How Attestly works: A technical overview

Attestly is built around a simple primitive: the presence receipt. A presence receipt is a signed document that attests someone was at a specific place, at a specific time, for a specific purpose. Unlike traditional attendance records that live in organizational databases, presence receipts are portable—owned by the recipient and verifiable by anyone.

The system involves three roles: issuers who create and sign receipts, recipients who claim and hold receipts, and verifiers who check receipt authenticity. Let's walk through each step.

Step 1: Creating a receipt type

Before issuing receipts, an organization defines a receipt type. This is a template that specifies what kind of presence is being documented: volunteer hours, training attendance, site visits, or something custom.

A receipt type includes metadata like the organization name, the purpose category, and any custom fields needed (such as "hours completed" for volunteer work). Once created, the receipt type gets a unique identifier and signing key.

Step 2: Issuing receipts to participants

When someone completes the activity—finishes their volunteer shift, attends a training session, or visits a job site—the issuer generates a receipt. This can happen in several ways:

• QR code scan: Participants scan a code displayed at the location, which triggers receipt generation.
• Direct link: Issuers share a claim link via email or text after verifying attendance.
• Bulk issuance: For events with attendance lists, issuers can generate receipts for multiple recipients at once.

Each receipt contains the participant's identity (verified via email), the receipt type details, a precise timestamp, and the issuer's signature. The signature is computed over all receipt data—change any field and the signature becomes invalid.

Step 3: Verification by third parties

Here's where presence receipts differ fundamentally from attendance records. When a recipient needs to prove their presence—to an employer, a university, a court, or an auditor—they share their receipt link.

The verifier clicks the link and sees the receipt details along with a verification status. Behind the scenes, the system checks that:

• The signature is valid
• The receipt hasn't been modified since issuance
• The issuing organization is legitimate
• The receipt hasn't been revoked

Verification requires no account, no API key, and no relationship with Attestly. Anyone with the link can verify—that's the point. The proof is portable.

Getting started

Organizations can create their first receipt type in under five minutes. Recipients need only an email address. Verifiers need nothing at all—just a link.

The first 50 receipts are free, with no credit card required. For organizations with ongoing verification needs, paid plans start at $49/month.