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Challenge 27

The n8n Murder Mystery

A prototype vanished from a hackathon store room. Use the badge logThe record a door system keeps of who went through which door, in which direction, at what time., the parking records and four witness statements to find who took it.

AdvancedComplexity:Time: 30–45 min

Your task

Something went missing at a Lisbon hackathon. Use the witness statements, the door-badge logThe record a door system keeps of who went through which door, in which direction, at what time. and the parking records to work out who took it, and have your workflow name a single person.

Your bonus task

Prove you are right without anyone telling you the answer: hashA fingerprint of a piece of text. The same text always gives the same fingerprint, but the fingerprint cannot be turned back into the text. the name you found and compare it with the fingerprint printed below.

Example use cases

  • A puzzle evening at a hackathon, where the prize is bragging rights.
  • Anyone learning to join data sets that share one field and nothing else.
  • Any real investigation that works the same way – which account, which shipment, which build broke it.

Before you start

  1. 01

    Sign up for n8n Cloud or open your n8n workspace. No other account is needed.

  2. 02

    Three case files, all invented for this challenge: the badge log and the parking records as CSV, and the people and witness statements as JSON.

  3. 03

    Read the four statements before you build anything. They tell you the time window, the lanyard colour and the car – the three filters you are about to write.

  4. 04

    For the bonus, the SHA-256 fingerprint of the culprit's name in lower case is 7dbf8936cee769e6cec4d1e6a32dd64a164c184b49d301876a3b124b53e7059e. Hash your answer and compare.

What the workflow must do

  1. 01

    The workflow ends with exactly one person, found from the data rather than typed in by hand.

  2. 02

    Each step rules people out for a stated reason: two people were in the store room during the window, only one of those wears a yellow lanyard, and that person's car left the car park minutes later.

  3. 03

    Someone who was in the store room earlier that evening, before the rig went missing, is not accused. Bonus: hashing the name gives exactly the fingerprint printed above.

Solution

See the workflow challenge answer

Reveal the completed workflow only when you are ready to compare it with your own.

Submit as solved

Ready to submit?

Submit when your team has a working workflow to demonstrate.

Solution

Reveal the workflow solution?

This will show the completed workflow for this challenge. Are you sure you want to continue?

Mentor review

Find a mentor and ask them to review.

Show them your working workflow. Once they approve it, collect the balloon for this challenge.

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