diff --git a/build.sc b/build.sc
index defb4449d3c..079c07f40c3 100644
--- a/build.sc
+++ b/build.sc
@@ -142,7 +142,7 @@ object Deps {
   val log4j2Core = ivy"org.apache.logging.log4j:log4j-core:2.22.1"
   val osLib = ivy"com.lihaoyi::os-lib:0.9.3"
   val pprint = ivy"com.lihaoyi::pprint:0.8.1"
-  val mainargs = ivy"com.lihaoyi::mainargs:0.5.4"
+  val mainargs = ivy"com.lihaoyi::mainargs:0.6.1"
   val millModuledefsVersion = "0.10.9"
   val millModuledefsString = s"com.lihaoyi::mill-moduledefs:${millModuledefsVersion}"
   val millModuledefs = ivy"${millModuledefsString}"
@@ -1210,7 +1210,6 @@ def launcherScript(
 ) = {
 
   val millMainClass = "mill.main.client.MillClientMain"
-  val millClientMainClass = "mill.main.client.MillClientMain"
 
   Jvm.universalScript(
     shellCommands = {
@@ -1264,15 +1263,20 @@ def launcherScript(
          |    fi
          |    ${java(millMainClass, true)}
          |else
-         |    case "$$1" in
-         |      -i | --interactive | --repl | --no-server | --bsp )
+         |    if [ "$${1%"-i"*}" != "$$1" ] ; then # first arg starts with "-i"
          |        init_mill_jvm_opts
          |        ${java(millMainClass, true)}
-         |        ;;
-         |      *)
-         |        ${java(millClientMainClass, false)}
-         |        ;;
-         |esac
+         |    else
+         |        case "$$1" in
+         |          -i | --interactive | --repl | --no-server | --bsp )
+         |            init_mill_jvm_opts
+         |            ${java(millMainClass, true)}
+         |            ;;
+         |          *)
+         |            ${java(millMainClass, false)}
+         |            ;;
+         |        esac
+         |    fi
          |fi
          |""".stripMargin
     },
@@ -1307,7 +1311,7 @@ def launcherScript(
          |  )
          |  ${java(millMainClass, true)}
          |) else (
-         |  ${java(millClientMainClass, false)}
+         |  ${java(millMainClass, false)}
          |)
          |endlocal
          |""".stripMargin
diff --git a/integration/feature/docannotations/test/src/DocAnnotationsTests.scala b/integration/feature/docannotations/test/src/DocAnnotationsTests.scala
index 855cac4e00a..f86cdb04f2d 100644
--- a/integration/feature/docannotations/test/src/DocAnnotationsTests.scala
+++ b/integration/feature/docannotations/test/src/DocAnnotationsTests.scala
@@ -87,19 +87,20 @@ object DocAnnotationsTests extends IntegrationTestSuite {
       assert(eval("inspect", "core.ivyDepsTree"))
 
       val ivyDepsTree = ujson.read(meta("inspect"))("value").str
+
       assert(
         globMatches(
           """core.ivyDepsTree(JavaModule.scala:...)
             |    Command to print the transitive dependency tree to STDOUT.
             |
-            |    --inverse              Invert the tree representation, so that the root is on the bottom val
-            |                           inverse (will be forced when used with whatDependsOn)
-            |    --whatDependsOn <str>  Possible list of modules (org:artifact) to target in the tree in order to
-            |                           see where a dependency stems from.
-            |    --withCompile          Include the compile-time only dependencies (`compileIvyDeps`, provided
-            |                           scope) into the tree.
-            |    --withRuntime          Include the runtime dependencies (`runIvyDeps`, runtime scope) into the
-            |                           tree.
+            |    --inverse                Invert the tree representation, so that the root is on the bottom val
+            |                             inverse (will be forced when used with whatDependsOn)
+            |    --what-depends-on <str>  Possible list of modules (org:artifact) to target in the tree in order
+            |                             to see where a dependency stems from.
+            |    --with-compile           Include the compile-time only dependencies (`compileIvyDeps`, provided
+            |                             scope) into the tree.
+            |    --with-runtime           Include the runtime dependencies (`runIvyDeps`, runtime scope) into the
+            |                             tree.
             |
             |Inputs:
             |    core.transitiveIvyDeps
@@ -107,6 +108,11 @@ object DocAnnotationsTests extends IntegrationTestSuite {
           ivyDepsTree
         )
       )
+
+      // Make sure both kebab-case and camelCase flags work, even though the
+      // docs from `inspect` only show the kebab-case version
+      assert(eval("core.ivyDepsTree", "--withCompile", "--withRuntime"))
+      assert(eval("core.ivyDepsTree", "--with-compile", "--with-runtime"))
     }
   }
 }
diff --git a/main/client/src/mill/main/client/MillClientMain.java b/main/client/src/mill/main/client/MillClientMain.java
index b82d5d6baed..e6b7d3a3969 100644
--- a/main/client/src/mill/main/client/MillClientMain.java
+++ b/main/client/src/mill/main/client/MillClientMain.java
@@ -61,8 +61,8 @@ public static void main(String[] args) throws Exception {
         if (args.length > 0) {
             String firstArg = args[0];
             runIsolated =
-                Arrays.asList("-i", "--interactive", "--no-server", "--repl", "--bsp", "--help")
-                    .contains(firstArg);
+                Arrays.asList("--interactive", "--no-server", "--repl", "--bsp", "--help")
+                    .contains(firstArg) || firstArg.startsWith("-i");
         }
         if (!runIsolated) {
             // WSL2 has the directory /run/WSL/ and WSL1 not.
diff --git a/main/resolve/src/mill/resolve/Resolve.scala b/main/resolve/src/mill/resolve/Resolve.scala
index 4dbf6eb7336..090c7738d59 100644
--- a/main/resolve/src/mill/resolve/Resolve.scala
+++ b/main/resolve/src/mill/resolve/Resolve.scala
@@ -146,9 +146,10 @@ object Resolve {
       flattenedArgSigsWithDefaults,
       allowPositional = true,
       allowRepeats = false,
-      allowLeftover = ep.argSigs0.exists(_.reader.isLeftover)
+      allowLeftover = ep.argSigs0.exists(_.reader.isLeftover),
+      nameMapper = mainargs.Util.kebabCaseNameMapper
     ).flatMap { (grouped: TokenGrouping[_]) =>
-      val mainData = ep.asInstanceOf[MainData[_, Any]]
+      val mainData = ep.asInstanceOf[MainData[Any, Any]]
       val mainDataWithDefaults = mainData
         .copy(argSigs0 = mainData.argSigs0.map(withNullDefault))
 
@@ -170,7 +171,8 @@ object Resolve {
             docsOnNewLine = false,
             customName = None,
             customDoc = None,
-            sorted = true
+            sorted = true,
+            nameMapper = mainargs.Util.nullNameMapper
           )
         )
     }
diff --git a/mill b/mill
index 0c5078a0f04..f280687f47b 100755
--- a/mill
+++ b/mill
@@ -53,7 +53,9 @@ if [ -z "$MILL_MAIN_CLI" ] ; then
 fi
 
 MILL_FIRST_ARG=""
-if [ "$1" = "--bsp" ] || [ "$1" = "-i" ] || [ "$1" = "--interactive" ] || [ "$1" = "--no-server" ] || [ "$1" = "--repl" ] || [ "$1" = "--help" ] ; then
+
+ # first arg is a long flag for "--interactive" or starts with "-i"
+if [ "$1" = "--bsp" ] || [ "${1%"-i"*}" != "$1" ] || [ "$1" = "--interactive" ] || [ "$1" = "--no-server" ] || [ "$1" = "--repl" ] || [ "$1" = "--help" ] ; then
   # Need to preserve the first position of those listed options
   MILL_FIRST_ARG=$1
   shift
diff --git a/runner/src/mill/runner/MillCliConfig.scala b/runner/src/mill/runner/MillCliConfig.scala
index e40edc72120..7f707ca512c 100644
--- a/runner/src/mill/runner/MillCliConfig.scala
+++ b/runner/src/mill/runner/MillCliConfig.scala
@@ -20,7 +20,6 @@ class MillCliConfig private (
     )
     val repl: Flag,
     @arg(
-      name = "no-server",
       doc = """Run Mill in single-process mode.
                In this mode, no Mill server will be started or used.
                Must be the first argument."""
@@ -37,13 +36,11 @@ class MillCliConfig private (
     )
     val ringBell: Flag,
     @arg(
-      name = "disable-ticker",
       doc =
         """Disable ticker log (e.g. short-lived prints of stages and progress bars)."""
     )
     val disableTicker: Flag,
     @arg(
-      name = "enable-ticker",
       doc =
         """Enable ticker log (e.g. short-lived prints of stages and progress bars)."""
     )
@@ -52,7 +49,6 @@ class MillCliConfig private (
     @arg(name = "debug", short = 'd', doc = "Show debug output on STDOUT")
     val debugLog: Flag,
     @arg(
-      name = "keep-going",
       short = 'k',
       doc = """Continue build, even after build failures."""
     )
@@ -113,7 +109,6 @@ class MillCliConfig private (
     )
     val color: Option[Boolean],
     @arg(
-      name = "disable-callgraph-invalidation",
       doc =
         """Disable the fine-grained callgraph-based target invalidation in response to
            code changes, and instead fall back to the previous coarse-grained implementation
@@ -121,7 +116,6 @@ class MillCliConfig private (
     )
     val disableCallgraphInvalidation: Flag,
     @arg(
-      name = "meta-level",
       doc =
         """Experimental: Select a meta-build level to run the given targets.
            Level 0 is the normal project, level 1 the first meta-build, and so on.