Getting libnghttp2 on Linux

Delphi-nghttp2 loads libnghttp2.so.14 at startup via dlopen — the shared library must be on the dynamic linker's search path.

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Install from the system package manager (recommended)

Debian / Ubuntu / Raspberry Pi OS

sudo apt install libnghttp2-14

The -dev package (libnghttp2-dev) adds headers and the unversioned .so symlink — needed only if you are building nghttp2-based C code yourself. For running a Delphi-compiled binary, the -14 runtime package is all you need.

Verify the installed version:

dpkg -l libnghttp2-14

Fedora / RHEL / CentOS Stream

sudo dnf install libnghttp2

Arch Linux

sudo pacman -S libnghttp2

openSUSE

sudo zypper install libnghttp2-14

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Verify the library is loadable

ldconfig -p | grep nghttp2

Expected output:

libnghttp2.so.14 (libc6,x86-64) => /usr/lib/x86_64-linux-gnu/libnghttp2.so.14

If it doesn't appear, run sudo ldconfig after installation to update the linker cache.

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Run without installing (LD_LIBRARY_PATH)

If you can't install system-wide (shared hosting, CI container, cross-compile target), download the package and extract the .so:

apt-get download libnghttp2-14
dpkg -x libnghttp2-14_*.deb /tmp/nghttp2-extract
export LD_LIBRARY_PATH=/tmp/nghttp2-extract/usr/lib/x86_64-linux-gnu:$LD_LIBRARY_PATH

Or build from source and install to a local prefix (see Build from source below).

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Build from source

Use this when you need a version newer than what the distro ships, or for cross-compilation targets.

Prerequisites: GCC or Clang, CMake ≥ 3.25, pkg-config.

git clone https://github.com/nghttp2/nghttp2.git
cd nghttp2

cmake -S . -B build \
  -DCMAKE_BUILD_TYPE=Release  \
  -DENABLE_LIB_ONLY=ON        \
  -DENABLE_SHARED=ON          \
  -DENABLE_STATIC=OFF         \
  -DENABLE_EXAMPLES=OFF       \
  -DENABLE_APP=OFF            \
  -DENABLE_TESTS=OFF          \
  -DCMAKE_INSTALL_PREFIX=/usr/local

cmake --build build --target nghttp2
sudo cmake --install build
sudo ldconfig

Verify:

ldconfig -p | grep nghttp2
# → libnghttp2.so.14 => /usr/local/lib/libnghttp2.so.14

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ARM / cross-compile targets

The SONAME is libnghttp2.so.14 on all Linux targets (x86_64, ARM64, ARMv7). Install the ARM package on the target board:

sudo apt install libnghttp2-14        # Raspberry Pi OS / Ubuntu ARM

For Delphi Linux64 cross-compilation (PAServer on ARM): install on the physical ARM board, deploy the binary from Windows via PAServer, and run on the board — the loader finds the ARM system library automatically.

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Also needed: OpenSSL (TLS mode only)

TTlsServerContext / TTlsClientContext load libssl.so.3 and libcrypto.so.3 (OpenSSL 3.x). These are almost always already installed on modern Linux distributions.

sudo apt install libssl3          # Debian / Ubuntu
sudo dnf install openssl-libs     # Fedora / RHEL

Verify:

ldconfig -p | grep -E "libssl|libcrypto"

For h2c (cleartext) operation only libnghttp2.so.14 is required.