(Watch the RECORDING.) Diamond Open Access journals are a vital part of scholarly communication but they often lack the technical capacity to meet visibility standards set by major aggregators, indexes, and funders. With limited staff and budgets, many editorial teams face systemic barriers to interoperability, discoverability, and compliance with open science policies. The EU-funded CRAFT-OA project aims to address this by strengthening the most widely used open-source journal software in the Diamond ecosystem: Open Journal Systems (OJS). Our team at Masaryk University Press contributes to CRAFT-OA as both developers and end users—drawing on over a decade of experience running the MUNI Journals platform (https://journals.muni.cz/), which now supports 48 Diamond OA journals across disciplines and offers full editorial support, integration with global databases, stable hosting, and custom development. This practical environment has proven invaluable for testing new tools and co-designing improvements with real-world users. We are now helping develop and pilot the following OJS innovations within CRAFT-OA: OJS Core Enhancements (GDPR compliance features; Multilingual metadata improvements; Metadata quality tools) and OJS Diamond Plugins (OpenAIRE Graph Connector; EOSC Interoperability Toolkit; OpenAIRE Broker Plugin; Discoverability Companion plugin; JATS/TEI Interoperability plugins). All tools are developed according to FAIR principles, aiming to make Diamond journals not only free to read and publish in, but also visible, reusable, and robustly networked in the open science ecosystem. Our role ensures these developments are both technically sound and practical for real editors, based on continuous feedback from the MUNI Journals community. By aligning open infrastructure with the daily realities of under-resourced journals, we aim to repair a critical gap: the technical invisibility of high-quality, community-led scholarly publishing. The result is a more equitable, sustainable, and interconnected research infrastructure—one that recognizes the full value of Diamond OA.