VellumPdf.Conformance 2.0.0

.NET 10.0 This package targets .NET 10.0. The package is compatible with this framework or higher. 
dotnet add package VellumPdf.Conformance --version 2.0.0
                    


                    

                
NuGet\Install-Package VellumPdf.Conformance -Version 2.0.0
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package. 
<PackageReference Include="VellumPdf.Conformance" Version="2.0.0" />
For projects that support PackageReference, copy this XML node into the project file to reference the package. 
<PackageVersion Include="VellumPdf.Conformance" Version="2.0.0" />
                    


                            Directory.Packages.props
                        

                    

                
<PackageReference Include="VellumPdf.Conformance" />
                    


                            Project file
For projects that support Central Package Management (CPM), copy this XML node into the solution Directory.Packages.props file to version the package. 
paket add VellumPdf.Conformance --version 2.0.0
                    


                    

                
#r "nuget: VellumPdf.Conformance, 2.0.0"
#r directive can be used in F# Interactive and Polyglot Notebooks. Copy this into the interactive tool or source code of the script to reference the package. 
#:package VellumPdf.Conformance@2.0.0
#:package directive can be used in C# file-based apps starting in .NET 10 preview 4. Copy this into a .cs file before any lines of code to reference the package. 
#addin nuget:?package=VellumPdf.Conformance&version=2.0.0
                    


                            Install as a Cake Addin
                        

                    

                
#tool nuget:?package=VellumPdf.Conformance&version=2.0.0
                    


                            Install as a Cake Tool

VellumPdf.Conformance

NuGet CI

In-process PDF/A and PDF/UA preflight validation for VellumPdf, a dependency-free PDF library for .NET 10. It opens a PDF through VellumPdf.Reader and runs a registry of clean-room conformance rules authored from the ISO specifications, with no external veraPDF Docker image required.

  • Validates PDF/A-2b/2u/2a and PDF/UA-1.
  • Returns machine-readable assertions: rule id, ISO clause, severity, and object reference.
  • BCL-only, AOT- and trim-ready — rules are registered explicitly, with no reflection.
  • Build-verified veraPDF parity is about 99%; every rule's positive and negative paths are cross-checked against veraPDF in CI.

Stable as of 2.0. The public API is locked and analyzer-enforced. Rule coverage is still growing: veraPDF parity is about 99%, and the remaining gaps are tracked as issues rather than hidden behind a preview label.

Install

dotnet add package VellumPdf.Conformance

Usage

using VellumPdf.Conformance;

var result = PdfPreflight.Validate(File.OpenRead("input.pdf"), PdfConformance.PdfA2B);

if (!result.IsCompliant)
    foreach (var assertion in result.Assertions)
        Console.WriteLine($"{assertion.Severity} {assertion.RuleId} ({assertion.Clause}): {assertion.Message}");

For a ready-made command-line validator, install VellumPdf.Cli (vellum-preflight).

Documentation

Architecture and validator scope: https://github.com/Tim81/VellumPDF/blob/main/docs/architecture.md

The VellumPdf family

Package Status Summary
VellumPdf.Kernel Stable Low-level PDF object model, canvas, fonts, images, encryption.
VellumPdf.Fonts.Standard14 Stable Embeddable standard-14 font substitutes for PDF/A text.
VellumPdf.Layout Stable High-level document builder: paragraphs, tables, images, pagination.
VellumPdf.Signing Stable PAdES / PKCS#7 digital signatures with timestamps and LTV.
VellumPdf.Reader Preview Opens existing PDFs; exposes catalog, signatures, and streams.
VellumPdf.Conformance (this package) Stable In-process PDF/A and PDF/UA preflight validation.
VellumPdf.Cli Stable vellum-preflight command-line PDF/A and PDF/UA validator.
VellumPdf.Barcodes Stable QR, Data Matrix, Aztec, PDF417, Code 128/GS1-128, Code 39, EAN/UPC, and ITF-14 as vectors.

Roadmap

Milestone Scope
2.0 — Breaking changes (this release) Strong-named assemblies (#53), an async I/O surface for Save/Sign/loaders (#54), and an external-signer API for cloud KMS and remote HSM signing (#165). Each changes assembly identity or the public contract, so they waited for a major version.
2.1 — PDF reader (structural) VellumPdf.Reader grows classic and cross-reference-stream parsing, object streams, and encryption support, with a fixture corpus proving it against real-world files (Epic #100).
2.2 — PDF content extraction Text and image extraction on top of the reader.
3.0 — Read-modify-write A unified round-trip document model that supersedes the write-once PdfDocument, so existing PDFs can be opened, edited, and saved back (Epic #101).

License

Apache-2.0. Source and issues: https://github.com/Tim81/VellumPDF

Product Compatible and additional computed target framework versions.
.NET net10.0 is compatible.  net10.0-android was computed.  net10.0-browser was computed.  net10.0-ios was computed.  net10.0-maccatalyst was computed.  net10.0-macos was computed.  net10.0-tvos was computed.  net10.0-windows was computed. 
Compatible target framework(s)
Included target framework(s) (in package)
Learn more about Target Frameworks and .NET Standard.

NuGet packages

This package is not used by any NuGet packages.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last Updated
2.0.0 91 8/17/2026
1.11.0 119 7/11/2026
1.10.0 1,286 7/7/2026
1.9.0 611 7/6/2026
1.8.2 105 7/5/2026
1.8.1 131 7/3/2026
1.8.0 109 7/3/2026
1.7.8 104 7/3/2026
1.7.7 111 7/2/2026
1.7.6 114 6/28/2026
1.7.5 122 6/23/2026
1.7.4 112 6/23/2026
1.7.3 120 6/22/2026
1.7.2 129 6/22/2026
1.7.1 116 6/21/2026
1.7.0 120 6/21/2026

See https://github.com/Tim81/VellumPDF/blob/main/CHANGELOG.md for release notes.