Grainne Walsh, founder of Metalman Brewing. Metalman Brewing Staff at Amazon's Dublin office were treated to a special tipple this year. Locally brewed craft beer was laid on. Not only that, it was actually made by one of their own.

The beer for the tech giant's Irish Christmas party was supplied by Metalman Brewing, a nearby microbrewery founded by former Amazon engineer Grainne Walsh.

"We push our beer a lot in the tech community in Dublin," Walsh told Business Insider.

"We were up at Amazon, we did Airbnb prior to that. We try to ingratiate ourselves in the tech industry. There's usually someone knocking around who I know from my previous life."

Walsh, whose background is in network engineering, worked for Amazon in Ireland from 2007 to 2011, setting up several internal technical teams.

"While I was working in the tech industry, my heart wasn't really in it," she says. "While people would be talking about database front ends at lunch, I would be thinking about beer. That was where my enthusiasm lies. The writing was kind of on the wall for me."

Walsh was already a keen home brewer because she says "it was the only reliable way to get good beer" in Ireland at the time.

"I had gotten quite good at it and youth being a great motivator and optimism, I decided that what I should do is just jack in my job and go and set up a brewery. I don't know if I'd do it now!"

Walsh inspecting one of her brews. Metalman Brewing. How did she cope jumping from a global giant like Amazon to becoming self-employed?

Walsh says: "When there's always someone to buy your printer paper or toilet paper, you kind of forget that you need to do that. Those are the kind of things that shelter you when you work for a big multinational."

But she adds: "I'm a firm believer that whatever you learn in life is going to help you along the line somewhere.

"Really running a small business is all about problem solving — you have X resources and you need to do Y thing. How do you apply those resources in the most efficient way you can and how do you resolve the problems it presents along the way. It's the same really with everything."

She did not leave Amazon totally behind either. "A couple of engineers I used to work with at Amazon helped me out at the start, they put in a temperature monitor system in the brewery," Walsh says. Metalman's brand and cans was also inspired by the art deco stylings Walsh was exposed to in Seattle during regular trips to Amazon's headquarters there. (The name Metalman comes from a nearby local Irish landmark.)

Metalman recently upgraded from a 650-litre brewing kit to one four times the size and last year installed the first canning line in an Irish microbrewery. Walsh plans to start exporting Metalman outside of Ireland for the first time in 2017.

Does she ever miss Amazon? "While I really enjoyed that building process of setting up those teams, I kind of knew I wasn't into the techy side of things as everyone else at Amazon was. It kind of clarified things for me. While I was working in the tech industry, my heart wasn't really in it. And what I really was interested in was beer."