Online staffing firm Freelancer.com reported jobs involving web development rank among the fastest-growing jobs on its platform. For example, the fastest-growing job category listed on the site was ASP, which stands for “active server pages,” with 54.8% growth in jobs, according to Freelancer.com’s quarterly report.

ASP is an older technology usually run on a Microsoft web server that allows web developers to create more dynamic and interactive websites. And the second-fastest growing job category was React.js followed by XML.

Freelancer.com based its report on an analysis of more than 530,000 jobs posted in the second quarter.

It also noted opportunities for customary engineering skills made a surprising jump on the current list with mechanical engineering , engineering and electrical engineering all rounding up the top 50 most sought-after jobs.

“The gig economy has clearly grown in the past decade, this is proven when we see that lawyers, engineers and other highly skilled professionals are not only hiring freelancers, but themselves becoming one,” Freelancer.com Chief Executive Matt Barrie said.

However, the report noted posting of some popular jobs declined. YouTube posted the largest drop in demand, down by 23.1% and only 973 jobs posted. And Bitcoin and Blockchain fell by 22.3% and 9.7% respectively.

“The reasons behind why employers are not posting as many Bitcoin-related jobs could be due to the high volatility in its prices, which might be prompting buyers to take a step back and consider other possible investments,” according to Freelancer.com.

The top-10 fastest-growing jobs of Q2 2018 and the quarter over quarter growth:

• ASP: 54.8%
• React.js: 25.4%
• XML: 23.8%
• Statistical analysis: 23.3%
• Academic writing: 23.1%
• Adobe InDesign: 21.4%
• Mechanical engineering: 18.3%
• Statistics: 18.0%
• Laravel: 17.4
• Algorithm: 15.1%

The jobs with the most contraction over the quarter include:

• YouTube: -23.1%
• Bitcoin: -22.3%
• App developer: -16.3%
• Social networking: -14.4%
• Photography: -12.1%
• CSS3: -10.9%
• Blockchain: -9.7%
• Software development: -8.8%
• Website management: -8.8%
• Prestashop: -8.8%
• Blog install: -8.8%
• Shopping carts: -8.6%