In the public sector, governments and the people they serve increasingly collaborate to coproduce public services. To support the coproduction of municipal services, specifically, local governments have incorporated various digital technologies into their information systems. How do digital technologies affect community residents' engagement in coproducing municipal services? Our analysis of the service requests submitted to New York City's municipal 311 system shows that both the introduction and use of the NYC311 app were associated with increased request volume in every community, but the app's positive effect on community engagement was weaker for minority communities, especially those with high percentage of black populations at median-low to median-high income levels. These findings help bridge public administration and technology perspectives on community engagement by showing how ethnoracial and socio-economic factors moderate the effectiveness of digital technology. Accordingly, governments are advised to heed these factors when adopting digital technology to support public service coproduction.