diff --git a/Dockerfile b/Dockerfile
index 11e7bf5..d3e2b87 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -21,7 +21,9 @@ RUN chmod +x /usr/local/bin/install-php-extensions
 # PEAR < 1.10.18 can't read pecl.php.net responses anymore.
 RUN pear upgrade --force https://pear.php.net/get/PEAR-1.10.18.tgz
 
-RUN DEBIAN_FRONTEND=noninteractive apt-get update -q \
+# retry: PECL sometimes replies "No releases available" on CI runners.
+RUN retry() { for i in 1 2 3; do "$@" && return; sleep 10; done; return 1; }; \
+    DEBIAN_FRONTEND=noninteractive apt-get update -q \
     && DEBIAN_FRONTEND=noninteractive apt-get install -qq -y \
       curl \
       git \
@@ -60,10 +62,10 @@ RUN DEBIAN_FRONTEND=noninteractive apt-get update -q \
     # other extensions. Installing amqp on its own so that install-php-extensions
     # purges libssl1.0-dev before libssl-dev is installed for the rest.
     && if [ "${PHP_VERSION%%.*}" = "7" ]; then \
-        install-php-extensions amqp \
-        && install-php-extensions $(echo "$PHP_EXTENSIONS" | sed 's/amqp//'); \
+        retry install-php-extensions amqp \
+        && retry install-php-extensions $(echo "$PHP_EXTENSIONS" | sed 's/amqp//'); \
     else \
-        install-php-extensions $PHP_EXTENSIONS; \
+        retry install-php-extensions $PHP_EXTENSIONS; \
     fi \
     && if command -v a2enmod; then a2enmod rewrite; fi
 
diff --git a/Dockerfile.alpine b/Dockerfile.alpine
index 5fa4e50..fec2854 100644
--- a/Dockerfile.alpine
+++ b/Dockerfile.alpine
@@ -9,7 +9,9 @@ RUN chmod +x /usr/local/bin/install-php-extensions
 # PEAR < 1.10.18 can't read pecl.php.net responses anymore.
 RUN pear upgrade --force https://pear.php.net/get/PEAR-1.10.18.tgz
 
-RUN apk add --no-cache \
+# retry: PECL sometimes replies "No releases available" on CI runners.
+RUN retry() { for i in 1 2 3; do "$@" && return; sleep 10; done; return 1; }; \
+    apk add --no-cache \
       coreutils \
       curl \
       git \
@@ -43,7 +45,7 @@ RUN apk add --no-cache \
       5.6.*) PHP_EXTENSIONS="$PHP_EXTENSIONS mcrypt mysql";; \
       7.0.*|7.1.*) PHP_EXTENSIONS="$PHP_EXTENSIONS mcrypt";; \
     esac \
-    && install-php-extensions $PHP_EXTENSIONS \
+    && retry install-php-extensions $PHP_EXTENSIONS \
     && if command -v a2enmod; then a2enmod rewrite; fi
 
 # Install Composer.
diff --git a/compat/Dockerfile.5.6 b/compat/Dockerfile.5.6
index b296db7..6338d40 100644
--- a/compat/Dockerfile.5.6
+++ b/compat/Dockerfile.5.6
@@ -214,7 +214,9 @@ RUN chmod +x /usr/local/bin/install-php-extensions
 # PEAR < 1.10.18 can't read pecl.php.net responses anymore.
 RUN pear upgrade --force https://pear.php.net/get/PEAR-1.10.18.tgz
 
-RUN DEBIAN_FRONTEND=noninteractive apt-get update -q \
+# retry: PECL sometimes replies "No releases available" on CI runners.
+RUN retry() { for i in 1 2 3; do "$@" && return; sleep 10; done; return 1; }; \
+    DEBIAN_FRONTEND=noninteractive apt-get update -q \
     && DEBIAN_FRONTEND=noninteractive apt-get install -qq -y \
       curl \
       git \
@@ -246,7 +248,7 @@ RUN DEBIAN_FRONTEND=noninteractive apt-get update -q \
       xsl \
       zip \
     " \
-    && install-php-extensions $PHP_EXTENSIONS
+    && retry install-php-extensions $PHP_EXTENSIONS
 
 # Install Composer.
 ENV PATH=$PATH:/root/composer/vendor/bin \
diff --git a/compat/Dockerfile.5.6-apache b/compat/Dockerfile.5.6-apache
index 92eff7b..365fb8f 100644
--- a/compat/Dockerfile.5.6-apache
+++ b/compat/Dockerfile.5.6-apache
@@ -278,7 +278,9 @@ RUN chmod +x /usr/local/bin/install-php-extensions
 # PEAR < 1.10.18 can't read pecl.php.net responses anymore.
 RUN pear upgrade --force https://pear.php.net/get/PEAR-1.10.18.tgz
 
-RUN DEBIAN_FRONTEND=noninteractive apt-get update -q \
+# retry: PECL sometimes replies "No releases available" on CI runners.
+RUN retry() { for i in 1 2 3; do "$@" && return; sleep 10; done; return 1; }; \
+    DEBIAN_FRONTEND=noninteractive apt-get update -q \
     && DEBIAN_FRONTEND=noninteractive apt-get install -qq -y \
       curl \
       git \
@@ -310,7 +312,7 @@ RUN DEBIAN_FRONTEND=noninteractive apt-get update -q \
       xsl \
       zip \
     " \
-    && install-php-extensions $PHP_EXTENSIONS \
+    && retry install-php-extensions $PHP_EXTENSIONS \
     && if command -v a2enmod; then a2enmod rewrite; fi
 
 # Install Composer.
diff --git a/compat/Dockerfile.5.6-fpm b/compat/Dockerfile.5.6-fpm
index f6e4c84..dec3b1f 100644
--- a/compat/Dockerfile.5.6-fpm
+++ b/compat/Dockerfile.5.6-fpm
@@ -254,7 +254,9 @@ RUN chmod +x /usr/local/bin/install-php-extensions
 # PEAR < 1.10.18 can't read pecl.php.net responses anymore.
 RUN pear upgrade --force https://pear.php.net/get/PEAR-1.10.18.tgz
 
-RUN DEBIAN_FRONTEND=noninteractive apt-get update -q \
+# retry: PECL sometimes replies "No releases available" on CI runners.
+RUN retry() { for i in 1 2 3; do "$@" && return; sleep 10; done; return 1; }; \
+    DEBIAN_FRONTEND=noninteractive apt-get update -q \
     && DEBIAN_FRONTEND=noninteractive apt-get install -qq -y \
       curl \
       git \
@@ -286,7 +288,7 @@ RUN DEBIAN_FRONTEND=noninteractive apt-get update -q \
       xsl \
       zip \
     " \
-    && install-php-extensions $PHP_EXTENSIONS
+    && retry install-php-extensions $PHP_EXTENSIONS
 
 # Install Composer.
 ENV PATH=$PATH:/root/composer/vendor/bin \
diff --git a/dev/Dockerfile b/dev/Dockerfile
index 9e7190e..63ff3f7 100644
--- a/dev/Dockerfile
+++ b/dev/Dockerfile
@@ -3,4 +3,6 @@ FROM ${BASE_IMAGE}
 LABEL maintainer="dev@chialab.io"
 
 # Install XDebug.
-RUN install-php-extensions xdebug
+# retry: PECL sometimes replies "No releases available" on CI runners.
+RUN retry() { for i in 1 2 3; do "$@" && return; sleep 10; done; return 1; }; \
+    retry install-php-extensions xdebug
diff --git a/otel/Dockerfile b/otel/Dockerfile
index 4ad18fd..7ec51c9 100644
--- a/otel/Dockerfile
+++ b/otel/Dockerfile
@@ -2,8 +2,10 @@ ARG BASE_IMAGE=chialab/php:latest
 FROM ${BASE_IMAGE}
 LABEL maintainer="dev@chialab.io"
 
-RUN if [ "$(echo "$PHP_VERSION" | cut -d. -f1,2)" = "8.0" ]; then \
-        install-php-extensions protobuf opentelemetry-php/ext-opentelemetry@1.1.3; \
+# retry: PECL sometimes replies "No releases available" on CI runners.
+RUN retry() { for i in 1 2 3; do "$@" && return; sleep 10; done; return 1; }; \
+    if [ "$(echo "$PHP_VERSION" | cut -d. -f1,2)" = "8.0" ]; then \
+        retry install-php-extensions protobuf opentelemetry-php/ext-opentelemetry@1.1.3; \
     else \
-        install-php-extensions protobuf opentelemetry-php/ext-opentelemetry@1.3.1; \
+        retry install-php-extensions protobuf opentelemetry-php/ext-opentelemetry@1.3.1; \
     fi
diff --git a/pcov/Dockerfile b/pcov/Dockerfile
index 34c589c..0137510 100644
--- a/pcov/Dockerfile
+++ b/pcov/Dockerfile
@@ -3,4 +3,6 @@ FROM ${BASE_IMAGE}
 LABEL maintainer="dev@chialab.io"
 
 # Install PCOV.
-RUN install-php-extensions pcov
+# retry: PECL sometimes replies "No releases available" on CI runners.
+RUN retry() { for i in 1 2 3; do "$@" && return; sleep 10; done; return 1; }; \
+    retry install-php-extensions pcov
diff --git a/xhprof/Dockerfile b/xhprof/Dockerfile
index 6f6da20..4e54d32 100644
--- a/xhprof/Dockerfile
+++ b/xhprof/Dockerfile
@@ -3,4 +3,6 @@ FROM ${BASE_IMAGE}
 LABEL maintainer="dev@chialab.io"
 
 # Install XHProf.
-RUN install-php-extensions xhprof
+# retry: PECL sometimes replies "No releases available" on CI runners.
+RUN retry() { for i in 1 2 3; do "$@" && return; sleep 10; done; return 1; }; \
+    retry install-php-extensions xhprof