We built the ML data platform over 16 weeks. Phase 1 (weeks 1-5): data ingestion layer. We built ingestion connectors for all 8 source systems: Guidewire ClaimCenter and PolicyCenter (CDC — Change Data Capture — for near-real-time claim and policy data), SAP (daily batch extraction for financial data), Salesforce (API-based extraction for broker and relationship data), the legacy reinsurance system (database-direct extraction — the system had no API), and the 3 spreadsheet-based processes (we built a structured data entry interface replacing the spreadsheets — the niche product data now enters the platform directly rather than through uncontrolled Excel files). Data landed in an AWS S3 data lake (Sydney region — ap-southeast-2, satisfying Australian data residency expectations) with raw data preserved in its original format before any transformation. Phase 2 (weeks 4-10): data transformation and quality. dbt transformation layer: 140 dbt models transforming raw source data into analytics-ready datasets.
Key transformations: policy data enrichment (filling the 12% missing industry classification by matching against ABN Lookup and ANZSIC codes — reducing the gap from 12% to 1.4%), claims data normalisation (standardising claim types, causes, and outcomes across the different classifications used by the legacy and current claims systems), exposure calculation (computing earned premium, claim incurred, and loss ratio at policy, product, and portfolio levels — the fundamental metrics for insurance analytics), customer entity resolution (matching broker records across Salesforce and Guidewire — resolving the 15% of broker records that were duplicated across systems), and financial reconciliation (ensuring that data platform financial totals reconcile to SAP general ledger — providing confidence that the data platform is materially accurate).
Data quality monitoring: 320 automated data quality tests running on every pipeline execution: completeness tests (every required field populated), consistency tests (cross-system values match — policy premium in Guidewire matches SAP revenue), range tests (claim amounts, policy periods, and ratios within expected ranges), and freshness tests (data updated within expected timeframes — alerting if a source system stop providing updates). Phase 3 (weeks 8-14): feature store and ML infrastructure. Feature store: Feast deployed on AWS, serving 85 pre-computed features organised into feature groups: policy features (premium, sum insured, policy duration, coverage type, industry classification, geographic risk zone), claims features (claims frequency, severity, loss ratio, average settlement time, litigation rate — computed at policy, product, and portfolio levels), customer features (relationship duration, multi-policy flag, broker relationship, payment history, renewal retention rate), and derived features (risk scores, pricing adequacy indicators, fraud risk indicators — computed from combinations of the base features).
Feature serving: batch features served from the Offline Store (Redshift) for model training, and online features served from the Online Store (DynamoDB) for real-time inference. Training-serving consistency ensured by Feast's architecture — the same feature computation code produces features for both training and serving, preventing training-serving skew. ML experiment tracking: MLflow deployed for experiment tracking, model versioning, and model registry — enabling data scientists to track experiments, compare model performance, and promote models from development to production through a governed process. Phase 4 (weeks 12-16): governance, documentation, and handover. Data lineage: complete lineage documentation showing the path from source system through transformation to feature store — every feature traceable to its source data elements. Data catalogue: all datasets and features documented with: business description, source system, transformation logic, update frequency, data quality metrics, and access controls.
APRA documentation: data governance framework documenting the platform's compliance with CPG 235 — data classification, quality management, access controls, and audit capability. The documentation was prepared for presentation during APRA examinations. Team training: the CDO's data team (2 data engineers, 3 data scientists) trained on: platform architecture, dbt development (adding new transformations), Feast feature management, and MLflow experiment workflow.