Fix

fmp-alpine/Dockerfile

@@ -35,7 +35,8 @@ RUN apk add --no-cache --virtual .build-deps \
     libjpeg-turbo-dev \
     libpng-dev \
     icu-dev \
-    libxml2-dev
+    libxml2-dev \
+    linux-headers
 
 RUN docker-php-ext-configure gd \
         --with-freetype \
@@ -47,11 +48,11 @@ RUN docker-php-ext-configure gd \
         zip \
         bcmath \
         soap \
-        sockets \
-        pcntl \
         gd \
         intl \
-        opcache
+        opcache \
+        sockets \
+        pcntl
 
 RUN pecl install imagick \
  && docker-php-ext-enable imagick