Build CI without opam

.travis-ci.sh

@@ -0,0 +1,31 @@
+#!/bin/bash -xue
+
+PATH=~/ocaml/bin:$PATH; export PATH
+
+TARGET="$1"; shift
+
+case "$TARGET" in
+  prepare)
+    if [ ! -e ~/ocaml/cached-version -o "$(cat ~/ocaml/cached-version)" != "$OCAML_VERSION.$OCAML_RELEASE" ] ; then
+      rm -rf ~/ocaml
+      mkdir -p ~/ocaml/src
+      cd ~/ocaml/src
+      wget http://caml.inria.fr/pub/distrib/ocaml-$OCAML_VERSION/ocaml-$OCAML_VERSION.$OCAML_RELEASE.tar.gz
+      tar -xzf ocaml-$OCAML_VERSION.$OCAML_RELEASE.tar.gz
+      cd ocaml-$OCAML_VERSION.$OCAML_RELEASE
+      ./configure -prefix ~/ocaml
+      make world.opt
+      make install
+      cd ..
+      rm -rf src
+      echo "$OCAML_VERSION.$OCAML_RELEASE" > ~/ocaml/cached-version
+    fi
+  ;;
+  build)
+    ocaml bootstrap.ml
+    ./boot.exe --subst
+    ./boot.exe --dev
+  ;;
+  *)
+    echo "bad command $TARGET">&2; exit 1
+esac

.travis.yml

@@ -1,14 +1,20 @@
 language: c
-sudo: required
-install: wget https://raw.githubusercontent.com/ocaml/ocaml-ci-scripts/master/.travis-opam.sh
-script: bash -ex .travis-opam.sh
+sudo: false
+
+cache:
+  directories:
+  - $HOME/ocaml
+
+install: bash -ex .travis-ci.sh prepare
+script: bash -ex .travis-ci.sh build
 env:
   global:
   - PACKAGE=jbuilder
   matrix:
-  - OCAML_VERSION=4.02
-  - OCAML_VERSION=4.03
-  - OCAML_VERSION=4.04
+  - OCAML_VERSION=4.02 OCAML_RELEASE=3
+  - OCAML_VERSION=4.03 OCAML_RELEASE=0
+  - OCAML_VERSION=4.04 OCAML_RELEASE=2
+  - OCAML_VERSION=4.05 OCAML_RELEASE=0+rc1
 os:
   - linux
   - osx