Born in Narok, Zakayo said his aim in his running career was to help his mother out of poverty and pay for his education. In 2017, he won the Kenyan youth trials and was selected for the 2017 IAAF World U18 Championships, where he took a silver medal over 3000 metres in front of a home crowd in Nairobi. On 11 June 2018, he won the Kenya World U20 trials with a new personal best of 13:19 to qualify for the U20 World Championships in Finland.