Licensing

Papyra is commercial software with a free Community tier. A valid license key is required to build an application that references Papyra - there is no functional difference between tiers once you’ve built: no feature gates, no output limits, and rendered documents carry no notice of any kind.

Using Papyra commercially above the Community eligibility threshold (see tiers below) without a Professional or Enterprise license is a breach of the license terms in the LICENSE file shipped with the NuGet package.

Set your license key

Embed it at build time via MSBuild:

<PropertyGroup>
  <PapyraLicense>your-license-key</PapyraLicense>
</PropertyGroup>

Alternatively, drop a papyra.lic file containing the key into your project directory or any directory above it (typically the repo root) - the build picks it up automatically. To use a custom location, set the PapyraLicenseFile MSBuild property to the file’s path.

Resolution order: PapyraLicense wins over PapyraLicenseFile, which wins over a discovered papyra.lic.

How keys are verified

A license key is a signed token (ES256 - ECDSA P-256 with SHA-256). Papyra’s license check is entirely a build-time step: the NuGet package’s build integration verifies the token’s signature against its embedded public key, and checks its expiry - entirely offline. Papyra never phones home, and your documents never leave your machine. There is no runtime check of any kind.

A missing, malformed, forged, or expired key is a build error in a Release build - your build does not succeed until a valid key is supplied. In a Debug build (the default $(Configuration) for local development), the same conditions are downgraded to a build warning instead, so your inner loop isn’t blocked by licensing - only dotnet build -c Release / dotnet publish enforce the license:

Code	Meaning
PAPY001	No license key found
PAPY002	License key malformed or unreadable
PAPY003	License key expired
PAPY004	License key signature is invalid (tampered, or not signed by Papyra)

The token’s own header is never trusted to select the algorithm or key, so algorithm-confusion and alg: none tokens simply fail verification.

Tiers

Tier	Who it’s for	Price
Community	Individuals, open source, companies under $1M annual gross revenue	Free - request a key
Evaluation	Any company: evaluation, development, testing, staging - not production	Free - request a key, valid 45 days
Professional	Commercial use with email support	$1,999 / year
Enterprise	Organization-wide use, priority support	$3,999 / year

Professional and Enterprise keys are delivered by email immediately after checkout. Community and Evaluation keys are requested via the self-service form and reviewed manually - expect your key within a day or two. See pricing for a full comparison of what differs between the tiers.

A refund ends the license grant: after a refunded purchase the key must no longer be used, even though it remains cryptographically valid until its expiry date.

When a key expires

Community, Professional, and Enterprise keys are valid for one year; Evaluation keys for 45 days. An expired key is treated like a missing key: your next Release build fails with PAPY003 (a Debug build only warns) until you supply a fresh one. Applications you already built keep running unaffected - there is no runtime check to break them. Renewing your subscription gets you a fresh key by email; Community users simply submit a new request - renewal is free.

CI and build servers

The key is not machine-bound. Use the same key on developer machines and CI - store it as a secret and inject it via the PapyraLicense MSBuild property or an environment-specific configuration. The check runs on every build, and CI pipelines typically build with -c Release (or dotnet publish, which defaults to Release), where a missing or invalid key is a hard error - so CI needs the secret configured to build at all, not just to avoid a warning.