Application architecture Application architecture practices must evolve significantly for the successful implementation of the GC Enterprise Ecosystem Target Architecture. Transitioning from legacy systems based on monolithic architectures to architectures that oriented around business services and based on re‑useable components implementing business capabilities, is a major shift. Interoperability becomes a key element, and the number of stakeholders that must be considered increases. Use open source solutions hosted in public cloud select existing solutions that can be reused over custom built How to achieve: * Summarize how the architecture leverages and reuses existing solutions, components, and processes including: * Existing processes being reused or leveraged; * Existing solutions being reused or leverage, and; * Existing components being reused or leveraged. Tools: * Target State Architecture * Interim State Architecture * EA Assessment contribute all improvements back to the communities How to achieve: * Summarize how the team will align to the TBS Guidance on Open Source Publishing to support the production of better solutions * Summarize how the team will leverage/has leverage the Open Source community Tools: * Target State Architecture * Interim State Architecture register open source software to the Open Resource Exchange How to achieve: * Summarize how the architecture will leverage the Open Resource Exchange. * Summarize how the architecture will utilize APIs to support Open Data feeds Tools: * Target State Architecture * Interim State Architecture Use software as a service (SaaS) hosted in public cloud choose SaaS that best fit for purpose based on alignment with SaaS capabilities How to achieve: * Summarize how the recommended SaaS is the best fit for purpose based on alignment with SaaS capabilities of SaaS provider and Dept/SSC Tools: * Option analysis choose a SaaS solution that is extendable How to achieve: * Summarize how the recommended SaaS is extendable Tools: * Option analysis * EA Assessment configure SaaS and if customization is necessary extend as open source modules How to achieve: * Summarize how the recommended SaaS can be customized through Open Source modules. Tools: * Option analysis * EA Assessment Design for Interoperability design systems as highly modular and loosely coupled services How to achieve: * Summarize how the architecture supports the implementation through: * Simple independent functions * Highly modular * Loosely coupled * Deployed into a container that has just a single application with the ability to build the smallest image Tools: * Target State Architecture * Interim State Architecture expose services, including existing ones, through APIs How to achieve: * Summarize how the architecture exposes functionality as services and these services are accessible through common methodologies * Summarize how the architectures aligns to the Government of Canada Standards on APIs Tools: * Target State Architecture * Interim State Architecture make the APIs discoverable to the appropriate stakeholders How to achieve: * Summarize which APIs will be published to the ESDC API store * Summarize which APIs will be published to the GC API store * Summarize the rational for not publishing APIs to an API store Tools: * Target State Architecture * Interim State Architecture Design for Interoperability, Proposed amendment Jan 8, 2021 design systems as highly modular and loosely coupled services How to achieve: * make all services available through a well-defined interface, such as an application programming interface (API) How to achieve: * all APIs with potential for cross-departmental, inter-jurisdictional, or public consumption must be published to the GC API Store How to achieve: * use the Canadian Digital Exchange Platform (CDXP) for data exchange where suitable (e.g., GC Event Broker for asynchronous messaging)