Our Singapore integration methodology connects government platforms, financial systems, and enterprise applications reliably. Integration assessment: mapping all systems that need to connect, their API capabilities (or lack thereof), data flows (what data moves where, how frequently, how critically), and regulatory requirements (MAS TRM for financial data, PDPA for personal data). Each integration point assessed for technical approach (API, file-based, event-driven, RPA), data transformation requirements, error handling needs, and monitoring requirements. Integration architecture: selecting the right pattern for each integration scenario. API gateway: Kong or AWS API Gateway managing all external API connections — centralising authentication, rate limiting, logging, and versioning. Internal APIs also routed through the gateway for consistent management. Event-driven integration: Apache Kafka or AWS EventBridge for real-time data flow between systems — when a customer payment is received, events trigger account update, receipt generation, and accounting entry simultaneously without point-to-point coupling. File-based integration: for systems requiring file exchange (CPF submission files, bank GIRO batch files, some government systems) — automated file generation, secure transfer (SFTP), and processing confirmation. Webhook integration: for SaaS platforms (Salesforce, HubSpot, Xero) that support webhooks — real-time notification of changes enabling immediate downstream processing. Government API implementation: SingPass/MyInfo following the specific technical requirements — PKCE OAuth 2.0 flow, JWE/JWS for data encryption/signing, environment-specific certificates, and careful handling of the consent/data retrieval flow including edge cases (consent declined, partial data availability, session timeout). TradeNet following the specific message formats and submission protocols. IRAS/ACRA following their respective API specifications with appropriate authentication and data formatting. Error handling and reliability: retry logic (transient failures retried with exponential backoff), dead letter queues (failed messages preserved for investigation, not lost), circuit breakers (protecting downstream systems from cascade failures), idempotency (ensuring that retried operations don't create duplicates — critical for financial transactions), and reconciliation (automated comparison between source and target systems verifying data consistency). Monitoring and alerting: real-time dashboards showing integration health — message volumes, success rates, error rates, latency. Critical failures alerting operations within minutes via SMS, WhatsApp, or Slack. Business-level monitoring: not just "is the integration running?" but "did all 2,340 CPF records process correctly this month?"