Reference
At a glance
Section titled “At a glance”Reference material answers exact questions: which symbol, which value, which support level, which clause. This tab holds the verified surface of NextPDF — module reference, support matrices, the API surface, the error reference, standards conformance, and the policies the project publishes. Reference is not the task-oriented path — when you want to reach a goal rather than look one fact up, use the Guides or the Cookbook.
Reference map
Section titled “Reference map”Core engine
Section titled “Core engine”The nextpdf/core engine, documented one module at a time.
| Page | Use it for |
|---|---|
| Core engine reference | The namespace map: every module page and the four sub-families. |
| Contracts: 41 public interfaces (SPI) | The stability-tracked public interfaces and enums. |
| Core: Document facade + concern traits | The Document facade and the Has* trait family. |
| HTML: HTML+CSS to PDF rendering subsystem | The single-pass streaming HTML renderer. |
| Security: encryption, crypto-policy, and the signing surface | Encryption, permissions, and signing integration points. |
Rendering support
Section titled “Rendering support”What the renderer verifies, claims, partially supports, or does not support.
| Page | Use it for |
|---|---|
| CSS support matrix | Per-feature Cascading Style Sheets (CSS) support levels in the HTML pipeline. |
| Unsupported CSS features and workarounds | What is out of scope and what to do instead. |
| Font and script support matrix | Font technologies and writing-system support. |
| CJK vertical writing support | Vertical writing-mode support for Chinese, Japanese, and Korean text. |
| Complex-script shaping support | Shaping support for scripts that require it. |
API surface
Section titled “API surface”Exact symbols, allowed values, and service contracts.
| Page | Use it for |
|---|---|
| Enum reference | Every public enum and its allowed values. |
| TSA configuration | The default Time-Stamping Authority (TSA) and how to change it. |
| Connect REST API reference | The REST endpoints of NextPDF Connect, from the OpenAPI 3.1 document. |
| Connect API explorer | The interactive explorer for the same contract. |
Package-level Application Programming Interface (API) references live with their packages: Connect API reference, Integrations API index, and Python SDK API reference in the Guides tab.
Error reference
Section titled “Error reference”Every exception the engine raises, by domain, with its structured context and recovery guidance.
| Page | Use it for |
|---|---|
| Error reference | The exception model: the NextPdfException base and the context contract. |
| Core and general errors | Document lifecycle and general engine failures. |
| Rendering and I/O errors | HTML, font, writer, and reader failures. |
| Security and signing errors | Encryption, signing, and PKI failures. |
| Runtime and support errors | HTTP, resilience, and observability failures. |
| Accelerator errors | Failures of the optional acceleration sidecar. |
| Compliance errors | Validation and conformance-tooling failures. |
Standards conformance
Section titled “Standards conformance”The standard profiles NextPDF Core targets, each with its boundary stated: the engine produces output intended to conform; an external validator decides conformance.
| Page | Use it for |
|---|---|
| Standards conformance | The conformance posture and the profile index. |
| PDF 2.0 conformance | The ISO 32000-2 baseline the engine targets. |
| PDF/A-4 conformance | Archival conformance, with its PDF/A-4 clause map. |
| PDF/UA-2 conformance | Accessibility conformance, with its PDF/UA-2 clause map. |
| PDF/X conformance | Print-production conformance. |
| PAdES clause map | The ETSI EN 319 142 baseline-profile mapping for PDF signatures. |
| ZUGFeRD / Factur-X conformance | Hybrid electronic-invoice conformance. |
Trust center
Section titled “Trust center”The engineering posture of the core engine, with the boundary of each claim.
| Page | Use it for |
|---|---|
| Trust center | The posture index. |
| Product licensing | The license terms of the open core and the commercial editions. |
| Trademark and brand use | How the NextPDF name and marks may be used. |
| Data handling, PII, and telemetry | What the engine reads, stores, and transmits. |
| Signature and encryption security model | The cryptographic design and its limits. |
| Engine threat model | What the engine defends against, and what it does not. |
| Vulnerability disclosure policy | How to report a vulnerability. |
Project and releases
Section titled “Project and releases”| Page | Use it for |
|---|---|
| Changelog | What changed in each release. |
| Changelog conventions | How changelog entries are written and classified. |
| Versioning, stability, deprecation, and support policy | The compatibility promises across releases. |
| How NextPDF documentation is structured | The structure and governance of this documentation set. |
Glossary
Section titled “Glossary”Glossary — the terms this documentation uses, defined once for reuse across the documentation.
Reference entry contract
Section titled “Reference entry contract”Every API entry must answer the same questions:
| Question | Required answer |
|---|---|
| What do I call? | Fully qualified symbol, endpoint, command-line interface (CLI) command, or config key. |
| What input is accepted? | Parameter table with type, required status, default, and accepted values. |
| What happens by default? | The behavior when optional input is omitted. |
| What comes back? | Return type, response body, file output, stream, or side effect. |
| What can fail? | Exception, validation error, HTTP status, or operational failure mode. |
| How do I use it safely? | Security, worker-safety, size-limit, path, timeout, and secret-handling notes. |
Coverage policy
Section titled “Coverage policy”API and behavior reference pages are source-backed. Public APIs are documented from package source, config files, tests, and examples. Internal helper classes are documented only when application developers must understand their behavior to configure or operate the package.
Translation readiness
Section titled “Translation readiness”Reference pages prefer tables over dense paragraphs. Each row should stand on its own, because later Extensible Localization Interchange File Format (XLIFF) segmentation will split content by block.