pgmem for Python
A real PostgreSQL 18 that runs entirely in memory, packaged as a single binary and driven from Python. Prepare the schema once, then give every test its own fork of that state in about 20 ms.
import pgmem, psycopg
with pgmem.start(database="app") as pg:
with psycopg.connect(pg.template.dsn) as conn:
conn.execute(open("schema.sql").read())
snap = pg.template.snapshot()
with snap.fork() as fork: # private copy of the prepared database
psycopg.connect(fork.dsn) ...
pytest
The wheel registers a plugin. Override pgmem_snapshot to run migrations,
then use pgmem_dsn (or pgmem_fork) in tests:
# conftest.py
@pytest.fixture(scope="session")
def pgmem_snapshot(pgmem_server):
run_migrations(pgmem_server.dsn)
return pgmem_server.snapshot()
# test_orders.py
def test_orders(pgmem_dsn):
with psycopg.connect(pgmem_dsn) as conn: ...
pgmem_class_dsn shares one fork across a test class for read-only tests.
pgmem_options returns the keyword arguments passed to pgmem.start.
Any driver works (psycopg, asyncpg, pg8000, SQLAlchemy): the wrapper only hands out DSNs. The server is one PostgreSQL session per fork; pooled connections are serialized at transaction boundaries.
Binary
Platform wheels bundle the pgmem binary. PGMEM_BINARY overrides the
lookup for platforms without a wheel or for local builds
(go build ./cmd/pgmem).
1 maintainer
Release files for pgmem 0.19.0
For a detailed explanation of source distributions (sdists) and built distributions (wheels), please see the package formats documentation.
Built distributions (wheels)
| File | Reset | |||
|---|---|---|---|---|
| pgmem-0.19.0-py3-none-win_arm64.whl | Python 3 | none | Windows ARM64 | Details |
| pgmem-0.19.0-py3-none-win_amd64.whl | Python 3 | none | Windows x86-64 | Details |
| pgmem-0.19.0-py3-none-manylinux_2_17_x86_64.manylinux2014_x86_64.musllinux_1_1_x86_64.whl | Python 3 | none | Linux musl 1.1+ x86-64, Linux glibc 2.17+ x86-64 | Details |
| pgmem-0.19.0-py3-none-manylinux_2_17_aarch64.manylinux2014_aarch64.musllinux_1_1_aarch64.whl | Python 3 | none | Linux glibc 2.17+ ARM64, Linux musl 1.1+ ARM64 | Details |
| pgmem-0.19.0-py3-none-macosx_13_0_arm64.whl | Python 3 | none | macOS 13.0+ ARM64 | Details |
Total release size: 87.0 MB
Release files / pgmem-0.19.0-py3-none-win_arm64.whl
| Download URL | pgmem-0.19.0-py3-none-win_arm64.whl |
|---|---|
| Size | 16.8 MB |
| Tags | Python 3 Windows ARM64 |
|
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| Download URL | pgmem-0.19.0-py3-none-win_amd64.whl |
|---|---|
| Size | 18.2 MB |
| Tags | Python 3 Windows x86-64 |
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twine/7.0.0 CPython/3.13.14
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Transparency logRelease files / pgmem-0.19.0-py3-none-manylinux_2_17_x86_64.manylinux2014_x86_64.musllinux_1_1_x86_64.whl
| Download URL | pgmem-0.19.0-py3-none-manylinux_2_17_x86_64.manylinux2014_x86_64.musllinux_1_1_x86_64.whl |
|---|---|
| Size | 18.1 MB |
| Tags | Linux glibc 2.17+ x86-64 Linux musl 1.1+ x86-64 Python 3 |
|
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| Size | 16.8 MB |
| Tags | Linux glibc 2.17+ ARM64 Linux musl 1.1+ ARM64 Python 3 |
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| Download URL | pgmem-0.19.0-py3-none-macosx_13_0_arm64.whl |
|---|---|
| Size | 17.1 MB |
| Tags | Python 3 macOS 13.0+ ARM64 |
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