diff --git a/lib/docs/wasm/Walk.zig b/lib/docs/wasm/Walk.zig
index 65288b88787750378e1b7a3440a0a2d23b6877d7..688fcbd00af2d7a718750d17fc6174068d400c5e 100644
--- a/lib/docs/wasm/Walk.zig
+++ b/lib/docs/wasm/Walk.zig
@@ -440,7 +440,7 @@ fn parse(file_name: []const u8, source: []u8) Oom!Ast {
             const err_loc = std.zig.findLineColumn(ast.source, err_offset);
             rendered_err.clearRetainingCapacity();
             try ast.renderError(err, rendered_err.writer(gpa));
-            log.err("{s}:{}:{}: {s}", .{ file_name, err_loc.line + 1, err_loc.column + 1, rendered_err.items });
+            log.err("{s}:{d}:{d}: {s}", .{ file_name, err_loc.line + 1, err_loc.column + 1, rendered_err.items });
         }
         return Ast.parse(gpa, "", .zig);
     }
diff --git a/lib/docs/wasm/main.zig b/lib/docs/wasm/main.zig
index d886f8037ca2b23f432828dad7090794df221f4b..7e9ffa5e4c842fa91a54e9c43bfee51aa12e060c 100644
--- a/lib/docs/wasm/main.zig
+++ b/lib/docs/wasm/main.zig
@@ -717,9 +717,9 @@ fn render_docs(
                             try writer.writeAll("<a href=\"#");
                             _ = missing_feature_url_escape;
                             try writer.writeAll(g.link_buffer.items);
-                            try writer.print("\">{}</a>", .{markdown.fmtHtml(content)});
+                            try writer.print("\">{f}</a>", .{markdown.fmtHtml(content)});
                         } else {
-                            try writer.print("{}", .{markdown.fmtHtml(content)});
+                            try writer.print("{f}", .{markdown.fmtHtml(content)});
                         }
 
                         try writer.writeAll("</code>");
diff --git a/lib/docs/wasm/markdown/renderer.zig b/lib/docs/wasm/markdown/renderer.zig
index b01bab7863f33cf35a0abdbd724eee1518dfe24f..cba857d20461c8887dc65957cf2c7b7d6e07ba27 100644
--- a/lib/docs/wasm/markdown/renderer.zig
+++ b/lib/docs/wasm/markdown/renderer.zig
@@ -42,7 +42,7 @@ pub fn Renderer(comptime Writer: type, comptime Context: type) type {
                         if (start == 1) {
                             try writer.writeAll("<ol>\n");
                         } else {
-                            try writer.print("<ol start=\"{}\">\n", .{start});
+                            try writer.print("<ol start=\"{d}\">\n", .{start});
                         }
                     } else {
                         try writer.writeAll("<ul>\n");
@@ -106,15 +106,15 @@ pub fn Renderer(comptime Writer: type, comptime Context: type) type {
                     }
                 },
                 .heading => {
-                    try writer.print("<h{}>", .{data.heading.level});
+                    try writer.print("<h{d}>", .{data.heading.level});
                     for (doc.extraChildren(data.heading.children)) |child| {
                         try r.renderFn(r, doc, child, writer);
                     }
-                    try writer.print("</h{}>\n", .{data.heading.level});
+                    try writer.print("</h{d}>\n", .{data.heading.level});
                 },
                 .code_block => {
                     const content = doc.string(data.code_block.content);
-                    try writer.print("<pre><code>{}</code></pre>\n", .{fmtHtml(content)});
+                    try writer.print("<pre><code>{f}</code></pre>\n", .{fmtHtml(content)});
                 },
                 .blockquote => {
                     try writer.writeAll("<blockquote>\n");
@@ -135,7 +135,7 @@ pub fn Renderer(comptime Writer: type, comptime Context: type) type {
                 },
                 .link => {
                     const target = doc.string(data.link.target);
-                    try writer.print("<a href=\"{}\">", .{fmtHtml(target)});
+                    try writer.print("<a href=\"{f}\">", .{fmtHtml(target)});
                     for (doc.extraChildren(data.link.children)) |child| {
                         try r.renderFn(r, doc, child, writer);
                     }
@@ -143,11 +143,11 @@ pub fn Renderer(comptime Writer: type, comptime Context: type) type {
                 },
                 .autolink => {
                     const target = doc.string(data.text.content);
-                    try writer.print("<a href=\"{0}\">{0}</a>", .{fmtHtml(target)});
+                    try writer.print("<a href=\"{0f}\">{0f}</a>", .{fmtHtml(target)});
                 },
                 .image => {
                     const target = doc.string(data.link.target);
-                    try writer.print("<img src=\"{}\" alt=\"", .{fmtHtml(target)});
+                    try writer.print("<img src=\"{f}\" alt=\"", .{fmtHtml(target)});
                     for (doc.extraChildren(data.link.children)) |child| {
                         try renderInlineNodeText(doc, child, writer);
                     }
@@ -169,11 +169,11 @@ pub fn Renderer(comptime Writer: type, comptime Context: type) type {
                 },
                 .code_span => {
                     const content = doc.string(data.text.content);
-                    try writer.print("<code>{}</code>", .{fmtHtml(content)});
+                    try writer.print("<code>{f}</code>", .{fmtHtml(content)});
                 },
                 .text => {
                     const content = doc.string(data.text.content);
-                    try writer.print("{}", .{fmtHtml(content)});
+                    try writer.print("{f}", .{fmtHtml(content)});
                 },
                 .line_break => {
                     try writer.writeAll("<br />\n");
@@ -222,7 +222,7 @@ pub fn renderInlineNodeText(
         },
         .autolink, .code_span, .text => {
             const content = doc.string(data.text.content);
-            try writer.print("{}", .{fmtHtml(content)});
+            try writer.print("{f}", .{fmtHtml(content)});
         },
         .line_break => {
             try writer.writeAll("\n");
diff --git a/tools/docgen.zig b/tools/docgen.zig
index f270b6b3b0d7fce7c8ddfff4751a8889c3bbf734..3f48ba39a80f686b87a5081380b0bb8aa184aca5 100644
--- a/tools/docgen.zig
+++ b/tools/docgen.zig
@@ -75,9 +75,9 @@ pub fn main() !void {
     var code_dir = try fs.cwd().openDir(code_dir_path, .{});
     defer code_dir.close();
 
-    const input_file_bytes = try in_file.reader().readAllAlloc(arena, max_doc_file_size);
+    const input_file_bytes = try in_file.deprecatedReader().readAllAlloc(arena, max_doc_file_size);
 
-    var buffered_writer = io.bufferedWriter(out_file.writer());
+    var buffered_writer = io.bufferedWriter(out_file.deprecatedWriter());
 
     var tokenizer = Tokenizer.init(input_path, input_file_bytes);
     var toc = try genToc(arena, &tokenizer);
@@ -425,7 +425,7 @@ fn genToc(allocator: Allocator, tokenizer: *Tokenizer) !Toc {
                         try toc.writeByte('\n');
                         try toc.writeByteNTimes(' ', header_stack_size * 4);
                         if (last_columns) |n| {
-                            try toc.print("<ul style=\"columns: {}\">\n", .{n});
+                            try toc.print("<ul style=\"columns: {d}\">\n", .{n});
                         } else {
                             try toc.writeAll("<ul>\n");
                         }
diff --git a/tools/doctest.zig b/tools/doctest.zig
index 4c34ab00e0bda44130f3930831b96170812c480e..8f9d1fe8cf13a503472bbd835d80ea91462174c8 100644
--- a/tools/doctest.zig
+++ b/tools/doctest.zig
@@ -85,7 +85,7 @@ pub fn main() !void {
     var out_file = try fs.cwd().createFile(output_path, .{});
     defer out_file.close();
 
-    var bw = std.io.bufferedWriter(out_file.writer());
+    var bw = std.io.bufferedWriter(out_file.deprecatedWriter());
     const out = bw.writer();
 
     try printSourceBlock(arena, out, source, fs.path.basename(input_path));