Packages¶

For a Postgres you already run on Linux. Each release publishes a .deb, an .rpm and a tarball per Postgres major and architecture, on the releases page. No toolchain, no rebuild.

Prefer a package to the tarball where you can. It can be removed again, and it refuses to install on a system whose glibc is too old, instead of letting you find out when Postgres will not restart. Compatibility lists what is tested.

1. Install the files¶

Debian, UbuntuRHEL, Rocky, Alma 9Tarball

V=0.2.0; PG=17
BASE=https://github.com/dhilipkumars/axiom/releases/download/v$V
ARCH=$(dpkg --print-architecture)
curl -fsSLO "$BASE/postgresql-$PG-axiom_$V-1_$ARCH.deb"
sudo apt install "./postgresql-$PG-axiom_$V-1_$ARCH.deb"

Installs under /usr/lib/postgresql/$PG, beside the server package from the distribution or PGDG, without owning those directories.

V=0.2.0; PG=17
BASE=https://github.com/dhilipkumars/axiom/releases/download/v$V
curl -fsSLO "$BASE/axiom_$PG-$V-1.el9.$(uname -m).rpm"
sudo dnf install "./axiom_$PG-$V-1.el9.$(uname -m).rpm"

Built for PGDG's Postgres (postgresql$PG-server, under /usr/pgsql-$PG), so enable PGDG's repository first. The distribution's own Postgres module is not supported.

V=0.2.0; PG=17; ARCH=$(uname -m | sed -e s/x86_64/amd64/ -e s/aarch64/arm64/)
BASE=https://github.com/dhilipkumars/axiom/releases/download/v$V
curl -fsSLO "$BASE/axiom-$V-pg$PG-linux-$ARCH.tar.gz"
curl -fsSLO "$BASE/axiom-$V-pg$PG-linux-$ARCH.tar.gz.sha256"
sha256sum -c "axiom-$V-pg$PG-linux-$ARCH.tar.gz.sha256"
tar -xzf "axiom-$V-pg$PG-linux-$ARCH.tar.gz"

It holds axiom.so and the extension's control and SQL files, under the paths a Debian-packaged Postgres uses:

sudo cp -r axiom-$V-pg$PG-linux-$ARCH/usr/. /usr/

For any other layout, place the two pieces where pg_config says:

sudo cp axiom-$V-pg$PG-linux-$ARCH/usr/lib/postgresql/$PG/lib/axiom.so \
  "$(pg_config --pkglibdir)/"
sudo cp axiom-$V-pg$PG-linux-$ARCH/usr/share/postgresql/$PG/extension/axiom* \
  "$(pg_config --sharedir)/extension/"

Match the major exactly. A pg17 build is compiled against Postgres 17's headers and does not work with any other major.

2. Preload it, and restart¶

No package can do this part for you. Axiom keeps a cache in shared memory and runs a background worker, both of which exist only if the library loads at startup, so CREATE EXTENSION fails outright without it.

# postgresql.conf -- append to any existing list rather than replacing it
shared_preload_libraries = 'axiom'

Append, don't overwrite. The setting is one comma-separated list, so write 'pg_stat_statements,axiom' if something is already there. Replacing it silently disables whatever was loaded before, at the next restart.

Then restart Postgres. Two more settings are fixed at startup and worth knowing:

Setting	Default	What it does
`axiom.cache_size_mb`	`256`	Upper bound of the shared-memory cache for watch-backed tables.
`axiom.notify_database`	`postgres`	Database the worker sends `NOTIFY axiom_events` in.

3. Give Postgres the gateway's CA¶

Copy the gateway's ca.crt to the database host, somewhere the user Postgres runs as can read. Its path is what the ca_cert option takes. Skip this if the gateway's certificate is signed by a CA the host already trusts.

Next: initialize.