permitted purpose, access and quality thresholds.

A model, a retrieval index or an evaluation set is only as trustworthy as the data behind it. Numbers on this page are illustrative.

1. At a glance

FieldAnswer
MandateOnly authoritative, classified, permitted and current data reaches a model, a retrieval index or a test, with data lineage to prove it
Primary outcomeA data flow a risk partner can trace from source to answer, approved by the data owner for this purpose
First safe winUse the approved assistant to draft documentation and data-quality rules from schemas and metadata, never from records
Biggest failure modeAI quietly "repairs" bad data (for example, guesses a missing time zone) instead of the gap going to the data owner

Line: 1st line · Family: Data & platform · Variants: data engineer, analytics engineer, data steward, data owner

VariantWhat differs
Data engineerBuilds ingestion, indexing and reconciliation pipelines. Owns pipeline code, tests and run evidence
Analytics engineerBuilds the data models, metrics and dashboards that monitoring and the adoption scorecard read. Owns metric definitions in code
Data stewardOwns the definition, classification and quality rules of a data element. Recommends whether it fits a purpose. Does not build the pipeline
Data ownerThe accountable business owner of a dataset. Approves access and permitted purpose, and accepts or rejects quality exceptions

2. Your journey: first steps to fully adopted

This is the path from your first month to a fully adopted way of working. The order of the steps is the same in any organization; only the weight of the controls changes.

Start here: your first steps

  1. Register every source that feeds AI with its class, owner and permitted purpose in the source register.
  2. Draft documentation and quality rules with the approved assistant from schemas and metadata only, never from records.
  3. Write the data rules section of the team instructions file: authoritative sources, banned conversions, data classes.
  4. Replace any production sample in tests with synthetic fixtures, checked by a real-value scan.

Fully adopted: how the work runs

Moment in the workBefore AIFully adopted (Stage 4–5)Decision that stays human
New data needSomeone exports a table or a shared-drive folderThe source register names the authoritative source, class and permitted purpose before any pipeline existsThe data owner approves the purpose; privacy is consulted
Pipeline buildHand-written pipeline; lineage drawn from memoryAn agent drafts pipeline changes, quality checks and lineage as pull requests; generated checks must catch seeded defectsA second engineer approves; the steward approves rule changes
Retrieval indexBuilt once from whatever was at handRebuilt in staging on each approved policy notice, with an index manifest (version, hash) and an evaluation runThe policy office confirms content; the release manager approves promotion
Data gap foundA script or AI "repairs" missing values silentlyThe gap goes to the data owner as an exception with an expiry; the fallback is labelled on screenThe data owner accepts or rejects the exception
Run and retireWithdrawn documents stay retrievableContinuous freshness checks; deletion propagation proved with a seeded document; data lineage in the catalogRecords management sets retention; data owners review on cadence

What changes for the organization

BeforeAfter
Nobody can say which data a model sawEvery AI answer traces back to an authoritative, approved source
Data gaps are patched quietlyData gaps are owned decisions with an expiry date
Tests copy production dataTests run on synthetic fixtures; no customer data sits in any test

In any organization

3. Your decisions

"Cannot be delegated" means the decision stays with a named person: an AI step may prepare the inputs, never make the call.

DecisionYour relationshipInputsEscalationCannot be delegated
Which source is authoritative for a data elementEngineer advises; steward recommends; data owner ownsService catalog, data catalog, architecture decisionData owner; architect for service boundariesYes
Whether data may enter a prompt, index or evaluation setEngineer advises; steward classifies; data owner approves the purpose; privacy is a consulted control partnerClassification, intake card, privacy assessmentPrivacy officeYes
Pipeline design: ingestion, provenance, freshness SLA (service level agreement)Data engineer ownsSource change rate, consumer needs, platform golden pathArchitect, platform engineerNo; AI may draft, a reviewer approves the pull request
Quality thresholds per slice and what happens below themSteward owns; engineer implementsConsumer impact, historical profilesData ownerYes
Accepting a quality exception (a known gap, such as missing zones)Engineer challenges; data owner ownsProfiling result, customer impact, expiryData owner; risk partner when customers are affectedYes
Deletion and retention propagation into indexes, caches and copiesEngineer owns the mechanism; records management sets the ruleRecords schedule, legal hold noticesRecords managementYes
Removing a withdrawn document from a retrieval indexPolicy office decides; engineer executes and verifiesPolicy version noticePolicy officeNo; automated on notice, verified by test

4. Two kinds of adoption

KindWhat it looks likeGuardrail
How you work with AIThe assistant explains an unfamiliar schema, drafts SQL (structured query language) and transforms, writes data-quality rules and lineage notes, summarizes a profiling reportSchemas, metadata and synthetic samples only. No records in prompts. Every change lands as a reviewed pull request
What you build that feeds AIRetrieval corpora and indexes, evaluation datasets, synthetic test fixtures, monitoring datasets, data products a model readsLineage, provenance, permitted purpose, minimization, freshness, deletion propagation, reconciliation

The second row is the larger risk. A model inherits every defect of its data, and a retrieval index turns a stale document into a confident, cited answer.

5. Your ladder

StageAI useGuardrailArtifact or evidenceDecision relationshipStep-down trigger
0 · FoundationsNoneData classification rules; named steward and owner per source; access and loggingSource register: each source with class, owner, permitted purposesData owner approves; privacy consultedA source with no named owner
1 · Personal productivityExplain schemas; draft queries and docs from metadataMetadata only; secrets and PII (personally identifiable information) block on promptsReviewed query, documentation pageEngineer owns; peer reviewerA record pasted into a prompt (a near miss, reported)
2 · Team contextAssistant reads the team's data rules: authoritative sources, banned conversions, classesData section of the instructions file, reviewed like codeInstructions file "data rules" sectionSteward reviews the data rulesSteward rejects a definition the file states
3 · Delegated tasksAgent drafts pipeline changes, quality checks, lineage docs and synthetic fixtures as pull requestsEvaluation set: generated checks must catch seeded defects; fixtures must contain no real valuesPull request, evaluation run, lineage recordSecond engineer approves; steward approves rule changesA generated check misses a seeded defect
4 · Agentic workflowsOn an approved policy version notice, the workflow rebuilds the index in staging, runs the evaluation and opens a promotion changeLeast privilege: read approved sources, write the staging index only; promotion by a personIndex manifest, evaluation report, change recordPolicy office confirms content; release manager approves promotion; AI risk notifiedEvaluation fails; source schema changes; embedding model changes
5 · Scale and sustainShared ingestion golden path; lineage in the catalog; continuous freshness checksPipeline ownership and funding; periodic reviewCatalog entries for pipelines; freshness dashboardData owners review on cadenceNew source or new purpose (material change)

Human-operated at Stage 5. Approving a new purpose for a dataset and accepting a quality exception stay with the data owner at every stage. AI may draft the impact summary. It never decides.

6. Priority scenarios

ScenarioValueRisk tierStageFirst stepDo not use AI when…
Catalog documentation from schemasCatalog coverage rises without a documentation sprintMedium1Export metadata only; the steward reviews each entryThe schema itself is classified restricted
Data-quality rules from a profile summaryMore checks, found earlierMedium3Evaluation set of seeded defects the rules must catchThe rule encodes a business definition the steward has not approved
Policy assistant indexGrounded, cited answers for staffMedium3 to 4Ingest only approved, versioned documents with a manifestThe source is email, chat, a shared drive or a draft
Synthetic test fixtures for QA (quality assurance)No customer data in any testMedium3Generate from the schema and the rules; scan for real values"Realistic" seems to need real records
Lineage for impact analysisFaster, evidenced impact analysisMedium2 to 3Assistant reads the lineage graph and code, cites each edgeThe lineage graph has gaps: run a deterministic scan, do not let AI guess edges
Channel reconciliationMismatches found before customers find themLow (no AI in the check)n/aDeterministic comparison against the sourceAlways for the comparison itself. AI may only explain a mismatch a query found
Filling missing values (zones, dates)None that justifies the riskHigh if proposedn/aRoute the gap to the data ownerAs a silent repair, ever. A deliberate proposal goes through intake as High

7. The due-date ask from your seat

The data engineer changes nothing in payment-schedule-service or profile-service. Both are read-only, authoritative sources for this change. The role's work is evidence: where the data comes from, how good it is, and whether the channels agree after release.

DecisionInput receivedOutput and evidenceRecipient
Which datasets carry the due date, and as what typeImpact analysis question from the architect and BA (business analyst)Lineage record: payment-schedule-service is the source; four display channels read it; the warehouse copy stores a date type. A copy stored as a timestamp would be a separate finding for its data owner, not part of this changeArchitect, BA
How complete is the zone preferenceFallback rule (state of residence) from the PO (product owner) and complianceProfile completeness by state: share of profiles with no IANA (Internet Assigned Numbers Authority) zone. The steward sets the threshold; the data owner accepts the known gap with an expiryPO, data owner
Synthetic fixtures for the test matrixTest cases T1 to T13 from the QA engineerFixtures generated from the schema: zones, DST (daylight saving time) weeks, a missing zone, an issued statement. A scan confirms no real account valuesQA engineer
Channel consistency monitorMonitoring signal defined by the teamA deterministic daily job: 1,000 sampled accounts, due date on each channel compared with payment-schedule-service. Zero mismatches expectedProduction support, PO
# data-contract.yaml · payment due date · v1 (illustrative)
element: contractual_due_date
source: payment-schedule-service      # authoritative, read-only for this change
type: date                            # date-only value; never converted to an instant
steward: payments data steward
owner: payments business owner
consumers: [web, mobile, statement-service, notification-service, warehouse]
quality:
  - rule: not_null
  - rule: no_time_component
element: payment_cutoff
type: instant                         # shown in the customer's IANA zone at display time
zone_source: profile-service
fallback: state_of_residence_zone     # labelled on screen; gap accepted by owner until 2027-03-31

Companion: the policy assistant index. Here the data engineer holds a material artifact. The index is the trust boundary's source list: if a document is in it, the assistant can cite it. The engineer ingests only approved, current documents from the policy library, records a version and hash for each, and removes withdrawn versions on the policy office's notice.

# index-manifest.yaml · policy assistant · build 2026-10-28 (illustrative)
corpus: approved-policy-library
embedding_model: approved-embedding-v3    # a change here is a material change
documents:
  - id: POL-PAY-014
    version: 7
    sha256: 9f2c...e1
    status: current
    approved_by: policy office
  - id: POL-PAY-014
    version: 6
    status: withdrawn
    removed_from_index: 2026-10-21       # deletion propagation verified by test
checks:
  injection_scan: passed                 # text that reads like instructions is flagged for the owner
  stale_slice_eval: passed               # withdrawn version is never cited

The QA engineer and AI engineer run the evaluation against this manifest. Independent validation can rebuild the same index from it. See the worked example for the evaluation set and the trust boundary.

8. Hand-offs and separation of duties

You give → to whomYou receive ← from whomYou challengeYou are notified of
Lineage and impact evidence → architect, BAAuthoritative source decision ← architect, data ownerA "source" that is really a copySchema changes in a source
Synthetic fixtures → QA engineerTest data needs ← QA engineerAny request for a production sampleNew test slices
Index manifest and build → AI engineer, release managerApproved policy versions ← policy officeA document with no owner or no versionWithdrawn or superseded policies
Quality findings → data ownerQuality thresholds ← data stewardA threshold with no sliceIncidents tagged as data issues
Deletion evidence → records managementRecords schedule, legal holds ← records managementA tool whose default retention differs from the scheduleA legal hold placed or released
Reconciliation results → production support, POMonitoring thresholds ← POA monitor that samples only one channelChannel mismatch alerts

Separation of duties. The engineer who builds a pipeline does not approve its promotion. The steward who writes a quality rule does not accept an exception to it; the data owner does. The agent that drafts a pipeline change never holds rights to merge it or to write to a production index.

9. Evidence and records

Evidence produced or consumedSystem of recordRetention owner
Source register (class, owner, permitted purpose)Data catalogData steward
Lineage record per pipelineData catalog or lineage storeData engineer
Index manifest (document, version, hash, added, removed)Asset catalog and evaluation storeData engineer; retention set by records management
Quality results by sliceData-quality platformData steward
Exception record (accepted gap, compensating control, expiry)Exception registerData owner
Deletion propagation logRecords systemRecords management
Traces of AI-drafted pipeline workTrace store behind the AI gatewayPer the records schedule

10. Skills and learning path

LevelSkillsLabs and practice
FoundationData classification, acceptable use, metadata-only prompting, recognizing a near missWrite the data rules section in L1; scenario check: "a colleague pastes ten account rows to debug a query"
PractitionerProvenance, versioned indexes, synthetic data generation, evaluating generated checks against seeded defectsBuild fixtures for L4; build and version the index in L6
AdvancedPoisoning and injection defenses at ingestion, deletion propagation, embedding change as material change, slice design with the stewardExtend L6 with a withdrawn document and a planted instruction; add a banned-conversion rule for SQL to the L3 CI (continuous integration) check

Stewards and owners need decision literacy more than tooling: practice reading a lineage record and an exception request, and deciding.

11. Measures and incentives

MetricDefinitionAnti-gaming note
Lineage coverageShare of AI-fed datasets with lineage to an authoritative source, verified by the stewardAuto-generated lineage nobody checked does not count
Index freshnessShare of policy changes live in the index within the freshness SLAMeasure from the policy office notice, not from build start
Deletion propagation timeTime from withdrawal or deletion to removal from index, caches and copiesProve it with a seeded document, not by reading config
Worst-slice qualityPass rate of quality rules on the weakest decision-relevant sliceAn average hides the slice that hurts customers
Gaps routed, not repairedShare of quality gaps sent to the data ownerRewarding "zero exceptions" rewards silent repair
Fallback rate (shared with the PO)Share of cutoffs shown with the fallback labelA drop after someone "fills" zones is a red flag, not a win

The balanced metric tree is on measure.

12. Cost, capacity and workforce

ItemWhat to plan for
ComputeEmbedding and re-indexing on every approved policy change; versions kept for reproduction. Cost is tagged per index through the platform's FinOps (financial operations: cost visibility and control) showback
Steward capacityThe bottleneck is rarely the pipeline. It is the steward's time to approve definitions and the owner's time to decide exceptions. Fund it
Skills shiftData engineers add retrieval, evaluation and provenance skills; analytics engineers add AI-specific monitoring metrics

13. Anti-patterns and stop conditions

Anti-pattern or triggerWhy it hurtsWhat to do
AI fills missing valuesA hidden model now drives a customer outcomeStop. Route the gap to the data owner. A deliberate proposal goes through intake as High
Real records "for realism"A prohibited data flowStop. Report the near miss. Use synthetic fixtures
Index built from a shared driveUnknown provenance; easy to poisonStop. Approved sources with owners and versions only
Withdrawn document still retrievableThe assistant cites stale policy with confidenceBlock promotion; fix deletion propagation; add the case to the stale slice
Embedding model or chunking change without re-evaluationA material change shipped as a config tweakStep down; re-run the evaluation; notify AI risk
Source schema changeLineage and contracts silently go staleRe-run impact analysis before the next build
Lineage drawn from memoryEvidence that proves nothingGenerate from code and run metadata; the steward verifies

14. Action kit and 30/60/90

Copy this card for every dataset that will reach a prompt, an index or an evaluation set.

# data-readiness-card.yaml (blank; filled version above)
dataset:
authoritative_source:        # service or system, not a copy
classification:              # per the organization's scheme
permitted_purpose:           # approved by the data owner, with date
minimization:                # fields excluded and why
residency:                   # where it is stored and processed
lineage_record:              # link
freshness_sla:
deletion_propagation:        # mechanism + last test date
quality_rules_by_slice:      # link; steward approved
open_exceptions:             # id, owner, expiry
injection_scan:              # for documents entering an index
steward:
owner:

Questions to ask your enablement lead:

WindowData engineer and analytics engineerSteward and owner
First 30 daysFill the source register for every AI-fed source; write the data rules section of the instructions fileName a steward and owner for each source; confirm permitted purposes
Days 31 to 60Ship synthetic fixtures with a real-value scan; version the first index with a manifestSet quality thresholds per slice; decide open exceptions with expiry dates
Days 61 to 90Prove deletion propagation with a seeded document; publish the ingestion golden path to the templates and catalogReview the first freshness and worst-slice report; agree the periodic review cadence

Related tracks: platform engineer, AI engineer, QA engineer, independent validation, risk and compliance. Controls behind this page: governance first.