Why this matters
As a Data Platform Engineer, you build tools others must trust quickly: ingestion SDKs, pipelines, dbt models, governance workflows. Clear documentation and runnable examples reduce onboarding time, prevent support tickets, and keep teams unblocked during incidents.
- Onboarding: New teams can ship their first pipeline the same day.
- Reliability: Runbooks turn pager events into quick, correct actions.
- Adoption: Good examples demonstrate value and best practices.
Who this is for
- Data Platform Engineers building internal data products and tooling.
- Analytics Engineers documenting dbt models and datasets.
- ML/Data Engineers publishing SDKs, connectors, or Airflow/Flow jobs.
Prerequisites
- Basic Git workflow (branch, commit, PR).
- Comfort with SQL and either Python or your platform’s SDK.
- Understanding of your platform’s deployment and monitoring basics.
Concept explained simply
Documentation answers: What is this? Why use it? How do I start? How do I debug? Reference tells every option. Examples show working patterns to copy.
Mental model
- Layers of docs (think onion):
- Overview: purpose, benefits, scope.
- Quickstart: 5–10 minute path to first success.
- How-to guides: step-by-step for common tasks.
- Reference: exhaustive API/config options.
- Runbook/Troubleshooting: detect, diagnose, resolve.
- Examples are tests you run by hand: self-contained, copy-pastable, with expected output.
- Docs are a product: versioned, reviewed, and owned.
Reusable templates
DocSpec mini-template (fill this for any tool)
- Purpose: what problem it solves, who benefits.
- Prerequisites: accounts, roles, access, versions.
- Quickstart: minimal steps to first success.
- How-to: common tasks (one goal per guide).
- Reference: API/configs/CLI flags with defaults.
- Operations: runbook, SLOs, alerts, dashboards.
- Versioning: current version, breaking changes, migration.
- Ownership: team, contact, review cadence.
ExampleSpec checklist (for runnable examples)
- Single goal, small scope.
- Setup steps with exact commands.
- Copy-paste code plus inline comments.
- Expected output or validation query.
- Cleanup steps to avoid costs/state pollution.
- Runtime note: estimated time and resource needs.
Worked examples
1) Quickstart for an ingestion SDK
Goal: Ingest a CSV into the bronze layer.
- Install:
pip install acme-data-ingest(requires Python 3.10+) - Auth: Set
ACME_TOKENenv var. - Run:
# ingest_csv.py
from acme_ingest import Client
c = Client()
c.ingest_csv(
dataset="sales_bronze",
path="./samples/sales.csv",
delimiter=",",
header=True
)
print("Rows loaded: ", c.last_result.rows)
Expected: console shows row count; table bronze.sales updated.
Cleanup: delete local sample file if created.
2) Minimal pipeline runbook
Scope: Airflow DAG daily_customer_dim
- Normal runtime: 8–12 minutes; SLO: succeeds by 02:00 UTC.
- Critical alerts: task
build_dimfails or SLA miss.
Diagnose
- Check last run logs for
HTTP 429(source throttling). - Run validation query:
select count(*) from dim_customer where load_date = current_date; expect > 0.
Resolve
- If 429: rerun with backfill window of 1 day; increase backoff to 5s.
- If schema drift: apply data contract patch (add nullable column), then rerun.
Owner: Data Platform Team; Review quarterly.
3) Dataset README (copy-ready)
Dataset: analytics.orders_daily
- Business purpose: Orders with daily grain for dashboards.
- Freshness: by 03:00 UTC (90th percentile), alert at 04:00.
- Schema (excerpt):
order_id(PK),customer_id,order_ts,status,total_usd. - Quality checks: not-null
order_id, validstatusin {new, paid, shipped, canceled}. - Backfill policy: up to 30 days.
- Owner: Analytics Engineering.
Example query:
select date(order_ts) as d, sum(total_usd) as revenue
from analytics.orders_daily
where d >= current_date - interval '7 day'
group by 1
order by 1;
Exercises
Do these to lock in the skill. A short checklist is included. Solutions are available, but try first.
Exercise 1: Rewrite a bad doc into a great Quickstart
See Exercises list below (ex1). Aim for a 5–10 minute path to first success.
Exercise 2: Build a runnable example with validation
See Exercises list below (ex2). Include setup, run, expected output, and cleanup.
Self-check checklist
- Purpose is clear in the first 2 sentences.
- Prerequisites are explicit (versions, roles, access).
- Copy-paste commands actually work together in order.
- There is a visible success signal and a way to verify it (query, log line).
- Rollback/cleanup steps are present.
Common mistakes and how to self-check
- Mixing how-to and reference in one page: Separate tasks from exhaustive lists. Self-check: does the page ask the reader to decide among 20 options before starting? If yes, split it.
- No first-run success path: Add a Quickstart that produces a clear visible result. Self-check: can a new user succeed in under 10 minutes?
- Hidden prerequisites: Always list roles, network allowlists, tokens, and versions. Self-check: can you run it fresh in a clean environment?
- Examples that don’t match production constraints: Mirror auth, naming, and resource limits. Self-check: does your sample exceed quotas or skip governance steps?
- Stale docs: Add ownership and review cadence. Self-check: does the page show last reviewed date?
Practical projects
- Create a Quickstart and a runbook for one existing pipeline. Ask a teammate to follow it; capture time-to-first-success.
- Publish two runnable examples: one ingestion, one transformation. Add validation queries and cleanup steps.
- Convert one large doc into four layers: Overview, Quickstart, How-to, Reference.
Learning path
- Draft a DocSpec for one platform component you own.
- Write a Quickstart that runs end-to-end locally or in dev.
- Add two how-to guides for top support tickets.
- Fill in reference options from code/config with defaults.
- Write a runbook with detect-diagnose-resolve and SLOs.
- Publish two runnable examples with validation and cleanup.
Quick test
Everyone can take this quick test; sign in to save your progress.
Next steps
- Adopt the DocSpec and ExampleSpec templates for all new components.
- Set review cadences for critical docs (quarterly at minimum).
- Collect feedback: add a short issue template for doc gaps.
Mini challenge
Pick a confusing internal tool and ship a 1-page Quickstart plus a runnable example that proves a real result (row count, dashboard refresh, or alert cleared). Measure time-to-first-success before and after.