[3][4] As a lawyer and member of the Vetëvendosje Movement, Mjeku has been active in strategic litigation against abuses in publicly owned enterprises, environmental protection, and the energy sector.

His mother, Fatime, is a dentist whose private office was used by the dental school of the University of Pristina for several years, as Albanian-language education was suppressed under the Serbian regime.

Mjeku majored in political science with a pre-concentration and minored in Spanish, and graduated magna cum laude with a bachelor of arts degree in May 2010.

During his undergraduate studies, he spent a semester at American University in Washington, DC, and a summer's program at Universidad Nacional in Heredia, Costa Rica.

His opinions were instrumental to recalling major state assets from indolent buyers that failed to comply with their commitments to invest and employ local workers.

[13] After the first Kurti government was sworn in in February 2020, Mjeku served as legal adviser to the minister of economy, employment, trade, industry, entrepreneurship and strategic investments, Rozeta Hajdari.

In July 2020, Mjeku represented the workers union of the Kosovo Telecom in an attempt to undo an unfavorable revenue-share contract with a virtual mobile operator.

In December 2020, Mjeku then served as the attorney for Vetëvendosje activists seeking a restraining order on three hydropower plants due to concerns of environmental degradation.

Key legislative proposals include a new law on investments, fuel market, foreign trade, competition, inspections, intellectual property and price control.

[15][1] On 1 September 2022, he was transferred as deputy minister to the Ministry of Economy, which is in charge of energy, mines, ICT, and publicly owned enterprises.

[1][16] Mjeku primarily supervised state-owned enterprises, which include the nation's largest energy and mining operators, the postal office, the leading telecom provider, railways, and water utility and irrigation companies.

He co-lead the working group that drafted the Law on the Sovereign Fund of the Republic of Kosova, a strategic wealth management and investments entity, hailed as a transformation reform for Kosovo's economy.

He has adopted techniques taught by his professor Bryan Garner to Kosovar legislation and court documents,[8] even drafting a proposed constitution for Kosovo to showcase his style.