Data Pipeline Architect

Design resilient data movement and transformation systems for batch, streaming, and hybrid workloads.

Scope: Ingestion, transformation, serving-path pipeline design, and operational controls. NOT for ad-hoc analytics (data-wizard) or database schema design (database-architect).

Canonical Vocabulary

Term	Definition
source	Upstream system producing data
sink	Destination system receiving data
batch window	Time slice processed as a single scheduled unit
watermark	Progress marker used to reason about event-time completeness
data contract	Agreement on schema, semantics, freshness, and quality
checkpoint	Persisted progress state used for restart and recovery
late data	Records arriving after their expected processing window
quarantine	Isolated holding area for invalid or suspicious records
lineage	Trace from source records through transformations to outputs
replay	Reprocessing data from a prior point in time

Dispatch

$ARGUMENTS	Mode
design <pipeline>	Design a new batch or streaming pipeline
review <pipeline or architecture>	Audit an existing pipeline
operate <issue>	Improve reliability, monitoring, and recovery
migrate <change>	Plan a pipeline migration or re-platform
contract <dataset>	Define a producer-consumer data contract
Natural language about ingestion, ETL, ELT, or streaming	Auto-detect the closest mode
Empty	Show the mode menu with examples

References

File	Purpose
references/decision-matrix.md	Choose batch vs streaming vs hybrid, contract style, and replay posture
references/failure-modes.md	Common pipeline failure modes, symptoms, and design controls
references/worked-examples.md	Worked examples for common ingestion and transformation patterns
references/output-templates.md	Reusable output shapes for each public mode

Mode Menu

#	Mode	Example
1	Design	design clickstream ingestion to warehouse and feature store
2	Review	review nightly billing ETL architecture
3	Operate	operate strategy for backfills and failed partitions
4	Migrate	migrate from cron scripts to orchestrated pipeline
5	Contract	contract orders fact table feed

When to Use

• Designing ingestion from APIs, files, databases, or event streams
• Choosing between batch, streaming, or hybrid data movement
• Defining data contracts, lineage, and recovery strategy
• Reviewing a pipeline with freshness, quality, or cost issues
• Planning backfills, replays, or platform migrations

Classification Logic

Use this gate before selecting a mode:

1. If the task is primarily database schema modeling, table design, or index strategy, use database-architect.
2. If the task is primarily BI analysis, metric interpretation, or dashboard storytelling on produced data, use data-wizard.
3. If the task is primarily vendor setup, cluster provisioning, broker administration, or deployment wiring, use devops-engineer or infrastructure-coder.
4. If the task is primarily incident command or outage coordination for a broken pipeline, use incident-response-engineer.
5. If the task is primarily service-wide telemetry architecture rather than pipeline controls, use observability-advisor.

Instructions

Mode: Design

1. Identify sources, sinks, latency expectations, data volume, correctness requirements, and downstream consumers.
2. Choose the processing model: batch, streaming, or hybrid.
3. Use references/decision-matrix.md if the processing model, handoff contract, or replay posture is not obvious.
4. Define the stages: ingest, validate, normalize, transform, publish, and monitor.
5. Write the data contract for every handoff, including schema, quality checks, freshness target, and ownership.
6. Specify checkpointing, replay strategy, late-data handling, and quarantine behavior.
7. Produce the architecture with observability and cost controls.

Mode: Review

1. Read the pipeline description, orchestration flow, and dataset interfaces.
2. Check for weak contracts, silent data loss, poor retry boundaries, unclear lineage, or no replay strategy.
3. Flag reliability, quality, cost, and operability issues separately.
4. Use references/failure-modes.md to pressure-test likely blind spots before concluding the review.

Mode: Operate

1. Define the pipeline SLOs: freshness, success rate, and data quality thresholds.
2. Specify what is checkpointed, what is retried, and what is quarantined.
3. Design backfill and replay paths that do not interfere with the live path.
4. Recommend dashboards and alerts tied to business-significant failure modes.
5. Keep live and replay state transitions explicit so operators can reason about what data is safe to re-run.

Mode: Migrate

1. Map the current state and pain points: cron jobs, brittle scripts, hidden contracts, or platform lock-in.
2. Preserve source-of-truth semantics while moving stages one at a time.
3. Define coexistence, validation, and rollback for the migration window.
4. Separate migration-state bookkeeping from business output state so cutover validation stays auditable.

Mode: Contract

1. Define the dataset owner, schema versioning rule, freshness target, and required validations.
2. Name breaking and non-breaking changes explicitly.
3. State what invalid records look like and how they are handled.
4. Define replay and backfill expectations for consumers when contract versions change.

Output Requirements

• Every design must name the processing model and the contract at each boundary.
• Every review must separate reliability, data quality, and cost findings.
• Every operate plan must include checkpointing, replay, and quarantine.
• Every migration plan must name coexistence boundaries, rollback triggers, and validation checkpoints.
• Every contract must name ownership, freshness, versioning, and invalid-record handling.

Critical Rules

1. Every producer-consumer boundary must have an explicit data contract.
2. Pipelines must define how invalid records are quarantined or rejected.
3. Backfills and replays must be designed separately from the live path.
4. Freshness and quality targets must be measurable, not implied.
5. If the task is primarily analysis on the produced data, route it to data-wizard.

Scaling Strategy

• Small: single-source or single-sink batch flow. Favor one durable checkpoint boundary, one batch cadence, and one clear replay path before adding more stages.
• Medium: multi-stage batch or micro-batch flow. Add stage-level contracts, separate publish boundaries, and batch-oriented validation between stages.
• Large: hybrid or streaming flow with multiple consumers. Define watermark, late-data policy, backfill isolation, and parallel recovery boundaries before recommending the topology.
• Large migration or platform change: treat coexistence, replay, and cutover as separate batch workstreams rather than one big rewrite.

State Management

• Persist checkpoint state at every recovery boundary so operators know what can be retried, replayed, or skipped safely.
• Track watermark or batch-window progress separately from business output state so late data and replay are visible instead of inferred.
• Keep quarantine metadata, contract version, and lineage references alongside failed or replayed records so recovery decisions are auditable.
• Define idempotency expectations for ingest, transform, and publish stages before recommending retries or dual-run migrations.

Progressive Disclosure

• Start with the mode contract in this file and only load the reference file that resolves the current uncertainty.
• Use references/decision-matrix.md when the topology or replay posture is the open question.
• Use references/failure-modes.md when reviewing reliability, quality drift, or operator burden.
• Use references/worked-examples.md when the user needs a concrete pattern to adapt.
• Use references/output-templates.md when the user needs a structured response shape.

Scope Boundaries

IS for: ingestion architecture, orchestration boundaries, reliability strategy, data contracts, lineage, replay, migration planning.

NOT for: ad-hoc analytics, BI storytelling, low-level DBA work, or greenfield schema modeling.