I’ve spent the better part of two decades inventorying public APIs across the U.S. federal government, and the catalog has grown to a point where it deserves its own roundup. What follows is the current state of that catalog: every federal agency I’m tracking that exposes some kind of public-facing API, RSS feed, open-data surface, or referenced internal system, indexed in machine-readable form as APIs.yml in a dedicated GitHub repository under github.com/api-evangelist. Each entry below links to that repository so you can pull the structured index, the controlled vocabulary, and where applicable the OpenAPI specs. There are 211 agencies in this snapshot, ranging from cabinet departments down through bureaus, independent commissions, inspectors general, and the research labs and museums that quietly publish some of the most useful data in Washington. The list is alphabetical, not hierarchical — the federal org chart is a fiction APIs don’t respect anyway. If an agency is missing or an API has moved, the issues queue on each repo is the right place to flag it. Administration for Community Living (ACL) Repository: https://github.com/api-evangelist/administration-for-community-living-acl- The Administration for Community Living (ACL) is part of the United States Department of Health and Human Services. ACL works to maximize the independence, well-being, and health of older adults, people with disabilities across the lifespan, and their families and caregivers. The agency administers the Older Americans Act programs, supports disability services through centers for independent living, and maintains the AGing, Independence, and Disability (AGID) Program Data Portal providing publicly accessible datasets on aging and disability programs. ACL also operates the National Institute on Disability, Independent Living and Rehabilitation Research (NIDILRR). APIs and surfaces: AGID Program Data Portal — The AGing, Independence, and Disability (AGID) Program Data Portal provides publicly accessible data from programs funded under the Older Americans Act and related disability programs. Datasets include the American Co… Administration for Native Americans (ANA) Repository: https://github.com/api-evangelist/administration-for-native-americans-ana- The Administration for Native Americans (ANA) is an agency within the Administration for Children and Families (ACF), U.S. Department of Health and Human Services. ANA promotes self-sufficiency and cultural preservation for Native Americans, Alaska Natives, Native Hawaiians, and other Pacific Islander communities by providing social and economic development opportunities through financial assistance, training, and technical assistance. ANA administers a $45 million discretionary grant program in three primary areas: Social and Economic Development Strategies (SEDS), Native Language Preservation and Maintenance, and Environmental Regulatory Enhancement. ANA data on funded projects is publicly available through data.gov and healthdata.gov. APIs and surfaces: ANA Projects Report Dataset — The ANA Projects Report dataset provides results and impact analysis for ANA-funded projects in Native American communities. Available through the data.gov and healthdata.gov catalogs, the dataset includes project sum… Administrative Conference of the United States Repository: https://github.com/api-evangelist/administrative-conference-of-the-united-states The Administrative Conference of the United States (ACUS) is an independent federal agency within the executive branch whose statutory mission is to identify ways to improve the procedures by which federal agencies administer regulatory, benefit, and other government programs. ACUS issues approximately a dozen recommendations per…