"How socialist" is a difficult metric against which to measure political developments, but I'll do my best! But it would be prudent, perhaps, to take a step back and better contextualize the question of socialism in Africa.

Ideas surrounding the notion of 'African socialism,' as distinguished from classical socialism, emerged in the early 1950s, amidst the renewed hope of national self-determination in the post-war climate and ahead of the largest surge of African acts of independence in 1958 to 1962.

While preparing the Arusha Declaration and still synthesizing his new political philosophy of Ujamaa, Nyerere once said...

“We, in Africa, have no more need of being 'converted' to socialism than we have of being 'taught' democracy. Both are rooted in our past -- in the traditional society which produced us."

There are many incarnations of African socialism, from Nkrumah's pan-African socialism to Tombalbaye's socialist progressivism, and they all viewed socialism as a natural, upscaled outgrowth of traditional African social conventions.

Take, for example, Nyerere's approach to "social ownership of agriculture," a staple component of classical socialism. In Ujamaa: Essays on Socialism (1968), he wrote...

“In socialist Tanzania, our agricultural organization would be predominantly that of co-operative living and working for the good of all. This means that most of our farming would be done by groups of people who live as a community and work as a community. A nation of such village communities would be a socialist nation”

This approach was actually quite central to the political philosophy of Ujamaa, which had naturally been tailored to its conditions in Tanzania. Nyerere posited that the country was too sparsely populated and so he engineered planned settlements with complete access to free education, clinics, extended water and electricity supplies. Members of these settlements participated in collective farming endeavors on crops that were determined by the government, as well.

In his seminal 1982 Centre for Housing Studies assessment of those same policies, Satiel Kulaba wrote...

"Compared to her level of development, and being a poor country with very limited resources, Tanzania has made considerable achievements in providing community facilities and social services--especially clean, piped rural water supply, health services schools and rural roads."

Mind you, while President Nyerere was an ambitious social engineer, the country remained a democracy throughout its post-independence history. This means social control was limited and most socialist components of governance were limited, particularly in Arusha and Dar es Salaam. The fact that Nyerere stepped down after his legally-mandated terms in office were complete assured the longevity of his social programs.

I've visited Tanzania and Zanzibar many times and the achievements of Nyerere's socialism--ambitious in scale, more modest in implementation--are well understood and appreciated there. In most restaurants in Tanzania, you will still see a portrait of President Nyerere hanging on the walls.

I hope I've answered your question!

I would typically hyperlink to Wikipedia and other useful resources for further reading... but the mods don't like that ;(