In the generation since apartheid ended in 1994, tens of billions of dollars in public funds — intended to develop the economy and improve the lives of black South Africans — have been siphoned off by leaders of the A.N.C., the very organization that had promised them a new, equal and just nation

Corruption has enriched A.N.C. leaders and their business allies — black and white South Africans, as well as foreigners. But the supposed beneficiaries of many government projects, in whose names the money was spent, have been left with little but seething anger and deepening disillusionment with the state of post-apartheid South Africa. While poverty has declined since the end of apartheid, inequality has risen in a society that was already one of the world’s most unequal, according to a recent report by the World Bank and the South African government. South Africa has a large, advanced economy, an aggressively free press and a wealth of independent organizations and scholars who keep a close watch on government malfeasance. But even with its vibrant democracy, in which the details of corruption schemes are routinely aired and condemned by the news media and opposition politicians, graft has engulfed the country. The nation was governed for nine years by the scandal-plagued President Jacob Zuma, whose close ties with the Gupta family — three Indian brothers at the helm of a sprawling business empire built on government contracts, including the dairy farm — outraged voters. Their cozy relationship contributed to the A.N.C.’s recent electoral losses and helped lead to Zuma’s ouster. Promising a “new dawn,” Zuma’s replacement, Cyril Ramaphosa, has said that he would make fighting corruption a priority as the nation’s new president. But he is also a veteran A.N.C. insider, and the early signs have not been encouraging. Having become party leader by a razor-thin margin, Ramaphosa has tried to keep together a fractured A.N.C. by moving cautiously. He formed his first cabinet by appointing some well-respected officials, but also included allies — his own and Zuma’s — who have been accused of corruption by the Public Protector’s office and good governance groups. Beyond that, politicians who long oversaw provinces rife with public corruption now sit at the top of the A.N.C.’s hierarchy. National prosecutors, often criticized for being servile to the sitting president, say that they are trying to recover more than $4 billion lost to corruption related to the Gupta family’s undue influence on Zuma’s administration. And that is just a small measure of the corruption that has whittled away at virtually every institution in the country, including schools, public housing, the police, the power utility, South African Airways and state enterprises overseeing everything from rail service to the defense industry.