London recently joined 28 other cities to host a Geeklist Hack4Good event, forming part of a growing movement of global 'hackathons'. The events provide people with an opportunity to use their skills in software engineering, design and product development to rapidly build or 'hack' projects for social good.

Despite their growing popularity for Friends of the Earth, and perhaps many other NGOs, the thought of opening up our knottiest problems to an unknown group can still feel scary. Who will be there? What will they expect? What happens if we build something amazing? What if it's not?

In October 2013, we were given the chance to find our own answers by going to our very first hackathon. With just a week to pick a challenge, prepare a pitch and send a team to get a first-hand experience of what was possible, here's what we learned.

Picking a challenge

The best candidates for a hack challenge can be things that you're already grappling with. Projects that got shelved because of a lack of time. Or a tough problem that needs a fresh approach.

For us it was expanding digital tools for our local groups. We wanted to build something, which would empower people in the UK and elsewhere to do long-term, in-depth campaigning. We asked if this could be our hackathon challenge.

Preparing a good pitch

Our challenge for the hackers was pretty broad. We refined a pitch document – not dissimilar to an elevator pitch – that laid out why the problem needs solving, how others had tried to solve it and how technology could help.

The process was iterative and needed to balance differing views on:

• How much detail do you need to define the problem without ruling out any potential solutions.

• Being realistic on what could be achieved without constraining creativity.

By doing this, we gained an in-depth understanding of the challenge ahead of the event.

Forming a team

The strongest pitches cover why the challenge was important, and illustrate potential areas of technical expertise that might provide a breakthrough. The real work starts after the pitches and it is useful to have people on hand to chat through ideas with potential hack team members, bringing together ideas for solutions and getting a sense of what skills people have that could work well for a team. From this fluid discussion, a self-organised team can emerge with between two to five people on the night.

Moulding ideas into action

If a team has come together to work on the problem the first night, the hours that follow will be a crucial period for setting a realistic goal for the build and negotiating its focus.

This part of the hack works best if people from your organisation are on-hand to work alongside the teams. Even with a loose or only partially formed team, hackathon mentors or other product and project specialists can help to outline in a few hours a description of a minimum product you are aiming for. This process also helps to articulate any specific skills that might still be needing in the team, making it easier to make callouts for support from people around the world.

48 hours and beyond

All projects built over the weekend are usually presented on the last day. A judging panel awards prizes and this can range from access to web services to investment to develop projects further, but for NGOs or other projects intended for social good, greater value often is in creating the drive needed to innovate.

Over 48 hours, the team who worked on our challenge built a proof of concept for CauseHub, a platform that would support anyone who cared about a cause by using public data to build possible actions that can contribute towards that cause. They came third, but were so inspired by the project idea that they were accepted into a start-up programme, that invests in building solutions to social and environmental problems.

So why hack?

Hackathons are inherently unpredictable. There are no guarantees, with failure as likely as success. We were lucky enough to have an amazing team and project created out of our first event, but our most recent hackathon failed to bring together a team and a build. This is part of the risk and appeal.

Each event will be a unique mix of people who have chosen to give their time and skills to solve different problems. It means you should be prepared to be surprised and to be challenged. To embrace the possibility of going back to the drawing board, but also the chance of achieving something extraordinary.

Wendy Yuen is the major campaign co-ordinator at Friends of the Earth. Follow @wwwfoecouk on Twitter

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