HeartMuLa is a groundbreaking family of open-source Music Foundation Models designed to deliver commercial-grade music understanding and generation. Developed to bridge the gap between proprietary AI and the open community, HeartMuLa enables creators to generate high-fidelity, long-form music (up to 6 minutes) from text prompts and custom lyrics. Key components include HeartCodec for superior audio compression, HeartTranscriptor for precise lyric recognition, and a 3B/7B parameter LLM backbone that supports multi-lingual generation (English, Chinese, Japanese, Korean, Spanish, etc.). Licensed under Apache 2.0, HeartMuLa offers fine-grained control over song structure (Intro, Verse, Chorus) and style, making it the premier choice for indie filmmakers, content creators, and developers seeking a powerful, localizable, and transparent AI music solution.