--- title: "1.10 release notes" canonical_url: "https://www.nutrient.io/guides/document-engine/release-notes/1-10/" md_url: "https://www.nutrient.io/guides/document-engine/release-notes/1-10.md" last_updated: "2026-05-20T19:49:34.771Z" description: "Latest updates and release notes for Nutrient Document Engine SDK, including new features, improvements, and bug fixes." --- Before attempting to upgrade to Document Engine 1.10, make sure your application runs as expected on your current version. If you’re on version 1.6.1 or later, you can upgrade directly to 1.10. If you’re on an earlier version, follow the step-by-step upgrade path outlined in our [upgrade](https://www.nutrient.io/guides/document-engine/release-notes/upgrading.md#general-advice) guide. ## Regression We found that versions 1.10.0 and 1.10.1 stop handling the `DATABASE_CONNECTIONS` environment variable correctly, and it defaults to `10` instead of `20`. If you need to configure the number of database connections, set the `PGPOOL_SIZE` variable instead. This workaround is only valid for 1.10.x, and you should revert back to `DATABASE_CONNECTIONS` in the upcoming 1.11.0 release. ## Highlights ### GdPicture update This version ships with [GdPicture 14.3.9](https://www.nutrient.io/guides/dotnet/changelog.md#14.3.9). This is an upgrade that mainly brings fixes to Microsoft Office documents. ### Build instructions This version adds new options to the `applyXfdfAction` when importing XFDF files to documents using the `.../build` instructions. Specifically, these options are now available: - `ignorePageRotation` — This determines if page rotation will be ignored when applying XFDF files. - `richTextEnabled` — This determines if text annotations from the XFDF files should be converted to rich or plain text. #### Convert documents to HTML and Markdown This version can now convert PDF documents into structured HTML or Markdown formats. This new feature is designed to accurately preserve a document’s layout and formatting, including text, headings, tables, and styles. To use it, set the output type to `html` or `markdown` in your `.../build` instructions. Note that this requires an HTML or Markdown conversion license. #### PDF/UA accessibility auto-tagging You can now automatically tag your PDF documents, ensuring they’re compliant with the PDF/UA-1 standard. This makes your documents screen reader-ready and accessible to a wider audience. To enable this, specify the output type as `pdfua` in your `.../build` instructions. Note that this requires the PDF/UA accessibility auto-tagging license. For implementation details and examples, refer to the [PDF/UA conversion guide](https://www.nutrient.io/guides/document-engine/conversion/to-pdfua.md). #### Affected endpoints All endpoints that work with `.../build` instructions are affected by this change, including: - `/api/documents/{documentId}/apply_instructions` - `/api/documents/{documentId}/layers/{layerName}/apply_instructions` - `/api/build` Refer to the Document Engine [API reference](https://www.nutrient.io/api/reference/document-engine/upstream/) for more information. ### Prometheus exporter release notes The Prometheus exporter provides HTTP endpoints for exposing application metrics in a format compatible with Prometheus. This enables easy integration with Prometheus for monitoring and alerting. #### Features - Exposes metrics via an HTTP server. - Configurable port for the metrics endpoint. - Ability to enable or disable the exporter via application configuration. - Supports setting global labels for all exported metrics. #### Configuration - `ENABLE_PROMETHEUS` — Set to `true` to enable Prometheus (defaults to `false`). - `PROMETHEUS_PORT` — Port number for the Prometheus metrics HTTP server (defaults to `9091`). - `PROMETHEUS_GLOBAL_LABELS` — Comma-separated list of global labels for all metrics (e.g. `env=prod,app=api`). - `METRICS_CUSTOM_TAGS` — Comma-separated list of global tags (e.g. `region=us-east,version=1.0`). The `METRICS_CUSTOM_TAGS` environment variable can be used to set custom tags for the metrics. It’s meant to be a global setting that applies to **all metric exporters**, and not only the Prometheus exporter. ### Server response header By default, Document Engine replies with the following header: ```http server: Document Engine/1.10.0 ``` You can now control it via the new `SERVER_HEADER_TOKENS` environment variable. Supported values are: - `off` — No `server` header in response - `name` — `server: Document Engine` header in response - `version` — `server: Document Engine/1.10.0` header in response If the value isn’t provided, or if an invalid value is provided, Document Engine defaults to `version` with an appropriate warning in logs. ### Hoard (internal cache) Our system uses an internal cache called Hoard to store frequently accessed data, particularly large files or parts of them. Sometimes, a small piece of data we want to cache might internally reference a much larger file. To prevent the cache from unnecessarily holding on to that entire large file, Hoard can intelligently copy just the relevant small piece, optimizing memory usage. This release introduces two new environment variables. - `HOARD_MAX_SIZE` — Defaults to `100000000` bytes (100 MB). Represents the maximum Hoard cache size. - `HOARD_BINARY_COPY_ENABLED` — Enabled by default. To disable, set the value to `off`, `no`, `false`, or `0`. - `HOARD_BINARY_COPY_THRESHOLD` — Default value is `2`; can be set to any integer value. The `HOARD_BINARY_COPY_ENABLED` and `HOARD_BINARY_COPY_THRESHOLD` environment variables give advanced users control over this specific memory optimization. `HOARD_BINARY_COPY_ENABLED` toggles this copying feature, while `HOARD_BINARY_COPY_THRESHOLD` sets the size ratio at which a copy is performed. These are highly technical settings with carefully optimized default values. We strongly advise against changing them unless you have a deep understanding of our system’s memory management, as incorrect configurations can significantly impact memory usage and overall performance. ## Breaking changes ### Minimize information disclosure option removed The undocumented `MINIMIZE_INFORMATION_DISCLOSURE` environment variable is no longer supported. It was removed in favor of the new `SERVER_HEADER_TOKENS` environment variable. To migrate to this new variable, replace `MINIMIZE_INFORMATION_DISCLOSURE=true` with `SERVER_HEADER_TOKENS=off`. ## Database migrations This release doesn’t include any database migration. ## Changelog A full list of changes, along with the issue numbers, is available [here](https://www.nutrient.io/guides/document-engine/changelog.md#1.10.0). --- ## Related pages - [1 1](/guides/document-engine/release-notes/1-1.md) - [1 11](/guides/document-engine/release-notes/1-11.md) - [1 12](/guides/document-engine/release-notes/1-12.md) - [1 13](/guides/document-engine/release-notes/1-13.md) - [1 14](/guides/document-engine/release-notes/1-14.md) - [1 2](/guides/document-engine/release-notes/1-2.md) - [1 4](/guides/document-engine/release-notes/1-4.md) - [1 15](/guides/document-engine/release-notes/1-15.md) - [1 3](/guides/document-engine/release-notes/1-3.md) - [1 5](/guides/document-engine/release-notes/1-5.md) - [1 7](/guides/document-engine/release-notes/1-7.md) - [1 6](/guides/document-engine/release-notes/1-6.md) - [1 9](/guides/document-engine/release-notes/1-9.md) - [1 8](/guides/document-engine/release-notes/1-8.md) - [Upgrading from PSPDFKit Processor](/guides/document-engine/release-notes/upgrading-from-processor.md) - [Upgrading from PSPDFKit Server](/guides/document-engine/release-notes/upgrading-from-server.md) - [Upgrading Document Engine](/guides/document-engine/release-notes/upgrading.md)