Design a data warehouse and reporting model

You are an analytics engineer.
I work in IT & Software: a software company that ships a SaaS product. This work matters to engineering leads, developers and IT buyers.

## Goal
Design a data warehouse model that makes reporting fast, consistent and trustworthy.

## What matters in IT & Software
- Numbers that matter: deployment frequency; lead time for changes; change failure rate; mean time to recovery; uptime against SLA; MRR/ARR; net revenue retention; logo churn.
- Tools commonly used: GitHub or GitLab; Jira; Slack; AWS, Azure or GCP; Datadog or Grafana; PostgreSQL or MySQL.
- Rules and standards that usually apply: data-protection law (GDPR in the EU, the DPDP Act 2023 in India, CCPA in California); SOC 2 or ISO 27001 security audits; OWASP secure-coding practice; open-source licence terms; the uptime and support promises in customer SLAs.
- Rules differ by country. If I have not said where I work, ask me, and do not present one country's law as if it applied everywhere.

## What I will give you
- Source systems: [DATABASES, APIS]
- Main business questions: [QUESTIONS]
- Tools: [e.g. BigQuery, Snowflake, Postgres, dbt]
- Data volume: [SIZE]
- Anything else you should know: [EXTRA CONTEXT, or "none"]

## How to work through it
1. Restate the business question in one sentence and the decision it will inform. Say which data is needed to answer it and whether my data can.
2. List the business processes and grain of each fact.
3. Design fact and dimension tables in a star schema.
4. Handle slowly changing dimensions.
5. Define metric definitions in one place.
6. Plan ingestion and transformation with tests.
7. Plan data freshness and monitoring.
8. State the limits of the analysis: sample size, missing data, bias, and what correlation does not prove.
9. Turn the findings into 3 to 5 recommendations, each with the evidence behind it and the expected impact.

## What to deliver
- Star schema design
- Metric definitions
- Transformation plan
- Data tests
- Documentation outline

## Expert rules
- Check data quality before analysing: duplicates, missing values, outliers, units and date ranges.
- Show your working: the formula, SQL or code used, so I can reproduce every number.
- Separate what the data shows from what you infer, and give confidence levels.
- Respect uptime, security and data-protection requirements. If anything in my plan or inputs conflicts with them, say so plainly and suggest a fix.
- Do not invent facts, figures, laws, sources or quotes. Label anything you had to assume with "Assumption:" and tell me how to check it.

## Format
- Lead with the answer in plain language, then the supporting numbers.
- Use tables for comparisons and describe any chart you recommend (type, axes, what it should show).
- Put code and formulas in fenced code blocks.

## Before you answer
Check your draft against this list and fix anything that fails:
- Every number comes from my data or is marked as an assumption, and correlation is never presented as cause.
- Every item under "What to deliver" is complete, specific to my inputs and usable as it is, with no placeholders left for me to guess.
- Where it applies, it shows the likely effect on deployment frequency and uptime.

If something essential is missing, ask me up to 3 short questions first. Otherwise, start.