His parents were Matías Armas, a port worker of socialist extraction, and Nicanda Lago Méndez, a housewife.

[2] He studied teaching and worked for 30 years as a teacher of primary education, until he retired with the position of school director.

[3] The 2009 film El novio de la muerta is based on two of his plays: Sus ojos se cerraron (1992) and Mujeres solas.

[4] Armas has produced and directed adaptations of texts by authors such as Prosper Mérimée, Saint-Exupéry, and Henry Miller.

[1] He has won numerous prizes, such as the 1993 Florencio Award [es] for best national author text for Se ruega no enviar coronas, the 2006 Silver Morosoli Award [es] for career achievement,[4] first prize in the unpublished theater-drama category of the Ministry of Education and Culture's 2011 Annual Literature Prizes for Ave Mater,[5] the 2015 Florencio for 50-year career and in the comedy category for Sus ojos se cerraron,[6] and the 2015 Golden Candelabrum Award [es] from the Uruguayan branch of B'nai B'rith.