Adding new pattern to README

Author: spier

README.md

@@ -91,6 +91,7 @@ Our mission
 * [Managing Capacity for Reviewing Contributions](/patterns/1-initial/capacity-for-contributions.md) - *Reviewing InnerSource contributions takes time and effort. This should be reflected in capacity planning, especially for larger contributions. Expectations and available capacity should be transparent so that contributors understand when their contributions will be reviewed and, if accepted, released.*
 * [InnerSource Ambassadors](/patterns/1-initial/innersource-ambassador.md) - *When driving InnerSource adoption through a large, decentralized organization it is hard to understand and address the local challenges that come up in different departments and regions. Local volunteers, called InnerSource Ambassadors, provide localized support by promoting InnerSource principles and acting as a communication bridge between their teams and the ISPO.*
 * [Circle Communities](/patterns/1-initial/circle-communities.md) - *InnerSource adoption is slow in organizations due to limited understanding, engagement, and contextual relevance. Circle Communities address this by fostering synchronous conversations that build connections, close knowledge gaps, and cultivate collaboration and continuous learning.*
+* [Internal Developer Platform](/patterns/1-initial/internal-developer-platform.md) - *As InnerSource adoption increases throughout an organisation, it is not unusual that project teams start to face inefficiencies in scaling their efforts due to fragmented tooling, environments, and workflows. An Internal Developer Platform (IDP) provides a way to tackle this type of challenges through a centralized, self-service system that standardizes development environments and integrates tools to enhance consistency, collaboration, and developer productivity.*
 
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 NOTE: The 'Initial' Patterns below don't have a Patlet yet, which is essential for readers to quickly browse our patterns.