diff --git a/Cargo.lock b/Cargo.lock
index cffea46..331b617 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -112,6 +112,12 @@ version = "3.20.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "5d20789868f4b01b2f2caec9f5c4e0213b41e3e5702a50157d699ae31ced2fcb"
 
+[[package]]
+name = "byteorder"
+version = "1.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1fd0f2584146f6f2ef48085050886acf353beff7305ebd1ae69500e27c67f64b"
+
 [[package]]
 name = "bytes"
 version = "1.11.1"
@@ -220,6 +226,21 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "crc"
+version = "3.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5eb8a2a1cd12ab0d987a5d5e825195d372001a4094a0376319d5a0ad71c1ba0d"
+dependencies = [
+ "crc-catalog",
+]
+
+[[package]]
+name = "crc-catalog"
+version = "2.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "217698eaf96b4a3f0bc4f3662aaa55bdf913cd54d7204591faa790070c6d0853"
+
 [[package]]
 name = "crc32fast"
 version = "1.5.0"
@@ -783,6 +804,7 @@ dependencies = [
  "fs_extra",
  "humantime",
  "lsp-types",
+ "lzma-rs",
  "regex",
  "reqwest",
  "serde",
@@ -811,6 +833,16 @@ dependencies = [
  "serde_repr",
 ]
 
+[[package]]
+name = "lzma-rs"
+version = "0.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "297e814c836ae64db86b36cf2a557ba54368d03f6afcd7d947c266692f71115e"
+dependencies = [
+ "byteorder",
+ "crc",
+]
+
 [[package]]
 name = "memchr"
 version = "2.8.0"
diff --git a/Cargo.toml b/Cargo.toml
index fb1982a..9282c7e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -27,6 +27,7 @@ command-group = "5.0.1"
 flate2 = "1.1.5"
 humantime = "2.3.0"
 lsp-types = "0.97.0"
+lzma-rs = "0.3.0"
 regex = "1.11.1"
 reqwest = { version = "0.12.24", default-features = false, features = ["blocking", "json", "rustls-tls"] }
 serde = { version = "1.0.228", features = ["derive"] }
diff --git a/activate.sh b/activate.sh
index 8e1fe48..bc58a6d 100644
--- a/activate.sh
+++ b/activate.sh
@@ -1,6 +1,25 @@
 # Source this from the repo root to put the tools installed by `make download-dev-env`
-# (go, java, node, dotnet) on PATH: `source activate.sh`
+# (go, java, node, dotnet, zig, ruby) on PATH: `source activate.sh`
 case ":$PATH:" in
     *":$PWD/.env/bin:"*) ;;
     *) export PATH="$PWD/.env/bin:$PATH" ;;
 esac
+
+# ruby-builder's prebuilt ruby needs its lib dir on LD_LIBRARY_PATH (RUNPATH points at the
+# hosted-toolcache path it was built for) and RUBYLIB (default $LOAD_PATH is baked in too).
+if [[ -d "$PWD/.env/ruby/lib" ]]; then
+    export LD_LIBRARY_PATH="$PWD/.env/ruby/lib${LD_LIBRARY_PATH:+:$LD_LIBRARY_PATH}"
+    rubylib_entries=()
+    for dir in "$PWD"/.env/ruby/lib/ruby/*/; do
+        [[ -d "$dir" ]] || continue
+        rubylib_entries+=("${dir%/}")
+        for arch_dir in "$dir"*linux*/; do
+            [[ -d "$arch_dir" ]] && rubylib_entries+=("${arch_dir%/}")
+        done
+    done
+    if (( ${#rubylib_entries[@]} > 0 )); then
+        rubylib_joined=$(IFS=:; echo "${rubylib_entries[*]}")
+        export RUBYLIB="$rubylib_joined${RUBYLIB:+:$RUBYLIB}"
+    fi
+    unset rubylib_entries rubylib_joined dir arch_dir
+fi
diff --git a/data b/data
index 27c97a8..ec28c6b 160000
--- a/data
+++ b/data
@@ -1 +1 @@
-Subproject commit 27c97a864a4de20181f1098438e1582ffb187b9a
+Subproject commit ec28c6bf19fa27df7b4c9451ea299743a98e9bf0
diff --git a/playground/clojure/main.clj b/playground/clojure/main.clj
index e69de29..53f7bef 100644
--- a/playground/clojure/main.clj
+++ b/playground/clojure/main.clj
@@ -0,0 +1,16 @@
+(ns main)
+
+(defrecord OrderItem [name quantity price])
+
+(defrecord Order [customer items])
+
+(defn order-total [order]
+  (reduce + (map (fn [item] (* (:quantity item) (:price item))) (:items order))))
+
+(defn build-sample-order []
+  (->Order "Carol" [(->OrderItem "Mouse" 1 35.0) (->OrderItem "Pad" 1 12.5)]))
+
+(defn format-order [order]
+  (str (:customer order) " has " (count (:items order)) " items worth " (order-total order)))
+
+(println (format-order (build-sample-order)))
diff --git a/playground/luau/main.luau b/playground/luau/main.luau
index e69de29..8bc4308 100644
--- a/playground/luau/main.luau
+++ b/playground/luau/main.luau
@@ -0,0 +1,35 @@
+type OrderItem = {
+    name: string,
+    quantity: number,
+    price: number,
+}
+
+type Order = {
+    customer: string,
+    items: { OrderItem },
+}
+
+local function order_total(order: Order): number
+    local sum = 0
+    for _, item in order.items do
+        sum += item.quantity * item.price
+    end
+    return sum
+end
+
+local function build_sample_order(): Order
+    return {
+        customer = "Carol",
+        items = {
+            { name = "Mouse", quantity = 1, price = 35.0 },
+            { name = "Pad", quantity = 1, price = 12.5 },
+        },
+    }
+end
+
+local function format_order(order: Order): string
+    return string.format("%s has %d items worth %.2f", order.customer, #order.items, order_total(order))
+end
+
+local order = build_sample_order()
+print(format_order(order))
diff --git a/playground/odin/main.odin b/playground/odin/main.odin
index e69de29..a0b6656 100644
--- a/playground/odin/main.odin
+++ b/playground/odin/main.odin
@@ -0,0 +1,42 @@
+package main
+
+import "core:fmt"
+
+OrderItem :: struct {
+	name:     string,
+	quantity: int,
+	price:    f64,
+}
+
+Order :: struct {
+	customer: string,
+	items:    []OrderItem,
+}
+
+order_total :: proc(order: Order) -> f64 {
+	sum := 0.0
+	for item in order.items {
+		sum += f64(item.quantity) * item.price
+	}
+	return sum
+}
+
+build_sample_order :: proc() -> Order {
+	return Order{
+		customer = "Carol",
+		items = []OrderItem{
+			{name = "Mouse", quantity = 1, price = 35.0},
+			{name = "Pad", quantity = 1, price = 12.5},
+		},
+	}
+}
+
+format_order :: proc(order: Order) -> string {
+	total := order_total(order)
+	return fmt.tprintf("%s has %d items worth %.2f", order.customer, len(order.items), total)
+}
+
+main :: proc() {
+	order := build_sample_order()
+	fmt.println(format_order(order))
+}
diff --git a/playground/perl/lib/Order.pm b/playground/perl/lib/Order.pm
new file mode 100644
index 0000000..034c750
--- /dev/null
+++ b/playground/perl/lib/Order.pm
@@ -0,0 +1,18 @@
+package Order;
+
+use strict;
+use warnings;
+
+sub new {
+    my ($class, $customer, $items) = @_;
+    return bless { customer => $customer, items => $items }, $class;
+}
+
+sub total {
+    my ($self) = @_;
+    my $sum = 0;
+    $sum += $_->{quantity} * $_->{price} for @{ $self->{items} };
+    return $sum;
+}
+
+1;
diff --git a/playground/perl/lib/OrderItem.pm b/playground/perl/lib/OrderItem.pm
new file mode 100644
index 0000000..06711ed
--- /dev/null
+++ b/playground/perl/lib/OrderItem.pm
@@ -0,0 +1,11 @@
+package OrderItem;
+
+use strict;
+use warnings;
+
+sub new {
+    my ($class, $name, $quantity, $price) = @_;
+    return bless { name => $name, quantity => $quantity, price => $price }, $class;
+}
+
+1;
diff --git a/playground/perl/lib/Report.pm b/playground/perl/lib/Report.pm
new file mode 100644
index 0000000..2e3c277
--- /dev/null
+++ b/playground/perl/lib/Report.pm
@@ -0,0 +1,18 @@
+package Report;
+
+use strict;
+use warnings;
+use Exporter qw(import);
+
+our @EXPORT_OK = qw(format_order);
+
+sub format_order {
+    my ($order) = @_;
+    my $count = scalar @{ $order->{items} };
+    return sprintf(
+        "%s has %d items worth %.2f",
+        $order->{customer}, $count, $order->total
+    );
+}
+
+1;
diff --git a/playground/perl/main.pl b/playground/perl/main.pl
index e69de29..7319594 100644
--- a/playground/perl/main.pl
+++ b/playground/perl/main.pl
@@ -0,0 +1,17 @@
+use strict;
+use warnings;
+use lib 'lib';
+use Order;
+use OrderItem;
+use Report qw(format_order);
+
+sub build_sample_order {
+    my @items = (
+        OrderItem->new("Mouse", 1, 35.0),
+        OrderItem->new("Pad",   1, 12.5),
+    );
+    return Order->new("Carol", \@items);
+}
+
+my $order = build_sample_order();
+print format_order($order), "\n";
diff --git a/playground/ruby/Gemfile b/playground/ruby/Gemfile
new file mode 100644
index 0000000..99ae841
--- /dev/null
+++ b/playground/ruby/Gemfile
@@ -0,0 +1,3 @@
+source "https://rubygems.org"
+
+ruby ">= 3.0"
diff --git a/playground/ruby/lib/order.rb b/playground/ruby/lib/order.rb
new file mode 100644
index 0000000..b92ceed
--- /dev/null
+++ b/playground/ruby/lib/order.rb
@@ -0,0 +1,36 @@
+class OrderItem
+  attr_reader :name, :quantity, :price
+
+  def initialize(name, quantity, price)
+    @name = name
+    @quantity = quantity
+    @price = price
+  end
+
+  def total
+    quantity * price
+  end
+end
+
+class Order
+  attr_reader :customer, :items
+
+  def initialize(customer, items)
+    @customer = customer
+    @items = items
+  end
+
+  def total
+    items.sum(&:total)
+  end
+end
+
+def build_sample_order
+  Order.new(
+    "Carol",
+    [
+      OrderItem.new("Mouse", 1, 35.0),
+      OrderItem.new("Pad", 1, 12.5)
+    ]
+  )
+end
diff --git a/playground/ruby/lib/report.rb b/playground/ruby/lib/report.rb
new file mode 100644
index 0000000..5972d77
--- /dev/null
+++ b/playground/ruby/lib/report.rb
@@ -0,0 +1,3 @@
+def format_order(order)
+  "#{order.customer} has #{order.items.length} items worth #{format('%.2f', order.total)}"
+end
diff --git a/playground/ruby/main.rb b/playground/ruby/main.rb
index e69de29..d2f714e 100644
--- a/playground/ruby/main.rb
+++ b/playground/ruby/main.rb
@@ -0,0 +1,5 @@
+require_relative "lib/order"
+require_relative "lib/report"
+
+order = build_sample_order
+puts format_order(order)
diff --git a/playground/vim/main.vim b/playground/vim/main.vim
index e69de29..693b9de 100644
--- a/playground/vim/main.vim
+++ b/playground/vim/main.vim
@@ -0,0 +1,14 @@
+function! OrderTotal(quantity, price)
+    return a:quantity * a:price
+endfunction
+
+function! BuildSampleOrder()
+    return "Carol"
+endfunction
+
+function! FormatOrder(customer, quantity, price)
+    let total = OrderTotal(a:quantity, a:price)
+    return a:customer . " has " . a:quantity . " items worth " . total
+endfunction
+
+echo FormatOrder(BuildSampleOrder(), 2, 35.0)
diff --git a/playground/zig/build.zig b/playground/zig/build.zig
new file mode 100644
index 0000000..30ee240
--- /dev/null
+++ b/playground/zig/build.zig
@@ -0,0 +1,16 @@
+const std = @import("std");
+
+pub fn build(b: *std.Build) void {
+    const target = b.standardTargetOptions(.{});
+    const optimize = b.standardOptimizeOption(.{});
+
+    const exe = b.addExecutable(.{
+        .name = "playground",
+        .root_module = b.createModule(.{
+            .root_source_file = b.path("main.zig"),
+            .target = target,
+            .optimize = optimize,
+        }),
+    });
+    b.installArtifact(exe);
+}
diff --git a/playground/zig/main.zig b/playground/zig/main.zig
index e69de29..f3cb6c7 100644
--- a/playground/zig/main.zig
+++ b/playground/zig/main.zig
@@ -0,0 +1,49 @@
+const std = @import("std");
+
+const OrderItem = struct {
+    name: []const u8,
+    quantity: u32,
+    price: f64,
+
+    fn total(self: OrderItem) f64 {
+        return @as(f64, @floatFromInt(self.quantity)) * self.price;
+    }
+};
+
+const Order = struct {
+    customer: []const u8,
+    items: []const OrderItem,
+
+    fn total(self: Order) f64 {
+        var sum: f64 = 0;
+        for (self.items) |item| {
+            sum += item.total();
+        }
+        return sum;
+    }
+};
+
+fn sample_order() Order {
+    return Order{
+        .customer = "Carol",
+        .items = &[_]OrderItem{
+            OrderItem{ .name = "Mouse", .quantity = 1, .price = 35.0 },
+            OrderItem{ .name = "Pad", .quantity = 1, .price = 12.5 },
+        },
+    };
+}
+
+fn format_order(order: Order, buffer: []u8) ![]u8 {
+    return std.fmt.bufPrint(buffer, "{s} has {d} items worth {d:.2}", .{
+        order.customer,
+        order.items.len,
+        order.total(),
+    });
+}
+
+pub fn main() !void {
+    const order = sample_order();
+    var buffer: [128]u8 = undefined;
+    const report = try format_order(order, &buffer);
+    std.debug.print("{s}\n", .{report});
+}
diff --git a/scripts/download_dev_env.sh b/scripts/download_dev_env.sh
index 9cfdb7d..60ab9d6 100755
--- a/scripts/download_dev_env.sh
+++ b/scripts/download_dev_env.sh
@@ -1,12 +1,16 @@
 #!/usr/bin/env bash
 #
-# Downloads the external runtimes needed by the real-server E2E tests (go, java, node, dotnet)
-# into a project-local .env/ directory, so contributors don't need to install them system-wide.
+# Downloads the external runtimes needed by the real-server E2E tests (go, java, node, dotnet,
+# zig, ruby) into a project-local .env/ directory, so contributors don't need to install them
+# system-wide.
 #
 # Default versions mirror .github/workflows/ci.yml / e2e.yml (actions/setup-go,
 # actions/setup-java, actions/setup-node, actions/setup-dotnet). Keep them in sync manually if
 # CI's pins change; override per-tool via GO_VERSION / JAVA_VERSION / NODE_VERSION /
-# DOTNET_CHANNEL.
+# DOTNET_CHANNEL / ZIG_VERSION / RUBY_VERSION.
+#
+# Each runtime's installer lives in scripts/download_dev_env/<name>.inc; add a new one there and
+# source+call it below to add another language.
 #
 # Usage: scripts/download_dev_env.sh
 # Then:  source activate.sh   (from the repo root)
@@ -17,10 +21,13 @@ GO_VERSION="${GO_VERSION:-1.27.1}"
 JAVA_VERSION="${JAVA_VERSION:-21}"
 NODE_VERSION="${NODE_VERSION:-24}"
 DOTNET_CHANNEL="${DOTNET_CHANNEL:-10.0}"
+ZIG_VERSION="${ZIG_VERSION:-0.15.2}"
+RUBY_VERSION="${RUBY_VERSION:-3.3.6}"
 
 repo_root=$(git rev-parse --show-toplevel)
 env_dir="$repo_root/.env"
 bin_dir="$env_dir/bin"
+inc_dir="$repo_root/scripts/download_dev_env"
 
 tmp_dir=$(mktemp -d)
 trap 'rm -rf "$tmp_dir"' EXIT
@@ -63,88 +70,19 @@ link() {
     ln -sf "$target" "$bin_dir/$name"
 }
 
-install_go() {
-    local tool_dir="$env_dir/go"
-    if is_up_to_date "$tool_dir" "$GO_VERSION"; then
-        echo "go $GO_VERSION already installed, skipping"
-        return
-    fi
-    echo "Installing go $GO_VERSION..."
-    local archive="$tmp_dir/go.tar.gz"
-    curl -fsSL -o "$archive" "https://go.dev/dl/go${GO_VERSION}.${os}-${arch/x64/amd64}.tar.gz"
-    rm -rf "$tool_dir"
-    mkdir -p "$tool_dir"
-    tar -xzf "$archive" -C "$tool_dir" --strip-components=1
-    echo "$GO_VERSION" > "$(version_stamp "$tool_dir")"
-    link "$tool_dir/bin/go" go
-    link "$tool_dir/bin/gofmt" gofmt
-}
-
-install_java() {
-    local tool_dir="$env_dir/java"
-    local api_url="https://api.adoptium.net/v3/binary/latest/${JAVA_VERSION}/ga/${os}/${arch}/jdk/hotspot/normal/eclipse"
-    local resolved_version
-    resolved_version=$(curl -fsSIL -o /dev/null -w '%{url_effective}' "$api_url")
-    if is_up_to_date "$tool_dir" "$resolved_version"; then
-        echo "java (Temurin $JAVA_VERSION) already installed, skipping"
-        return
-    fi
-    echo "Installing java (Temurin $JAVA_VERSION)..."
-    local archive="$tmp_dir/java.tar.gz"
-    curl -fsSL -o "$archive" "$api_url"
-    rm -rf "$tool_dir"
-    mkdir -p "$tool_dir"
-    tar -xzf "$archive" -C "$tool_dir" --strip-components=1
-    echo "$resolved_version" > "$(version_stamp "$tool_dir")"
-    link "$tool_dir/bin/java" java
-    link "$tool_dir/bin/javac" javac
-}
-
-install_node() {
-    local tool_dir="$env_dir/node"
-    local index_url="https://nodejs.org/dist/index.json"
-    local resolved_version
-    resolved_version=$(curl -fsSL "$index_url" \
-        | grep -o "\"version\":\"v${NODE_VERSION}\.[0-9]*\.[0-9]*\"" \
-        | head -n1 \
-        | sed -E 's/.*"v([0-9.]+)".*/\1/' || true)
-    if [[ -z "$resolved_version" ]]; then
-        echo "download-dev-env: could not resolve latest node ${NODE_VERSION}.x from $index_url" >&2
-        exit 1
-    fi
-    if is_up_to_date "$tool_dir" "$resolved_version"; then
-        echo "node $resolved_version already installed, skipping"
-        return
-    fi
-    echo "Installing node $resolved_version..."
-    local archive="$tmp_dir/node.tar.xz"
-    curl -fsSL -o "$archive" "https://nodejs.org/dist/v${resolved_version}/node-v${resolved_version}-${os}-${arch}.tar.xz"
-    rm -rf "$tool_dir"
-    mkdir -p "$tool_dir"
-    tar -xJf "$archive" -C "$tool_dir" --strip-components=1
-    echo "$resolved_version" > "$(version_stamp "$tool_dir")"
-    link "$tool_dir/bin/node" node
-    link "$tool_dir/bin/npm" npm
-    link "$tool_dir/bin/npx" npx
-}
-
-install_dotnet() {
-    # dotnet-install.sh is already idempotent: it detects a matching SDK already present in
-    # --install-dir and skips reinstalling it.
-    local tool_dir="$env_dir/dotnet"
-    local install_script="$tmp_dir/dotnet-install.sh"
-    curl -fsSL -o "$install_script" "https://dot.net/v1/dotnet-install.sh"
-    chmod +x "$install_script"
-    echo "Installing dotnet (channel $DOTNET_CHANNEL)..."
-    mkdir -p "$tool_dir"
-    "$install_script" --channel "$DOTNET_CHANNEL" --install-dir "$tool_dir" --no-path
-    link "$tool_dir/dotnet" dotnet
-}
+source "$inc_dir/go.inc"
+source "$inc_dir/java.inc"
+source "$inc_dir/node.inc"
+source "$inc_dir/dotnet.inc"
+source "$inc_dir/zig.inc"
+source "$inc_dir/ruby.inc"
 
 install_go
 install_java
 install_node
 install_dotnet
+install_zig
+install_ruby
 
 echo
 echo "Dev env ready under $env_dir"
diff --git a/scripts/download_dev_env/dotnet.inc b/scripts/download_dev_env/dotnet.inc
new file mode 100644
index 0000000..bec3a83
--- /dev/null
+++ b/scripts/download_dev_env/dotnet.inc
@@ -0,0 +1,12 @@
+install_dotnet() {
+    # dotnet-install.sh is already idempotent: it detects a matching SDK already present in
+    # --install-dir and skips reinstalling it.
+    local tool_dir="$env_dir/dotnet"
+    local install_script="$tmp_dir/dotnet-install.sh"
+    curl -fsSL -o "$install_script" "https://dot.net/v1/dotnet-install.sh"
+    chmod +x "$install_script"
+    echo "Installing dotnet (channel $DOTNET_CHANNEL)..."
+    mkdir -p "$tool_dir"
+    "$install_script" --channel "$DOTNET_CHANNEL" --install-dir "$tool_dir" --no-path
+    link "$tool_dir/dotnet" dotnet
+}
diff --git a/scripts/download_dev_env/go.inc b/scripts/download_dev_env/go.inc
new file mode 100644
index 0000000..384818a
--- /dev/null
+++ b/scripts/download_dev_env/go.inc
@@ -0,0 +1,16 @@
+install_go() {
+    local tool_dir="$env_dir/go"
+    if is_up_to_date "$tool_dir" "$GO_VERSION"; then
+        echo "go $GO_VERSION already installed, skipping"
+        return
+    fi
+    echo "Installing go $GO_VERSION..."
+    local archive="$tmp_dir/go.tar.gz"
+    curl -fsSL -o "$archive" "https://go.dev/dl/go${GO_VERSION}.${os}-${arch/x64/amd64}.tar.gz"
+    rm -rf "$tool_dir"
+    mkdir -p "$tool_dir"
+    tar -xzf "$archive" -C "$tool_dir" --strip-components=1
+    echo "$GO_VERSION" > "$(version_stamp "$tool_dir")"
+    link "$tool_dir/bin/go" go
+    link "$tool_dir/bin/gofmt" gofmt
+}
diff --git a/scripts/download_dev_env/java.inc b/scripts/download_dev_env/java.inc
new file mode 100644
index 0000000..cc57729
--- /dev/null
+++ b/scripts/download_dev_env/java.inc
@@ -0,0 +1,19 @@
+install_java() {
+    local tool_dir="$env_dir/java"
+    local api_url="https://api.adoptium.net/v3/binary/latest/${JAVA_VERSION}/ga/${os}/${arch}/jdk/hotspot/normal/eclipse"
+    local resolved_version
+    resolved_version=$(curl -fsSIL -o /dev/null -w '%{url_effective}' "$api_url")
+    if is_up_to_date "$tool_dir" "$resolved_version"; then
+        echo "java (Temurin $JAVA_VERSION) already installed, skipping"
+        return
+    fi
+    echo "Installing java (Temurin $JAVA_VERSION)..."
+    local archive="$tmp_dir/java.tar.gz"
+    curl -fsSL -o "$archive" "$api_url"
+    rm -rf "$tool_dir"
+    mkdir -p "$tool_dir"
+    tar -xzf "$archive" -C "$tool_dir" --strip-components=1
+    echo "$resolved_version" > "$(version_stamp "$tool_dir")"
+    link "$tool_dir/bin/java" java
+    link "$tool_dir/bin/javac" javac
+}
diff --git a/scripts/download_dev_env/node.inc b/scripts/download_dev_env/node.inc
new file mode 100644
index 0000000..65f7995
--- /dev/null
+++ b/scripts/download_dev_env/node.inc
@@ -0,0 +1,27 @@
+install_node() {
+    local tool_dir="$env_dir/node"
+    local index_url="https://nodejs.org/dist/index.json"
+    local resolved_version
+    resolved_version=$(curl -fsSL "$index_url" \
+        | grep -o "\"version\":\"v${NODE_VERSION}\.[0-9]*\.[0-9]*\"" \
+        | head -n1 \
+        | sed -E 's/.*"v([0-9.]+)".*/\1/' || true)
+    if [[ -z "$resolved_version" ]]; then
+        echo "download-dev-env: could not resolve latest node ${NODE_VERSION}.x from $index_url" >&2
+        exit 1
+    fi
+    if is_up_to_date "$tool_dir" "$resolved_version"; then
+        echo "node $resolved_version already installed, skipping"
+        return
+    fi
+    echo "Installing node $resolved_version..."
+    local archive="$tmp_dir/node.tar.xz"
+    curl -fsSL -o "$archive" "https://nodejs.org/dist/v${resolved_version}/node-v${resolved_version}-${os}-${arch}.tar.xz"
+    rm -rf "$tool_dir"
+    mkdir -p "$tool_dir"
+    tar -xJf "$archive" -C "$tool_dir" --strip-components=1
+    echo "$resolved_version" > "$(version_stamp "$tool_dir")"
+    link "$tool_dir/bin/node" node
+    link "$tool_dir/bin/npm" npm
+    link "$tool_dir/bin/npx" npx
+}
diff --git a/scripts/download_dev_env/ruby.inc b/scripts/download_dev_env/ruby.inc
new file mode 100644
index 0000000..efe077f
--- /dev/null
+++ b/scripts/download_dev_env/ruby.inc
@@ -0,0 +1,28 @@
+install_ruby() {
+    # Prebuilt CRuby from ruby/ruby-builder (same source actions/setup-ruby uses), matched to
+    # this host's Ubuntu release so the dynamically linked build actually runs.
+    local tool_dir="$env_dir/ruby"
+    if is_up_to_date "$tool_dir" "$RUBY_VERSION"; then
+        echo "ruby $RUBY_VERSION already installed, skipping"
+        return
+    fi
+    local ubuntu_codename
+    ubuntu_codename=$(. /etc/os-release && echo "$VERSION_ID")
+    echo "Installing ruby $RUBY_VERSION (ubuntu-${ubuntu_codename})..."
+    local archive="$tmp_dir/ruby.tar.gz"
+    curl -fsSL -o "$archive" "https://github.com/ruby/ruby-builder/releases/download/ruby-${RUBY_VERSION}/ruby-${RUBY_VERSION}-ubuntu-${ubuntu_codename}-x64.tar.gz"
+    rm -rf "$tool_dir"
+    mkdir -p "$tool_dir"
+    tar -xzf "$archive" -C "$tool_dir" --strip-components=1
+    # ruby-builder bakes its hosted-toolcache build path into every bin/ shebang and into the
+    # binary's RUNPATH; rewrite the shebangs to this install's real ruby, and rely on
+    # LD_LIBRARY_PATH (set by the E2E harness / activate.sh) rather than RUNPATH for libruby.
+    for script in "$tool_dir"/bin/*; do
+        [[ -f "$script" ]] || continue
+        sed -i "1s|^#!.*/bin/ruby\$|#!${tool_dir}/bin/ruby|" "$script"
+    done
+    echo "$RUBY_VERSION" > "$(version_stamp "$tool_dir")"
+    link "$tool_dir/bin/ruby" ruby
+    link "$tool_dir/bin/gem" gem
+    link "$tool_dir/bin/bundle" bundle
+}
diff --git a/scripts/download_dev_env/zig.inc b/scripts/download_dev_env/zig.inc
new file mode 100644
index 0000000..4abbb76
--- /dev/null
+++ b/scripts/download_dev_env/zig.inc
@@ -0,0 +1,15 @@
+install_zig() {
+    local tool_dir="$env_dir/zig"
+    if is_up_to_date "$tool_dir" "$ZIG_VERSION"; then
+        echo "zig $ZIG_VERSION already installed, skipping"
+        return
+    fi
+    echo "Installing zig $ZIG_VERSION..."
+    local archive="$tmp_dir/zig.tar.xz"
+    curl -fsSL -o "$archive" "https://ziglang.org/download/${ZIG_VERSION}/zig-x86_64-${os}-${ZIG_VERSION}.tar.xz"
+    rm -rf "$tool_dir"
+    mkdir -p "$tool_dir"
+    tar -xJf "$archive" -C "$tool_dir" --strip-components=1
+    echo "$ZIG_VERSION" > "$(version_stamp "$tool_dir")"
+    link "$tool_dir/zig" zig
+}
diff --git a/src/lsp/client/requests.rs b/src/lsp/client/requests.rs
index 32a2efe..9ad8c3c 100644
--- a/src/lsp/client/requests.rs
+++ b/src/lsp/client/requests.rs
@@ -268,6 +268,8 @@ fn language_id(path: &Path) -> &'static str {
         Some("py") => "python",
         Some("rs") => "rust",
         Some("ts" | "mts" | "cts") => "typescript",
+        Some("vim") => "vim",
+        Some("odin") => "odin",
         _ => "plaintext",
     }
 }
diff --git a/src/mason/install/artifacts.rs b/src/mason/install/artifacts.rs
index b4d18ea..38e940c 100644
--- a/src/mason/install/artifacts.rs
+++ b/src/mason/install/artifacts.rs
@@ -259,6 +259,8 @@ pub(super) fn install_downloaded_artifact(
 
     if relative_name_lower.ends_with(".tar.gz") {
         extract_tar_gz(root, bytes)
+    } else if relative_name_lower.ends_with(".tar.xz") {
+        extract_tar_xz(root, bytes)
     } else if extension.is_some_and(|value| value.eq_ignore_ascii_case("zip")) {
         extract_zip(root, bytes)
     } else if extension.is_some_and(|value| value.eq_ignore_ascii_case("gz")) {
@@ -272,6 +274,55 @@ pub(super) fn install_downloaded_artifact(
 
 fn extract_tar_gz(root: &Path, bytes: &[u8]) -> Result<()> {
     let reader = GzDecoder::new(Cursor::new(bytes));
+    unpack_tar(root, reader)
+}
+
+fn extract_tar_xz(root: &Path, bytes: &[u8]) -> Result<()> {
+    let mut decompressed = BoundedWriter::new(MAX_DECOMPRESSED_BYTES);
+    lzma_rs::xz_decompress(&mut Cursor::new(bytes), &mut decompressed).map_err(
+        format_root_error("failed to decompress downloaded xz archive in", root),
+    )?;
+    unpack_tar(root, Cursor::new(decompressed.into_inner()))
+}
+
+/// A `Write` sink that errors once more than `limit` bytes have been written, guarding xz
+/// decompression (which lzma-rs only exposes as "decompress fully into a sink") against
+/// decompression bombs the way the streaming tar.gz/zip paths already are per-entry.
+struct BoundedWriter {
+    buffer: Vec<u8>,
+    limit: u64,
+}
+
+impl BoundedWriter {
+    fn new(limit: u64) -> Self {
+        Self {
+            buffer: Vec::new(),
+            limit,
+        }
+    }
+
+    fn into_inner(self) -> Vec<u8> {
+        self.buffer
+    }
+}
+
+impl std::io::Write for BoundedWriter {
+    fn write(&mut self, data: &[u8]) -> std::io::Result<usize> {
+        if self.buffer.len() as u64 + data.len() as u64 > self.limit {
+            return Err(std::io::Error::other(
+                "decompressed archive exceeds size limit",
+            ));
+        }
+        self.buffer.extend_from_slice(data);
+        Ok(data.len())
+    }
+
+    fn flush(&mut self) -> std::io::Result<()> {
+        Ok(())
+    }
+}
+
+fn unpack_tar(root: &Path, reader: impl Read) -> Result<()> {
     let mut archive = Archive::new(reader);
     for entry in archive.entries().map_err(format_root_error(
         "failed to open downloaded tar archive in",
diff --git a/tests/e2e/cases/clojure.yaml b/tests/e2e/cases/clojure.yaml
index 8feb7d5..d300922 100644
--- a/tests/e2e/cases/clojure.yaml
+++ b/tests/e2e/cases/clojure.yaml
@@ -1,9 +1,36 @@
 language:
   id: clojure
-  kind: metadata
+  kind: source
   project: playground/clojure
+  query-profile:
+    symbol-query: Order
+    callable-query: build-sample-order
+    format-file: main.clj
+    expected-names:
+      - Order
+      - OrderItem
+      - build-sample-order
+      - format-order
 pairs:
   - language: clojure
     server: clojure_lsp
     smoke:
-      status: capabilities
+      status: queries
+      exceptions:
+        - command: grep
+          outcome: empty-matches
+          reason: clojure-lsp returns no workspace/symbol matches for this fixture
+        - command: callers
+          outcome: empty-matches
+          reason: build-sample-order is only called from top-level code, not from another named function
+        - command: declaration
+          outcome: empty-matches
+          reason: clojure-lsp returns no textDocument/declaration matches for this fixture
+        - command: build-index
+          outcome: failure
+          message: background-work progress
+          reason: clojure-lsp exposes no background-work progress signal
+    lifecycle:
+      status: scenarios
+      direct-run:
+        status: exchange
diff --git a/tests/e2e/cases/luau.yaml b/tests/e2e/cases/luau.yaml
index e3a1321..89592b5 100644
--- a/tests/e2e/cases/luau.yaml
+++ b/tests/e2e/cases/luau.yaml
@@ -1,9 +1,30 @@
 language:
   id: luau
-  kind: metadata
+  kind: source
   project: playground/luau
+  query-profile:
+    symbol-query: Order
+    callable-query: build_sample_order
+    format-file: main.luau
+    expected-names:
+      - Order
+      - OrderItem
+      - build_sample_order
+      - format_order
 pairs:
   - language: luau
     server: luau_lsp
     smoke:
-      status: capabilities
+      status: queries
+      exceptions:
+        - command: callees
+          outcome: empty-matches
+          reason: build_sample_order constructs data directly and has no outgoing call-hierarchy edges
+        - command: build-index
+          outcome: failure
+          message: background-work progress
+          reason: luau-lsp exposes no background-work progress signal
+    lifecycle:
+      status: scenarios
+      direct-run:
+        status: exchange
diff --git a/tests/e2e/cases/odin.yaml b/tests/e2e/cases/odin.yaml
index 6d7d791..75a0653 100644
--- a/tests/e2e/cases/odin.yaml
+++ b/tests/e2e/cases/odin.yaml
@@ -1,9 +1,30 @@
 language:
   id: odin
-  kind: metadata
+  kind: source
   project: playground/odin
+  query-profile:
+    symbol-query: Order
+    callable-query: build_sample_order
+    format-file: main.odin
+    expected-names:
+      - Order
+      - OrderItem
+      - build_sample_order
+      - format_order
 pairs:
   - language: odin
     server: ols
     smoke:
-      status: capabilities
+      status: queries
+      exceptions:
+        - command: grep
+          outcome: empty-matches
+          reason: ols returns no workspace/symbol matches for this fixture
+        - command: build-index
+          outcome: failure
+          message: background-work progress
+          reason: ols exposes no background-work progress signal
+    lifecycle:
+      status: scenarios
+      direct-run:
+        status: exchange
diff --git a/tests/e2e/cases/perl.yaml b/tests/e2e/cases/perl.yaml
index 21015c3..ca67c57 100644
--- a/tests/e2e/cases/perl.yaml
+++ b/tests/e2e/cases/perl.yaml
@@ -1,9 +1,30 @@
 language:
   id: perl
-  kind: metadata
+  kind: source
   project: playground/perl
+  query-profile:
+    symbol-query: Order
+    callable-query: build_sample_order
+    format-file: main.pl
+    expected-names:
+      - Order
+      - OrderItem
+      - build_sample_order
+      - format_order
 pairs:
   - language: perl
     server: perlnavigator
     smoke:
-      status: capabilities
+      status: queries
+      exceptions:
+        - command: definition
+          outcome: empty-matches
+          reason: perlnavigator does not resolve goto-definition for a sub called from the same file it is defined in
+        - command: build-index
+          outcome: failure
+          message: background-work progress
+          reason: perlnavigator exposes no background-work progress signal
+    lifecycle:
+      status: scenarios
+      direct-run:
+        status: exchange
diff --git a/tests/e2e/cases/suite.yaml b/tests/e2e/cases/suite.yaml
index 2b33e3b..8931389 100644
--- a/tests/e2e/cases/suite.yaml
+++ b/tests/e2e/cases/suite.yaml
@@ -986,6 +986,19 @@ servers:
     owner-language: perl
     provisioning:
       status: download
+      host-programs:
+        - name: node
+          resolve:
+            - which
+            - node
+        - name: npm
+          resolve:
+            - which
+            - npm
+        - name: perl
+          resolve:
+            - which
+            - perl
   - id: perlpls
     owner-language: perl
     provisioning:
diff --git a/tests/e2e/cases/zig.yaml b/tests/e2e/cases/zig.yaml
index efb6e48..a9a3ade 100644
--- a/tests/e2e/cases/zig.yaml
+++ b/tests/e2e/cases/zig.yaml
@@ -1,9 +1,27 @@
 language:
   id: zig
-  kind: metadata
+  kind: source
   project: playground/zig
+  query-profile:
+    symbol-query: Order
+    callable-query: sample_order
+    format-file: main.zig
+    expected-names:
+      - Order
+      - OrderItem
+      - sample_order
+      - format_order
 pairs:
   - language: zig
     server: zls
     smoke:
-      status: capabilities
+      status: queries
+      exceptions:
+        - command: build-index
+          outcome: failure
+          message: background-work progress
+          reason: zls exposes no background-work progress signal
+    lifecycle:
+      status: scenarios
+      direct-run:
+        status: exchange
diff --git a/tests/e2e/harness.rs b/tests/e2e/harness.rs
index 9a8edea..b69baf0 100644
--- a/tests/e2e/harness.rs
+++ b/tests/e2e/harness.rs
@@ -42,6 +42,15 @@ pub(crate) struct E2eContext {
     // The staged `dotnet` apphost resolves its runtime via DOTNET_ROOT rather than PATH, so its
     // install root must be threaded through explicitly once `stage_host_program` resolves it.
     dotnet_root: RefCell<Option<PathBuf>>,
+    // Prebuilt ruby-builder binaries carry a hard-coded RUNPATH and default $LOAD_PATH baked in
+    // at build time, which don't match wherever this sandbox happens to stage them;
+    // LD_LIBRARY_PATH/RUBYLIB are the overrides.
+    ruby_env: RefCell<Option<RubyEnv>>,
+}
+
+struct RubyEnv {
+    lib_dir: PathBuf,
+    rubylib: std::ffi::OsString,
 }
 
 pub(crate) struct E2eOutput {
@@ -93,6 +102,7 @@ impl E2eContext {
             build_dir,
             data_dir: PathBuf::from(env!("CARGO_MANIFEST_DIR")).join("data"),
             dotnet_root: RefCell::new(None),
+            ruby_env: RefCell::new(None),
         })
     }
 
@@ -184,6 +194,32 @@ impl E2eContext {
         {
             *self.dotnet_root.borrow_mut() = Some(root.to_path_buf());
         }
+        if name == "ruby"
+            && let Some(root) = resolved.parent().and_then(Path::parent)
+        {
+            let lib_dir = root.join("lib");
+            let stdlib_root = lib_dir.join("ruby");
+            let mut rubylib_entries = Vec::new();
+            if let Ok(versions) = std::fs::read_dir(&stdlib_root) {
+                for version_dir in versions.flatten().map(|entry| entry.path()) {
+                    rubylib_entries.push(version_dir.clone());
+                    if let Ok(archs) = std::fs::read_dir(&version_dir) {
+                        rubylib_entries.extend(archs.flatten().map(|entry| entry.path()).filter(
+                            |path| {
+                                path.file_name()
+                                    .and_then(|name| name.to_str())
+                                    .is_some_and(|name| name.contains("linux"))
+                            },
+                        ));
+                    }
+                }
+            }
+            if lib_dir.is_dir() && !rubylib_entries.is_empty() {
+                let rubylib = std::env::join_paths(&rubylib_entries)
+                    .map_err(|error| format!("failed to build RUBYLIB for staged ruby: {error}"))?;
+                *self.ruby_env.borrow_mut() = Some(RubyEnv { lib_dir, rubylib });
+            }
+        }
 
         self.link_host_program(&resolved, &self.bin_dir.join(name))
             .map_err(|error| {
@@ -272,6 +308,11 @@ impl E2eContext {
         if let Some(root) = self.dotnet_root.borrow().as_deref() {
             command.env("DOTNET_ROOT", root);
         }
+        if let Some(ruby_env) = self.ruby_env.borrow().as_ref() {
+            command
+                .env("LD_LIBRARY_PATH", &ruby_env.lib_dir)
+                .env("RUBYLIB", &ruby_env.rubylib);
+        }
         command
     }