diff --git a/src/user.zig b/src/user.zig
index def7929..692b62a 100644
--- a/src/user.zig
+++ b/src/user.zig
@@ -124,9 +124,8 @@ pub const PackedUser = struct {
     // packTo packs the User record and copies it to the given byte slice. The
     // slice must have at least maxRecordSize() bytes available.
     pub fn packTo(buf1: *[]u8, user: User, shellIndexFn: shellIndexFnType) error{InvalidRecord}!void {
-        std.debug.print("\nbuf1.len: {d}\n", .{buf1.*.len});
         var buf = buf1.*;
-        const bufStart = @ptrToInt(&buf[0]);
+        const bufStart = @ptrToInt(buf.ptr);
 
         const home_len = try downCast(u6, user.home.len - 1);
         const name_len = try downCast(u5, user.name.len - 1);
@@ -150,27 +149,32 @@ pub const PackedUser = struct {
             .gecos_len = gecos_len,
         };
         const innerBytes = mem.asBytes(&inner);
+        buf.len += innerBytes.len +
+            user.home.len +
+            user.gecos.len;
 
-        mem.copy(u8, buf, innerBytes);
+        mem.copy(u8, buf[0..innerBytes.len], innerBytes);
         buf = buf[innerBytes.len..];
-        mem.copy(u8, buf, user.home);
+        mem.copy(u8, buf[0..user.home.len], user.home);
         buf = buf[user.home.len..];
 
         if (!inner.name_is_a_suffix) {
-            mem.copy(u8, buf, user.name);
+            buf.len += user.name.len;
+            mem.copy(u8, buf[0..user.name.len], user.name);
             buf = buf[user.name.len..];
         }
         mem.copy(u8, buf, user.gecos);
         buf = buf[user.gecos.len..];
         if (inner.shell_here) {
-            mem.copy(u8, buf, user.shell);
+            buf.len += user.shell.len;
+            mem.copy(u8, buf[0..user.shell.len], user.shell);
             buf = buf[user.shell.len..];
         }
 
-        _ = bufStart;
-        //const bufLen = @ptrToInt(&buf[0]) - bufStart;
-        //const padding = pad.roundUpPadding(u64, PackedUserAlignmentBits, bufLen);
-        //mem.set(u8, buf[0..padding], 0);
+        const bufLen = @ptrToInt(buf.ptr) - bufStart;
+        const padding = pad.roundUpPadding(u64, PackedUserAlignmentBits, bufLen);
+        buf.len += padding;
+        mem.set(u8, buf[0..padding], 0);
     }
 
     // maxSize is the maximum number of records a PackedUser can take
@@ -358,10 +362,7 @@ test "construct PackedUser section" {
         .shell = "s" ** 64,
     } };
     for (users) |user| {
-        std.debug.print("\nmaxSize: {d}\n", .{PackedUser.maxSize()});
         try buf.ensureUnusedCapacity(PackedUser.maxSize());
-        buf.items[0] = 1;
-        std.debug.print("\nbuf.items.len: {d}\n", .{buf.items.len});
         try PackedUser.packTo(&buf.items, user, testShellIndex);
     }