Mortgage platform with fragmented data systems
MORTGAGE PLATFORM TRANSFORMATION
From Fragmented SQL Systems to a Governed, Scalable Data Foundation
Executive Summary
A mortgage and lending platform operating across fragmented SQL systems transformed its scattered data operations into a governed, scalable data foundation. By implementing a Medallion architecture on Microsoft Fabric, centralizing ingestion pipelines, and connecting Power BI exclusively to a clean business layer, the organization eliminated reporting inconsistencies, reduced manual reconciliation, and gave leadership full confidence in their numbers.
Client Context
Reports differing across teams and analysts
Manual SQL queries rebuilt every reporting cycle
No governed or consistent data layer in place
The business needed a single, trusted data foundation to support reporting, compliance, and growth at scale.
Business Problem
- Operational Challenges
- Reports rebuilt manually for every reporting cycle
- Same report produced different numbers across teams
- Reconciliation done manually across disconnected systems
- Audit requests slow and painful to fulfill accurately
- Technology Gaps
- No governed data layer or consistent business logic
- Transformations duplicated across individual SQL scripts
- BI tools connected directly to raw, untransformed tables
- No data lineage tracking or validation rules in place
- Business Impact
- Leadership lost confidence in reported numbers
- Inconsistent data created risk in financial operations
- Heavy reliance on SQL experts for every data request
- Scaling reporting required rebuilding logic from scratch
Solution Overview
- INGESTION LAYER Centralized Data Pipelines
- Controlled pipelines pulling from loan and servicing systems
- Raw data landed cleanly into centralized environment
- No transformation at ingestion — just clean capture
- Single entry point replacing scattered ad hoc SQL queries
- MEDALLION ARCHITECTURE Bronze, Silver & Gold Layers
- Bronze stores exact, immutable copy of all source data
- Silver standardizes, deduplicates and normalizes records
- Gold defines KPIs, loan metrics and reporting aggregations
- Business logic now lives in one place across all teams
- REPORTING LAYER Power BI on Gold Layer
- Power BI connected exclusively to the Gold data layer
- Metrics predefined and consistent across all departments
- Eliminated duplicate logic and conflicting report outputs
- Dashboards trusted by leadership for financial decisions
- GOVERNANCE LAYER Data Quality & Lineage
- Validation rules embedded across all pipeline stages
- Full data lineage tracked from source to dashboard
- Access controls enforced across all data layers
- Any number on any dashboard fully traceable to source
Architecture Overview
Detailed Execution Flow
1
Data Ingestion
- Data pulled from loan, servicing and external systems
- Raw data landed into centralized lakehouse environment
- Clean capture with no transformation at entry point
2
Bronze Layer
- Exact copy of source data stored immutably
- Audit-friendly and fully traceable to origin
- Foundation for all downstream transformation stages
3
Silver Layer
- Raw data standardized and deduplicated at this stage
- Fields normalized for consistent downstream consumption
- Removes noise while preserving full data fidelity
4
Gold Layer
- Business KPIs and loan metrics defined and locked
- Aggregations built for direct reporting consumption
- Single location for all business logic and definitions
5
Reporting & BI
- Power BI connects exclusively to Gold layer outputs
- Consistent metrics rendered across all departments
- No direct access to raw or silver layers from BI tools
6
Governance & Compliance
- Lineage tracked across all layers end to end
- Validation rules enforce data quality at every stage
- Audit responses delivered faster with full traceability
Technology Stack
Data Platform
Microsoft Fabric
Lakehouse Architecture
Delta Tables
Transformation
PySpark
SQL
Medallion Model
Reporting
Power BI
Predefined Gold Layer Metrics
Role-Based Dashboards
Governance
Data Lineage Tracking
Validation Rules
Access Controls
Key Strategic Decisions
Why Medallion Architecture?
- Raw, clean and business logic clearly separated
- Business definitions locked in Gold layer
- Full auditability from dashboard to source
Why Microsoft Fabric?
- Unified lakehouse for storage & transformation
- Native Power BI, simpler pipelines
- Scales without infrastructure overhead
Why Govern Before Migrating?
- Speed wasn't the issue - trust was
- Business logic first prevents inconsistency
- Shared definitions > raw performance
Scalability & Extensibility
New data sources plug into ingestion layer without rework
Medallion model scales with data volume across loan portfolios
Gold layer metrics extend as new business lines are added
Governance framework adapts to new compliance requirements easily
Business Impact
Data Confidence
- Trusted numbers across leadership
- Single source of truth
Operational Efficiency
- Reconciliation eliminated
- Reports reused, not rebuilt
Compliance Readiness
- Faster audit responses
- Validation at every stage
Scalability
- Scales without analyst dependency
- New metrics added easily
