diff --git a/build.zig b/build.zig
index dcc25aa..57f12ee 100644
--- a/build.zig
+++ b/build.zig
@@ -1,5 +1,4 @@
 const std = @import("std");
-const builtin = @import("builtin");
 
 // Although this function looks imperative, note that its job is to
 // declaratively construct a build graph that will be executed by an external
diff --git a/src/lambda.zig b/src/lambda.zig
index 8fdf1d7..0d5e571 100644
--- a/src/lambda.zig
+++ b/src/lambda.zig
@@ -1,5 +1,4 @@
 const std = @import("std");
-const builtin = @import("builtin");
 
 pub const HandlerFn = *const fn (std.mem.Allocator, []const u8) anyerror![]const u8;
 
@@ -64,11 +63,11 @@ pub fn run(allocator: ?std.mem.Allocator, event_handler: HandlerFn) !void { // T
         const event = ev.?;
         defer ev.?.deinit();
         const event_response = event_handler(req_allocator, event.event_data) catch |err| {
-            event.reportError(@errorReturnTrace(), err, lambda_runtime_uri) catch unreachable;
+            event.reportError(@errorReturnTrace(), err, lambda_runtime_uri) catch @panic("Error reporting error");
             continue;
         };
         event.postResponse(lambda_runtime_uri, event_response) catch |err| {
-            event.reportError(@errorReturnTrace(), err, lambda_runtime_uri) catch unreachable;
+            event.reportError(@errorReturnTrace(), err, lambda_runtime_uri) catch @panic("Error reporting error");
             continue;
         };
     }
diff --git a/tools/build/src/deploy.zig b/tools/build/src/deploy.zig
index 86f17a4..b8f3ad0 100644
--- a/tools/build/src/deploy.zig
+++ b/tools/build/src/deploy.zig
@@ -148,6 +148,7 @@ fn loadEnvFile(
     defer file.close();
 
     // Read entire file (env files are typically small)
+    // SAFETY: set on read
     var read_buffer: [4096]u8 = undefined;
     var file_reader = file.reader(&read_buffer);
     const content = file_reader.interface.allocRemaining(allocator, std.Io.Limit.limited(64 * 1024)) catch |err| {
@@ -244,6 +245,7 @@ fn deployFunction(deploy_opts: DeployOptions, options: RunOptions) !void {
     // Read the zip file and encode as base64
     const zip_file = try std.fs.cwd().openFile(deploy_opts.zip_file, .{});
     defer zip_file.close();
+    // SAFETY: set on read
     var read_buffer: [4096]u8 = undefined;
     var file_reader = zip_file.reader(&read_buffer);
     const zip_data = try file_reader.interface.allocRemaining(options.allocator, std.Io.Limit.limited(50 * 1024 * 1024));
@@ -278,7 +280,9 @@ fn deployFunction(deploy_opts: DeployOptions, options: RunOptions) !void {
     std.log.info("Attempting to create function: {s}", .{deploy_opts.function_name});
 
     var create_diagnostics = aws.Diagnostics{
+        // SAFETY: set by sdk on error
         .response_status = undefined,
+        // SAFETY: set by sdk on error
         .response_body = undefined,
         .allocator = options.allocator,
     };
@@ -464,6 +468,7 @@ fn addPermission(
     const services = aws.Services(.{.lambda}){};
 
     // Generate statement ID from principal: "alexa-appkit.amazon.com" -> "allow-alexa-appkit-amazon-com"
+    // SAFETY: set on write
     var statement_id_buf: [128]u8 = undefined;
     var statement_id_len: usize = 0;
 
@@ -484,7 +489,9 @@ fn addPermission(
     std.log.info("Adding invoke permission for principal: {s}", .{principal});
 
     var diagnostics = aws.Diagnostics{
+        // SAFETY: set by sdk on error
         .response_status = undefined,
+        // SAFETY: set by sdk on error
         .response_body = undefined,
         .allocator = options.allocator,
     };
@@ -542,6 +549,7 @@ fn writeDeployOutput(
     const file = try std.fs.cwd().createFile(output_path, .{});
     defer file.close();
 
+    // SAFETY: set on write
     var write_buffer: [4096]u8 = undefined;
     var buffered = file.writer(&write_buffer);
     const writer = &buffered.interface;
diff --git a/tools/build/src/iam.zig b/tools/build/src/iam.zig
index 8fa5848..0184a57 100644
--- a/tools/build/src/iam.zig
+++ b/tools/build/src/iam.zig
@@ -61,7 +61,9 @@ pub fn getOrCreateRole(role_name: []const u8, options: RunOptions) ![]const u8 {
     const services = aws.Services(.{.iam}){};
 
     var diagnostics = aws.Diagnostics{
+        // SAFETY: set by sdk on error
         .response_status = undefined,
+        // SAFETY: set by sdk on error
         .response_body = undefined,
         .allocator = options.allocator,
     };
diff --git a/tools/build/src/main.zig b/tools/build/src/main.zig
index f15cdde..9e04c3e 100644
--- a/tools/build/src/main.zig
+++ b/tools/build/src/main.zig
@@ -38,7 +38,7 @@ pub fn main() !u8 {
 
     run(allocator, &stdout_writer.interface, &stderr_writer.interface) catch |err| {
         stderr_writer.interface.print("Error: {}\n", .{err}) catch {};
-        stderr_writer.interface.flush() catch {};
+        try stderr_writer.interface.flush();
         return 1;
     };
     try stderr_writer.interface.flush();