bryan-minimal · Nov 3, 2026 · Oct 16, 2026 · Oct 16, 2026 · Oct 25, 2026 · Nov 2, 2026
@@ -0,0 +1,96 @@
+let { stack, .. } = import "minimal.ncl" in
+# The Java development loadout: one session with everything to write, build,
+# navigate and debug a JVM project, whichever build tool it uses —
+#
+#   javac Hello.java && java Hello      # compile + run (jdk)
+#   jshell                              # REPL (jdk)
+#   mvn -q package                      # Maven projects
+#   gradle build                        # Gradle projects (Groovy or Kotlin DSL)
+#   jdtls                               # LSP for editors / agents (stdio)
+#   jdb -attach 5005                    # debug; jcmd / jfr profile (jdk)
+#   asprof -d 30 -f out.html <pid>      # flamegraph (async-profiler)
+#   google-java-format -i Foo.java      # format; checkstyle / pmd / spotbugs lint
+#   jbang Script.java                   # single-file scripts with //DEPS
+#
+# It is the union of the `maven` and `gradle` stacks' setup plus the language
+# server, pinned to Java 25 (`jdk-25`, the current LTS) like the `maven` and
+# `gradle` stacks, so a project's Java doesn't move when the `jdk` meta rolls
+# to the next LTS; use `jdk-21` / `jdk-27` in the project for another line. The JDK itself is most of the
+# toolbox: javac, jshell, jdb, jcmd, jfr, jdeps, jlink, jpackage, javadoc,
+# javap all ship in it, and jdk-25 links every one into /usr/bin. The tools
+# below the JDK (formatter, linters, profiler, mvnd, kotlinc, jbang) all
+# depend on the `jdk` meta, which is jdk-25 today, so the closure holds one
+# JDK.
+#
+# Opt-in (no `matches_project_if_any`), like `aeneas` and `reveng`: a pom.xml
+# or build.gradle already selects the plain `maven` / `gradle` build stack,
+# and this one must not compete with them. You ask for it explicitly.
+stack {
+  name = "java",
+
+  build_packages = [
+    # Shared base, as in the `maven` / `gradle` stacks. curl because build
+    # tools and wrapper scripts reach for it.
+    "base",
+    "curl",
+
+    # THE ANCHOR: the current LTS JDK (compiler, runtime, jshell, jdb, jfr,
+    # jcmd, jlink, ...). Ships no `JAVA_HOME` of its own — see below.
+    "jdk-25",
+
+    # Both mainstream build tools. Each also works as a launcher for the
+    # project's own plugins (Error Prone, SpotBugs, Spotless, OpenRewrite,
+    # JaCoCo...), which are build-classpath dependencies resolved from Maven
+    # Central rather than packages.
+    "maven",
+    "gradle",
+
+    # Eclipse JDT Language Server: completion, diagnostics, refactoring,
+    # organize-imports and Eclipse-profile formatting over LSP. Its wrapper
+    # already redirects -data / -configuration to a writable cache dir.
+    "jdtls",
+
+    # Everyday tools around the build, each a package on main:
+    "google-java-format", # formatter
+    "checkstyle", # style linter
+    "pmd", # static analysis + CPD
+    "spotbugs", # bytecode bug finder
+    "async-profiler", # CPU/alloc/lock profiler (asprof, jfrconv)
+    "mvnd", # Maven daemon
+    "kotlin", # kotlinc, for Gradle Kotlin DSL / mixed projects
+    "jbang", # run .java scripts with //DEPS
+  ],
+
+  runtime_packages = ["jdk-25"],
+
+  build_env_vars = {
+    # Gradle's and Maven's launchers both want JAVA_HOME and the jdk package
+    # does not set it. Same value the `maven`, `gradle` and `reveng` stacks use.
+    JAVA_HOME = "/usr/lib/jvm",
+
+    # Keep the Maven local repository on the state disk so dependencies
+    # survive between builds (same as the `maven` stack). Gradle needs no
+    # equivalent: the gradle package's env_state_wiring already points
+    # GRADLE_USER_HOME at a state dir.
+    MAVEN_OPTS = "-Dmaven.repo.local=/state/m2/repository",
+  },
+
+  # A dev bench has no single canonical build command (Maven or Gradle?), so
+  # exercise every anchor instead: a session that cannot compile, cannot run
+  # either build tool, cannot start the language server, or has lost the
+  # debugger fails AT START rather than an hour in. jdb is on PATH: jdk-25
+  # links every usr/lib/jvm/bin/* into /usr/bin.
+  build_cmd = "java -version && javac -version && mvn -v && gradle --version && jdtls --help > /dev/null && jdb -version",
+}
+#
+# BUILD PLUGINS, NOT PACKAGES — they ride the project's own pom/build.gradle
+# and resolve from Maven Central, so a package would be dead weight:
+#   Error Prone, Lombok (an annotation processor — a dependency, not a tool),
+#   Spotless, JaCoCo, the OpenRewrite Maven/Gradle plugins.
+#
+# DELIBERATELY ABSENT:
+#   the `mod` OpenRewrite CLI   Moderne's proprietary distribution; and some
+#                               recipe modules moved to a source-available
+#                               (non-OSI) licence. Use the build plugins.
+#   ./mvnw, ./gradlew           wrappers DOWNLOAD a distribution at run time;
+#                               the packaged mvn / gradle are the hermetic path.