diff --git a/examples/node-pnpm-custom-node-version/package.json b/examples/node-pnpm-custom-node-version/package.json
index 2779b6886..7b836178c 100644
--- a/examples/node-pnpm-custom-node-version/package.json
+++ b/examples/node-pnpm-custom-node-version/package.json
@@ -18,6 +18,6 @@
     "typescript": "^4.2.4"
   },
   "engines": {
-    "node": ">=14.2 <16"
+    "node": ">=16"
   }
 }
diff --git a/examples/node-yarn-custom-node-version/package.json b/examples/node-yarn-custom-node-version/package.json
index df284e73d..0150345a8 100644
--- a/examples/node-yarn-custom-node-version/package.json
+++ b/examples/node-yarn-custom-node-version/package.json
@@ -6,6 +6,6 @@
     "start": "echo Node version: $(node --version) && node index.js"
   },
   "engines": {
-    "node": ">=14.2 <16"
+    "node": "16.x"
   }
 }
diff --git a/examples/zig/.gitignore b/examples/zig/.gitignore
index f3162a29f..7dc0ebe54 100644
--- a/examples/zig/.gitignore
+++ b/examples/zig/.gitignore
@@ -1 +1,13 @@
-zig-*/
\ No newline at end of file
+# Created by https://www.toptal.com/developers/gitignore/api/zig
+# Edit at https://www.toptal.com/developers/gitignore?templates=zig
+
+### zig ###
+# Zig programming language
+
+zig-cache/
+zig-out/
+build/
+build-*/
+docgen_tmp/
+
+# End of https://www.toptal.com/developers/gitignore/api/zig
diff --git a/examples/zig/build.zig b/examples/zig/build.zig
index 5343eae67..93ff5e05c 100644
--- a/examples/zig/build.zig
+++ b/examples/zig/build.zig
@@ -1,34 +1,70 @@
 const std = @import("std");
 
-pub fn build(b: *std.build.Builder) void {
+// Although this function looks imperative, note that its job is to
+// declaratively construct a build graph that will be executed by an external
+// runner.
+pub fn build(b: *std.Build) void {
     // Standard target options allows the person running `zig build` to choose
     // what target to build for. Here we do not override the defaults, which
     // means any target is allowed, and the default is native. Other options
     // for restricting supported target set are available.
     const target = b.standardTargetOptions(.{});
 
-    // Standard release options allow the person running `zig build` to select
-    // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall.
-    const mode = b.standardReleaseOptions();
+    // Standard optimization options allow the person running `zig build` to select
+    // between Debug, ReleaseSafe, ReleaseFast, and ReleaseSmall. Here we do not
+    // set a preferred release mode, allowing the user to decide how to optimize.
+    const optimize = b.standardOptimizeOption(.{});
 
-    const exe = b.addExecutable("zig", "src/main.zig");
-    exe.setTarget(target);
-    exe.setBuildMode(mode);
-    exe.install();
+    const exe = b.addExecutable(.{
+        .name = "zig",
+        // In this case the main source file is merely a path, however, in more
+        // complicated build scripts, this could be a generated file.
+        .root_source_file = .{ .path = "src/main.zig" },
+        .target = target,
+        .optimize = optimize,
+    });
 
-    const run_cmd = exe.run();
+    // This declares intent for the executable to be installed into the
+    // standard location when the user invokes the "install" step (the default
+    // step when running `zig build`).
+    b.installArtifact(exe);
+
+    // This *creates* a Run step in the build graph, to be executed when another
+    // step is evaluated that depends on it. The next line below will establish
+    // such a dependency.
+    const run_cmd = b.addRunArtifact(exe);
+
+    // By making the run step depend on the install step, it will be run from the
+    // installation directory rather than directly from within the cache directory.
+    // This is not necessary, however, if the application depends on other installed
+    // files, this ensures they will be present and in the expected location.
     run_cmd.step.dependOn(b.getInstallStep());
+
+    // This allows the user to pass arguments to the application in the build
+    // command itself, like this: `zig build run -- arg1 arg2 etc`
     if (b.args) |args| {
         run_cmd.addArgs(args);
     }
 
+    // This creates a build step. It will be visible in the `zig build --help` menu,
+    // and can be selected like this: `zig build run`
+    // This will evaluate the `run` step rather than the default, which is "install".
     const run_step = b.step("run", "Run the app");
     run_step.dependOn(&run_cmd.step);
 
-    const exe_tests = b.addTest("src/main.zig");
-    exe_tests.setTarget(target);
-    exe_tests.setBuildMode(mode);
+    // Creates a step for unit testing. This only builds the test executable
+    // but does not run it.
+    const unit_tests = b.addTest(.{
+        .root_source_file = .{ .path = "src/main.zig" },
+        .target = target,
+        .optimize = optimize,
+    });
+
+    const run_unit_tests = b.addRunArtifact(unit_tests);
 
+    // Similar to creating the run step earlier, this exposes a `test` step to
+    // the `zig build --help` menu, providing a way for the user to request
+    // running the unit tests.
     const test_step = b.step("test", "Run unit tests");
-    test_step.dependOn(&exe_tests.step);
+    test_step.dependOn(&run_unit_tests.step);
 }
diff --git a/examples/zig/src/main.zig b/examples/zig/src/main.zig
index 7b990cb96..ae016d7ae 100644
--- a/examples/zig/src/main.zig
+++ b/examples/zig/src/main.zig
@@ -1,10 +1,13 @@
 const std = @import("std");
 
-pub fn main() anyerror!void {
+pub fn main() !void {
     const stdout = std.io.getStdOut().writer();
-    nosuspend stdout.print("Hello from Zig\n", .{}) catch return;
+    try stdout.print("Hello from {s}!\n", .{"Zig"});
 }
 
-test "basic test" {
-    try std.testing.expectEqual(10, 3 + 7);
+test "simple test" {
+    var list = std.ArrayList(i32).init(std.testing.allocator);
+    defer list.deinit(); // try commenting this out and see if zig detects the memory leak!
+    try list.append(42);
+    try std.testing.expectEqual(@as(i32, 42), list.pop());
 }
diff --git a/src/nixpacks/nix/mod.rs b/src/nixpacks/nix/mod.rs
index 376a66629..1cebca81f 100644
--- a/src/nixpacks/nix/mod.rs
+++ b/src/nixpacks/nix/mod.rs
@@ -6,9 +6,9 @@ use crate::nixpacks::plan::phase::{Phase, Phases};
 pub mod pkg;
 
 // This line is automatically updated.
-// Last Modified: 2023-01-02 17:04:24 UTC+0000
-// https://github.com/NixOS/nixpkgs/commit/293a28df6d7ff3dec1e61e37cc4ee6e6c0fb0847
-pub const NIXPKGS_ARCHIVE: &str = "293a28df6d7ff3dec1e61e37cc4ee6e6c0fb0847";
+// Last Modified: 2023-09-17 17:13:39 UTC+0000
+// https://github.com/NixOS/nixpkgs/commit/5148520bfab61f99fd25fb9ff7bfbb50dad3c9db
+pub const NIXPKGS_ARCHIVE: &str = "5148520bfab61f99fd25fb9ff7bfbb50dad3c9db";
 
 // Version of the Nix archive that uses OpenSSL 1.1
 pub const NIXPACKS_ARCHIVE_LEGACY_OPENSSL: &str = "a0b7e70db7a55088d3de0cc370a59f9fbcc906c3";
diff --git a/src/providers/clojure.rs b/src/providers/clojure.rs
index 3a2c2c52b..a107fe746 100644
--- a/src/providers/clojure.rs
+++ b/src/providers/clojure.rs
@@ -47,7 +47,7 @@ impl Provider for ClojureProvider {
         let mut build = Phase::build(Some(format!("{build_cmd}; {move_file_cmd}")));
         build.depends_on_phase("setup");
 
-        let start = StartPhase::new("bash -c \"java $JAVA_OPTS -jar /app/target/*standalone.jar\"");
+        let start = StartPhase::new("JAR_FILE=$(find ./target -name \"*standalone.jar\"); bash -c \"java $JAVA_OPTS -jar $JAR_FILE\"");
 
         let plan = BuildPlan::new(&vec![setup, build], Some(start));
         Ok(Some(plan))
diff --git a/src/providers/zig.rs b/src/providers/zig.rs
index 5b71466ca..8a46e00b2 100644
--- a/src/providers/zig.rs
+++ b/src/providers/zig.rs
@@ -9,44 +9,28 @@ use crate::nixpacks::{
     },
 };
 use anyhow::Result;
-use std::{env::consts::ARCH, ffi::OsStr};
+use std::ffi::OsStr;
 
 pub struct ZigProvider;
 
-//TODO: CHANGE THIS WHEN ZIG IS UPDATED OR EVERYTHING WILL BREAK!
-const GYRO_VERSION: &str = "0.6.0";
-
 impl Provider for ZigProvider {
     fn name(&self) -> &str {
         "zig"
     }
 
     fn detect(&self, app: &App, _env: &Environment) -> Result<bool> {
-        Ok(app.has_match("*.zig") || app.has_match("**/*.zig") || app.has_match("gyro.zzz"))
+        Ok(app.has_match("*.zig") || app.has_match("**/*.zig"))
     }
 
     fn get_build_plan(&self, app: &App, _env: &Environment) -> Result<Option<BuildPlan>> {
-        let mut setup = Phase::setup(Some(vec![Pkg::new("zig")]));
-
-        if app.includes_file("gyro.zzz") {
-            setup.add_nix_pkgs(&[Pkg::new("wget")]);
-        }
+        let setup = Phase::setup(Some(vec![Pkg::new("zig")]));
 
         let mut install = Phase::install(None);
         if app.includes_file(".gitmodules") {
             install.add_cmd("git submodule update --init".to_string());
         }
-        if app.includes_file("gyro.zzz") {
-            let gyro_exe_path = format!("/gyro/gyro-{GYRO_VERSION}-linux-{ARCH}/bin/gyro");
-            install.add_cmd(format!(
-                "mkdir /gyro && (wget -O- {} | tar -C /gyro -xzf -)",
-                ZigProvider::get_gyro_download_url()
-            ));
-            install.add_cmd(format!("chmod +x {gyro_exe_path}"));
-            install.add_cmd(format!("{gyro_exe_path} fetch"));
-        }
 
-        let build = Phase::build(Some("zig build -Drelease-safe=true".to_string()));
+        let build = Phase::build(Some("zig build -Doptimize=ReleaseSafe".to_string()));
 
         let start = StartPhase::new(format!(
             "./zig-out/bin/{}",
@@ -60,16 +44,3 @@ impl Provider for ZigProvider {
         Ok(Some(plan))
     }
 }
-
-impl ZigProvider {
-    pub fn get_gyro_download_url() -> String {
-        let gyro_supported_archs: Vec<&str> = vec!["x86_64", "aarch64", "i386"];
-        if gyro_supported_archs.contains(&ARCH) {
-            format!(
-                "https://github.com/mattnite/gyro/releases/download/{GYRO_VERSION}/gyro-{GYRO_VERSION}-linux-{ARCH}.tar.gz"
-            )
-        } else {
-            panic!("Gyro is not supported on your architecture ({ARCH}).")
-        }
-    }
-}
diff --git a/tests/docker_run_tests.rs b/tests/docker_run_tests.rs
index d276001e2..b3643e93a 100644
--- a/tests/docker_run_tests.rs
+++ b/tests/docker_run_tests.rs
@@ -551,7 +551,7 @@ async fn test_prisma_postgres_npm_v9() {
 async fn test_yarn_custom_version() {
     let name = simple_build("./examples/node-yarn-custom-node-version").await;
     let output = run_image(&name, None).await;
-    assert!(output.contains("Node version: v14"));
+    assert!(output.contains("Node version: v16"));
 }
 
 #[tokio::test]
diff --git a/tests/snapshots/generate_plan_tests__clojure.snap b/tests/snapshots/generate_plan_tests__clojure.snap
index 70e267c02..2b0a48ce9 100644
--- a/tests/snapshots/generate_plan_tests__clojure.snap
+++ b/tests/snapshots/generate_plan_tests__clojure.snap
@@ -30,6 +30,6 @@ expression: plan
     }
   },
   "start": {
-    "cmd": "bash -c \"java $JAVA_OPTS -jar /app/target/*standalone.jar\""
+    "cmd": "JAR_FILE=$(find ./target -name \"*standalone.jar\"); bash -c \"java $JAVA_OPTS -jar $JAR_FILE\""
   }
 }
diff --git a/tests/snapshots/generate_plan_tests__clojure_jdk11.snap b/tests/snapshots/generate_plan_tests__clojure_jdk11.snap
index de854bb64..6e0cb3356 100644
--- a/tests/snapshots/generate_plan_tests__clojure_jdk11.snap
+++ b/tests/snapshots/generate_plan_tests__clojure_jdk11.snap
@@ -30,6 +30,6 @@ expression: plan
     }
   },
   "start": {
-    "cmd": "bash -c \"java $JAVA_OPTS -jar /app/target/*standalone.jar\""
+    "cmd": "JAR_FILE=$(find ./target -name \"*standalone.jar\"); bash -c \"java $JAVA_OPTS -jar $JAR_FILE\""
   }
 }
diff --git a/tests/snapshots/generate_plan_tests__clojure_jdk_latest.snap b/tests/snapshots/generate_plan_tests__clojure_jdk_latest.snap
index 3106e97bf..fb066b256 100644
--- a/tests/snapshots/generate_plan_tests__clojure_jdk_latest.snap
+++ b/tests/snapshots/generate_plan_tests__clojure_jdk_latest.snap
@@ -30,6 +30,6 @@ expression: plan
     }
   },
   "start": {
-    "cmd": "bash -c \"java $JAVA_OPTS -jar /app/target/*standalone.jar\""
+    "cmd": "JAR_FILE=$(find ./target -name \"*standalone.jar\"); bash -c \"java $JAVA_OPTS -jar $JAR_FILE\""
   }
 }
diff --git a/tests/snapshots/generate_plan_tests__clojure_ring_app.snap b/tests/snapshots/generate_plan_tests__clojure_ring_app.snap
index 801bc5316..327154681 100644
--- a/tests/snapshots/generate_plan_tests__clojure_ring_app.snap
+++ b/tests/snapshots/generate_plan_tests__clojure_ring_app.snap
@@ -30,6 +30,6 @@ expression: plan
     }
   },
   "start": {
-    "cmd": "bash -c \"java $JAVA_OPTS -jar /app/target/*standalone.jar\""
+    "cmd": "JAR_FILE=$(find ./target -name \"*standalone.jar\"); bash -c \"java $JAVA_OPTS -jar $JAR_FILE\""
   }
 }
diff --git a/tests/snapshots/generate_plan_tests__clojure_tools_build.snap b/tests/snapshots/generate_plan_tests__clojure_tools_build.snap
index 141dc98a8..d92b81d03 100644
--- a/tests/snapshots/generate_plan_tests__clojure_tools_build.snap
+++ b/tests/snapshots/generate_plan_tests__clojure_tools_build.snap
@@ -30,6 +30,6 @@ expression: plan
     }
   },
   "start": {
-    "cmd": "bash -c \"java $JAVA_OPTS -jar /app/target/*standalone.jar\""
+    "cmd": "JAR_FILE=$(find ./target -name \"*standalone.jar\"); bash -c \"java $JAVA_OPTS -jar $JAR_FILE\""
   }
 }
diff --git a/tests/snapshots/generate_plan_tests__node_pnpm_custom_node_version.snap b/tests/snapshots/generate_plan_tests__node_pnpm_custom_node_version.snap
index db9041192..022137f04 100644
--- a/tests/snapshots/generate_plan_tests__node_pnpm_custom_node_version.snap
+++ b/tests/snapshots/generate_plan_tests__node_pnpm_custom_node_version.snap
@@ -42,7 +42,7 @@ expression: plan
     "setup": {
       "name": "setup",
       "nixPkgs": [
-        "nodejs-14_x",
+        "nodejs-18_x",
         "pnpm-6_x"
       ],
       "nixOverlays": [
diff --git a/tests/snapshots/generate_plan_tests__node_yarn_custom_node_version.snap b/tests/snapshots/generate_plan_tests__node_yarn_custom_node_version.snap
index a9a6dbb6b..b9a115ee1 100644
--- a/tests/snapshots/generate_plan_tests__node_yarn_custom_node_version.snap
+++ b/tests/snapshots/generate_plan_tests__node_yarn_custom_node_version.snap
@@ -39,7 +39,7 @@ expression: plan
     "setup": {
       "name": "setup",
       "nixPkgs": [
-        "nodejs-14_x",
+        "nodejs-16_x",
         "yarn-1_x"
       ],
       "nixOverlays": [
diff --git a/tests/snapshots/generate_plan_tests__zig.snap b/tests/snapshots/generate_plan_tests__zig.snap
index a78911d44..cb26b5b86 100644
--- a/tests/snapshots/generate_plan_tests__zig.snap
+++ b/tests/snapshots/generate_plan_tests__zig.snap
@@ -15,7 +15,7 @@ expression: plan
         "install"
       ],
       "cmds": [
-        "zig build -Drelease-safe=true"
+        "zig build -Doptimize=ReleaseSafe"
       ]
     },
     "install": {