Evaldo Rui started out in radio in the '30s with his brother Haroldo Barbosa. His first job was at Rádio Philips, as assistant in the shows Casé and Horas do Outro Mundo, soon becoming a sports commentator. He also worked at the radio stations Educadora, Guanabara, Nacional, Cajuti, and finally Mauá, where he was artistic director. Rui also worked in television for TV Tupi and TV Record. In 1943 he began a partnership with Custódio Mesquita, with whom he would write about 20 romantic songs. The first one was the bolero-canção "Pra Que Viver" (1943). Among the most successful were: "Promessa," "Como os Rios Que Correm Para o Mar," and "Valsa do Meu Subúrbio" (1943), all recorded by Sílvio Caldas; "Rosa de Maio" and "Gira, Gira, Gira" (1944), recorded by Carlos Galhardo; "Valsinha do Turi-Turé," recorded by Linda Batista, and "Feitiçaria," recorded by Sílvio Caldas, both in 1945; "Noturno em Tempo de Samba," and others. After Mesquita's death, Araci de Almeida recorded "Saia do Meu Caminho" in 1946; Linda Batista recorded "Viva o Samba" in 1947; and Dircinha Batista recorded "Adeus" in 1949. In 1950, his samba "Nega Maluca" (with Haroldo Lobo) was a big Carnival hit, performed by Linda Batista.