Software development kits

Platform SDKs

Also known as: Platform software development kits · Extension SDKs · App development kits

Platform software development kits (platform SDKs) are toolkits that enable developers to build applications, extensions and integrations for a specific platform. They define extension points, provide integration mechanisms and support the creation of software that operates within the ecosystem of a platform. Platform SDKs are central to the growth of digital ecosystems, in which third parties add functionality that the platform provider does not offer itself.

By knowledge.aitechdoc.world · Last reviewed September 29, 2026

Definition

A platform SDK is a collection of tools, libraries and documentation that facilitates the development of software components that extend or integrate with a platform. These components may include plug-ins, modules, applications or automation scripts. Platform SDKs define the rules and interfaces through which external software interacts with the platform: which extension points exist, how an extension declares itself and its required permissions, and how it is packaged, reviewed and distributed.

The term is used in two senses. In a general sense it denotes any kit for extending a software platform, as in this article. Historically, "Platform SDK" was also the proper name of the Microsoft toolkit for Windows development, which was later renamed the Windows SDK.

Historical development

Platform SDKs emerged as software platforms evolved from monolithic systems into extensible ecosystems. Early examples include the plug-in interfaces of desktop applications, the development kits of desktop operating systems and the customization frameworks of enterprise software suites. Web browsers introduced extension models of their own, and mobile operating systems combined SDKs with centralized app stores that review and distribute third-party software.

As software as a service (SaaS) and cloud platforms grew, platform SDKs became essential for enabling third-party integrations and extensions. Because a SaaS platform serves many customers from shared infrastructure, its extension models place particular emphasis on isolation, declared permissions and review processes. Several platforms moved from extensions that run on the customer’s own installation to extensions hosted and sandboxed by the platform itself.

Components

Platform SDKs typically include the following components.

Extension APIs. APIs that define how external software interacts with platform features, such as user interface areas, data objects and events.
Plug-in frameworks. Frameworks that support the creation of modular extensions, including lifecycle hooks, a manifest that describes the extension and packaging tools.
Integration tools. Tools for connecting external systems to platform services, such as webhooks, event subscriptions and connectors.
Authentication mechanisms. Systems for managing identity and access control, typically based on OAuth 2.0 with scopes that limit what an extension may do.
Development and test environments. Local emulators, sandboxed developer instances and command-line tools for building, testing and deploying extensions.
Documentation and specifications. Detailed descriptions of extension points, integration patterns, design guidelines and the rules for publication in a marketplace.

Function and purpose

Platform SDKs serve several functions.

Extensibility. They enable the creation of new functionality within the platform.
Integration. They support connections between the platform and external systems.
Ecosystem growth. They allow third-party developers to contribute to the capabilities of the platform.
Governance. They set the boundaries within which extensions operate, through permissions, sandboxing, review and versioned extension interfaces.

Applications

Platform SDKs are used in enterprise software, cloud platforms, e-commerce systems, collaboration tools and development environments. Examples include the development tools of the Salesforce Platform, the SAP Cloud SDK for extensions on SAP Business Technology Platform, the Atlassian Plugin SDK for self-hosted products and the Forge platform for Atlassian cloud products, the app development tools of Shopify and the extension API of the Visual Studio Code editor. Component content management systems and content delivery platforms likewise offer extension models, for example for custom output formats or integrations with translation systems.

The boundary between platform SDKs and developer SDKs is not sharp. The SAP Cloud SDK, for instance, contains client libraries for SAP APIs as well as tools for building extension applications; many platforms offer both kinds of kit side by side.

Role in digital ecosystems

Digital ecosystems rely on platform SDKs to expand functionality beyond the core features of a platform. SDKs enable the creation of specialized applications that meet diverse user needs, and app marketplaces make these applications available to the platform’s customers. The stability of extension interfaces is a precondition for such ecosystems: changes are commonly announced in advance and older interface versions remain available for a defined period.

Comparison with developer SDKs

Platform SDKs differ from developer SDKs in scope and direction. Developer SDKs expose platform APIs to external applications, which call the platform; platform SDKs define extension mechanisms through which the platform calls or hosts external code. In the first case the external application controls the interaction; in the second, the platform determines when and under what conditions an extension runs. The context card Platform extension points describes the mechanisms involved.

Conclusion

Platform SDKs are essential for building extensible software ecosystems. They provide the tools necessary for creating integrations, plug-ins and applications that operate within the environment of a platform, and they define the rules under which such software is admitted.

Cite this article

knowledge.aitechdoc.world. “Platform SDKs.” Encyclopedia, AI TechDoc Blog. Last reviewed September 29, 2026. https://knowledge.aitechdoc.world/encyclopedia/software-development-kits/platform-sdks

Glossary terms

iiRDS docking point

In iiRDS (intelligent information Request and Delivery Standard), a docking point is an iiRDS class that is meant to be extended with proprietary subclasses and instances, because the resources it describes — such as components, product variants or events — are too company- or industry-specific for the standard to define.

Application programming interface (API)

In software engineering, an application programming interface (API) is a defined set of functions, data structures, messages or endpoints through which one software component offers services to other components, together with the rules for using them. In industrial automation, APIs connect control software, engineering tools, MES, cloud services and custom applications.

API gateway

In software architecture, an API gateway is a service that acts as the single entry point for client requests to a set of backend services, routing each request and typically handling authentication, rate limiting, protocol translation and logging.

Authentication

In industrial cybersecurity, authentication is the verification of the identity of a user, device or system before it is granted access. It answers the question “who is this?”, not “what may they do?”.

Authorization

In industrial cybersecurity, authorization is the determination of which actions an authenticated user, device or system is permitted to perform. It is usually implemented through roles and permissions following the principle of least privilege.

Software framework

In software engineering, a software framework is a reusable software structure that provides generic functionality and a defined control flow, into which developers insert application-specific code at designated extension points.

Middleware

In software engineering, middleware is software that sits between the operating system or network and applications and provides common services such as communication, messaging, data access or security, so applications need not implement them.

Interface contract

In software engineering, an interface contract is the explicit specification of the mutual obligations between a component and its users at an interface, including preconditions the caller must meet, postconditions and guarantees the component provides, invariants, error behavior and timing.

Backward compatibility

In systems engineering, backward compatibility is the controlled ability of a new version to work with older data, interfaces or peer systems. It is a defined and tested property, not an assumption that old inputs will still be handled.

Deprecation path

In systems engineering, a deprecation path is a controlled plan for announcing, replacing, migrating and removing an old version or function. It gives dependents a defined period and a defined route to move away from what is being retired.

Low-code/no-code platform

In software engineering, a low-code/no-code platform is a development environment that lets users build applications largely through graphical configuration, templates and drag-and-drop components, with little or no hand-written code.

Cloud computing

Cloud computing is a model for on-demand network access to a shared pool of configurable computing resources, such as servers, storage, applications and services, that can be provisioned and released rapidly with minimal management effort. Service models include IaaS, PaaS and SaaS; deployment models include public, private, community and hybrid cloud.