Before this week, Mohammed al-Bashir was little known outside the areas dominated by HTS in the north-western provinces of Idlib and Aleppo.
According to his CV, he trained as an electrical engineer and worked at gas plants before the start of the civil war in 2011.
In January, Bashir was appointed prime minister of the Salvation Government (SG), which HTS established to run the territory under its control.
The SG functioned like a state, with ministries, local departments, judicial and security authorities, while maintaining a religious council guided by Islamic law.
Around four million people, many of them displaced from elsewhere in the country, lived under its rule.
When institutions stopped functioning in Aleppo after HTS and its allies captured the city earlier this month at the start of their lightning offensive, the SG stepped in to restore public services.
Technicians reportedly helped repair local electricity and telecommunications networks, security forces patrolled streets, medics volunteered at hospitals, and charities distributed bread.
"It is true that Idlib is a small region lacking resources, but they \[SG officials\] have a very high-level of experience after starting with nothing," HTS leader Abu Mohammed al-Jolani was heard telling Assad's former prime minister, Mohammed al-Jalali, in a video of a meeting in Damascus on Monday.
"We will benefit from your experiences. We certainly won't ignore you," he added.
On Tuesday, Bashir was pictured chairing a meeting of former SG ministers and ministers who served under Jalali. He was sat in front of the Syrian opposition and the HTS flags.
"\[We\] invited members from the old government and some directors from the administration in Idlib and its surrounding areas in order to facilitate all the necessary works for the next two months until we have a constitutional system to be able to serve the Syrian people," Bashir told Al Jazeera afterwards.
"We had other meetings to restart the institutions to be able to serve our people in Syria," he added.