diff --git a/.travis.yml b/.travis.yml
index 997945b5..3a889845 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -8,11 +8,10 @@ services:
     - docker
 
 install:
-    - ./mk_dockerfile.sh
-    - docker-compose build
+    - docker build --build-arg PG_VERSION="${PG_VERSION}" --build-arg PYTHON_VERSION="${PYTHON_VERSION}" -t tests -f Dockerfile--${TEST_PLATFORM}.tmpl .
 
 script:
-    - docker-compose run $(bash <(curl -s https://codecov.io/env)) tests
+    - docker run $(bash <(curl -s https://codecov.io/env)) -t tests
 
 notifications:
     email:
@@ -27,5 +26,5 @@ env:
     - TEST_PLATFORM=std PYTHON_VERSION=3 PG_VERSION=12
     - TEST_PLATFORM=std PYTHON_VERSION=3 PG_VERSION=11
     - TEST_PLATFORM=std PYTHON_VERSION=3 PG_VERSION=10
-    - TEST_PLATFORM=std.all PYTHON_VERSION=3 PG_VERSION=17
-    - TEST_PLATFORM=ubuntu-24_04 PYTHON_VERSION=3 PG_VERSION=17
+    - TEST_PLATFORM=std-all PYTHON_VERSION=3 PG_VERSION=17
+    - TEST_PLATFORM=ubuntu_24_04 PYTHON_VERSION=3 PG_VERSION=17
diff --git a/Dockerfile--std.all.tmpl b/Dockerfile--std-all.tmpl
similarity index 60%
rename from Dockerfile--std.all.tmpl
rename to Dockerfile--std-all.tmpl
index dfd9ab20..c41c5a06 100644
--- a/Dockerfile--std.all.tmpl
+++ b/Dockerfile--std-all.tmpl
@@ -1,14 +1,21 @@
-FROM postgres:${PG_VERSION}-alpine
-
-ENV PYTHON=python${PYTHON_VERSION}
-RUN if [ "${PYTHON_VERSION}" = "2" ] ; then \
-	apk add --no-cache curl python2 python2-dev build-base musl-dev \
-    linux-headers py-virtualenv py-pip; \
-	fi
-RUN if [ "${PYTHON_VERSION}" = "3" ] ; then \
-	apk add --no-cache curl python3 python3-dev build-base musl-dev \
-    linux-headers py-virtualenv; \
-	fi
+ARG PG_VERSION
+ARG PYTHON_VERSION 
+
+# --------------------------------------------- base1
+FROM postgres:${PG_VERSION}-alpine as base1
+
+# --------------------------------------------- base2_with_python-2
+FROM base1 as base2_with_python-2
+RUN apk add --no-cache curl python2 python2-dev build-base musl-dev linux-headers py-virtualenv py-pip
+ENV PYTHON_VERSION=2
+
+# --------------------------------------------- base2_with_python-3
+FROM base1 as base2_with_python-3
+RUN apk add --no-cache curl python3 python3-dev build-base musl-dev linux-headers py-virtualenv
+ENV PYTHON_VERSION=3
+
+# --------------------------------------------- final
+FROM base2_with_python-${PYTHON_VERSION} as final
 
 #RUN apk add --no-cache mc
 
@@ -57,4 +64,4 @@ ls -la ~/.ssh/; \
 sudo /usr/sbin/sshd; \
 ssh-keyscan -H localhost >> ~/.ssh/known_hosts; \
 ssh-keyscan -H 127.0.0.1 >> ~/.ssh/known_hosts; \
-TEST_FILTER=\"\" PYTHON_VERSION=${PYTHON_VERSION} bash run_tests.sh;"
+TEST_FILTER=\"\" bash run_tests.sh;"
diff --git a/Dockerfile--std.tmpl b/Dockerfile--std.tmpl
index d844c9a3..91886ede 100644
--- a/Dockerfile--std.tmpl
+++ b/Dockerfile--std.tmpl
@@ -1,14 +1,22 @@
-FROM postgres:${PG_VERSION}-alpine
+ARG PG_VERSION
+ARG PYTHON_VERSION 
+
+# --------------------------------------------- base1
+FROM postgres:${PG_VERSION}-alpine as base1
+
+# --------------------------------------------- base2_with_python-2
+FROM base1 as base2_with_python-2
+RUN apk add --no-cache curl python2 python2-dev build-base musl-dev linux-headers py-virtualenv py-pip
+ENV PYTHON_VERSION=2
+
+# --------------------------------------------- base2_with_python-3
+FROM base1 as base2_with_python-3
+RUN apk add --no-cache curl python3 python3-dev build-base musl-dev linux-headers py-virtualenv
+ENV PYTHON_VERSION=3
+
+# --------------------------------------------- final
+FROM base2_with_python-${PYTHON_VERSION} as final
 
-ENV PYTHON=python${PYTHON_VERSION}
-RUN if [ "${PYTHON_VERSION}" = "2" ] ; then \
-	apk add --no-cache curl python2 python2-dev build-base musl-dev \
-    linux-headers py-virtualenv py-pip; \
-	fi
-RUN if [ "${PYTHON_VERSION}" = "3" ] ; then \
-	apk add --no-cache curl python3 python3-dev build-base musl-dev \
-    linux-headers py-virtualenv; \
-	fi
 ENV LANG=C.UTF-8
 
 ADD . /pg/testgres
@@ -16,4 +24,4 @@ WORKDIR /pg/testgres
 RUN chown -R postgres:postgres /pg
 
 USER postgres
-ENTRYPOINT PYTHON_VERSION=${PYTHON_VERSION} bash run_tests.sh
+ENTRYPOINT bash run_tests.sh
diff --git a/Dockerfile--ubuntu-24_04.tmpl b/Dockerfile--ubuntu_24_04.tmpl
similarity index 71%
rename from Dockerfile--ubuntu-24_04.tmpl
rename to Dockerfile--ubuntu_24_04.tmpl
index fd1136d8..c1ddeab6 100644
--- a/Dockerfile--ubuntu-24_04.tmpl
+++ b/Dockerfile--ubuntu_24_04.tmpl
@@ -1,7 +1,17 @@
-FROM ubuntu:24.04
+ARG PG_VERSION
+ARG PYTHON_VERSION 
+
+# --------------------------------------------- base1
+FROM ubuntu:24.04 as base1
+ARG PG_VERSION
+
+RUN apt update
+RUN apt install -y sudo curl ca-certificates
+RUN apt update
+RUN apt install -y openssh-server
 
 RUN apt update
-RUN apt install -y sudo curl ca-certificates postgresql-common
+RUN apt install -y postgresql-common
 
 RUN bash /usr/share/postgresql-common/pgdg/apt.postgresql.org.sh -y
 
@@ -14,21 +24,12 @@ RUN curl -o /usr/share/postgresql-common/pgdg/apt.postgresql.org.asc --fail http
 RUN apt update
 RUN apt install -y postgresql-${PG_VERSION}
 
-RUN apt install -y python3 python3-dev python3-virtualenv
 # RUN apt install -y mc
 
-# It is required for psycopg2
-RUN apt install -y libpq-dev
-RUN apt install -y openssh-server
-
 # [2025-02-26] It adds the user 'postgres' in the group 'sudo'
 # [2025-02-27] It is not required.
 # RUN adduser postgres sudo
 
-ADD . /pg/testgres
-WORKDIR /pg/testgres
-RUN chown -R postgres /pg
-
 EXPOSE 22
 
 RUN ssh-keygen -A
@@ -36,13 +37,25 @@ RUN ssh-keygen -A
 # It enables execution of "sudo service ssh start" without password
 RUN sh -c "echo postgres ALL=NOPASSWD:/usr/sbin/service ssh start" >> /etc/sudoers
 
-USER postgres
+# --------------------------------------------- base2_with_python-3
+FROM base1 as base2_with_python-3
+RUN apt install -y python3 python3-dev python3-virtualenv libpq-dev
+ENV PYTHON_VERSION=3
+
+# --------------------------------------------- final
+FROM base2_with_python-${PYTHON_VERSION} as final
+
+ADD . /pg/testgres
+WORKDIR /pg/testgres
+RUN chown -R postgres /pg
+
 ENV LANG=C.UTF-8
 
+USER postgres
+
 RUN chmod 700 ~/
 RUN mkdir -p ~/.ssh
 
-#ENTRYPOINT PYTHON_VERSION=3.12 /run.sh
 ENTRYPOINT sh -c " \
 #set -eux; \
 echo HELLO FROM ENTRYPOINT; \
@@ -55,4 +68,4 @@ ssh-keygen -t rsa -f ~/.ssh/id_rsa -q -N ''; \
 cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys; \
 chmod 600 ~/.ssh/authorized_keys; \
 ls -la ~/.ssh/; \
-TEST_FILTER=\"\" PYTHON_VERSION=${PYTHON_VERSION} bash run_tests.sh;"
+TEST_FILTER=\"\" bash ./run_tests.sh;"
diff --git a/docker-compose.yml b/docker-compose.yml
deleted file mode 100644
index 86edf9a4..00000000
--- a/docker-compose.yml
+++ /dev/null
@@ -1,4 +0,0 @@
-version: '3.8'
-services:
-  tests:
-    build: .
diff --git a/mk_dockerfile.sh b/mk_dockerfile.sh
deleted file mode 100755
index 8f7876a3..00000000
--- a/mk_dockerfile.sh
+++ /dev/null
@@ -1,2 +0,0 @@
-set -eu
-sed -e 's/${PYTHON_VERSION}/'${PYTHON_VERSION}/g -e 's/${PG_VERSION}/'${PG_VERSION}/g Dockerfile--${TEST_PLATFORM}.tmpl > Dockerfile