Note that this information does not constitute official advice, just outlining experiences people have had. Seek advise from your government or a qualified lawyer if you have any concerns!
International travel comes with some pain points surrounding visas.
If you plan on attending a hackathon in a country where you require a visa (due to your nationality) you need to plan in advance. For example:
- For the UK, it can take 3+ weeks to process a visa application.
- For obtaining a Schengen visa for the EU, it can take 15 days (or longer for certain nationalities) to process your application.
You may also require a letter of invitation from the organisers, which you'll have to contact them for. Smaller events tend to be a bit unsure of how to do this.
Be prepared to provide evidence of being a student, etc.
Some events will ask you to register from a separate batch of tickets or not be willing to provide LOIs.
If you are unsure of the requirements, check with your government's travel advice.
Some countries will consider your visit as a business one. Looking at the rules that apply to attending a conference would likely be what effects hackathon attendees.
You can find information on gov.uk for the types of visas that exist to the United Kingdom.
You probably want a Standard Visitor visa.
The visa requirements for the EU can be found here