diff --git a/zig/src/http/handler.zig b/zig/src/http/handler.zig
index 415b5c5..889bfed 100644
--- a/zig/src/http/handler.zig
+++ b/zig/src/http/handler.zig
@@ -4,6 +4,9 @@ const Cache = @import("../cache/cache.zig").Cache;
 const WeatherProvider = @import("../weather/provider.zig").WeatherProvider;
 const ansi = @import("../render/ansi.zig");
 const line = @import("../render/line.zig");
+const json = @import("../render/json.zig");
+const v2 = @import("../render/v2.zig");
+const custom = @import("../render/custom.zig");
 const help = @import("help.zig");
 
 pub const HandleWeatherOptions = struct {
@@ -77,15 +80,26 @@ fn handleWeatherInternal(
 
     const query = try req.query();
     const format = query.get("format");
-    const output = if (format) |fmt|
-        try line.render(allocator, weather, fmt)
-    else
-        try ansi.render(allocator, weather, .{});
+
+    const output = if (format) |fmt| blk: {
+        if (std.mem.eql(u8, fmt, "j1")) {
+            res.content_type = .JSON;
+            break :blk try json.render(allocator, weather);
+        } else if (std.mem.eql(u8, fmt, "v2")) {
+            break :blk try v2.render(allocator, weather);
+        } else if (std.mem.startsWith(u8, fmt, "%")) {
+            break :blk try custom.render(allocator, weather, fmt);
+        } else {
+            break :blk try line.render(allocator, weather, fmt);
+        }
+    } else try ansi.render(allocator, weather, .{});
 
     const ttl = 1000 + std.crypto.random.intRangeAtMost(u64, 0, 1000);
     try opts.cache.put(cache_key, output, ttl);
 
-    res.content_type = .TEXT;
+    if (res.content_type != .JSON) {
+        res.content_type = .TEXT;
+    }
     res.body = output;
 }
 
diff --git a/zig/src/http/query.zig b/zig/src/http/query.zig
new file mode 100644
index 0000000..0a27c73
--- /dev/null
+++ b/zig/src/http/query.zig
@@ -0,0 +1,88 @@
+const std = @import("std");
+
+pub const QueryParams = struct {
+    format: ?[]const u8 = null,
+    lang: ?[]const u8 = null,
+    units: ?Units = null,
+    transparency: ?u8 = null,
+
+    pub const Units = enum {
+        metric,
+        uscs,
+    };
+
+    pub fn parse(allocator: std.mem.Allocator, query_string: []const u8) !QueryParams {
+        var params = QueryParams{};
+        var iter = std.mem.splitScalar(u8, query_string, '&');
+
+        while (iter.next()) |pair| {
+            if (pair.len == 0) continue;
+
+            var kv = std.mem.splitScalar(u8, pair, '=');
+            const key = kv.next() orelse continue;
+            const value = kv.next();
+
+            if (std.mem.eql(u8, key, "format")) {
+                params.format = if (value) |v| try allocator.dupe(u8, v) else null;
+            } else if (std.mem.eql(u8, key, "lang")) {
+                params.lang = if (value) |v| try allocator.dupe(u8, v) else null;
+            } else if (std.mem.eql(u8, key, "u")) {
+                params.units = .uscs;
+            } else if (std.mem.eql(u8, key, "m")) {
+                params.units = .metric;
+            } else if (std.mem.eql(u8, key, "transparency")) {
+                if (value) |v| {
+                    params.transparency = try std.fmt.parseInt(u8, v, 10);
+                }
+            } else if (std.mem.eql(u8, key, "t")) {
+                params.transparency = 150;
+            }
+        }
+
+        return params;
+    }
+};
+
+test "parse empty query" {
+    const allocator = std.testing.allocator;
+    const params = try QueryParams.parse(allocator, "");
+    try std.testing.expect(params.format == null);
+    try std.testing.expect(params.lang == null);
+    try std.testing.expect(params.units == null);
+}
+
+test "parse format parameter" {
+    const allocator = std.testing.allocator;
+    const params = try QueryParams.parse(allocator, "format=j1");
+    defer if (params.format) |f| allocator.free(f);
+    try std.testing.expect(params.format != null);
+    try std.testing.expectEqualStrings("j1", params.format.?);
+}
+
+test "parse units parameters" {
+    const allocator = std.testing.allocator;
+    const params_m = try QueryParams.parse(allocator, "m");
+    try std.testing.expectEqual(QueryParams.Units.metric, params_m.units.?);
+
+    const params_u = try QueryParams.parse(allocator, "u");
+    try std.testing.expectEqual(QueryParams.Units.uscs, params_u.units.?);
+}
+
+test "parse multiple parameters" {
+    const allocator = std.testing.allocator;
+    const params = try QueryParams.parse(allocator, "format=3&lang=de&m");
+    defer if (params.format) |f| allocator.free(f);
+    defer if (params.lang) |l| allocator.free(l);
+    try std.testing.expectEqualStrings("3", params.format.?);
+    try std.testing.expectEqualStrings("de", params.lang.?);
+    try std.testing.expectEqual(QueryParams.Units.metric, params.units.?);
+}
+
+test "parse transparency" {
+    const allocator = std.testing.allocator;
+    const params_t = try QueryParams.parse(allocator, "t");
+    try std.testing.expectEqual(@as(u8, 150), params_t.transparency.?);
+
+    const params_custom = try QueryParams.parse(allocator, "transparency=200");
+    try std.testing.expectEqual(@as(u8, 200), params_custom.transparency.?);
+}
diff --git a/zig/src/location/resolver.zig b/zig/src/location/resolver.zig
index 6eb2745..1a165cc 100644
--- a/zig/src/location/resolver.zig
+++ b/zig/src/location/resolver.zig
@@ -74,7 +74,7 @@ pub const Resolver = struct {
         }
 
         // Format IP address
-        const ip_str = try std.fmt.allocPrint(self.allocator, "{}", .{addr_list.addrs[0].any});
+        const ip_str = try std.fmt.allocPrint(self.allocator, "{any}", .{addr_list.addrs[0].any});
         defer self.allocator.free(ip_str);
 
         return self.resolveIP(ip_str);
diff --git a/zig/src/main.zig b/zig/src/main.zig
index e326766..05ca118 100644
--- a/zig/src/main.zig
+++ b/zig/src/main.zig
@@ -70,6 +70,9 @@ test {
     _ = @import("http/query.zig");
     _ = @import("http/help.zig");
     _ = @import("render/line.zig");
+    _ = @import("render/json.zig");
+    _ = @import("render/v2.zig");
+    _ = @import("render/custom.zig");
     _ = @import("location/geoip.zig");
     _ = @import("location/resolver.zig");
 }
diff --git a/zig/src/render/custom.zig b/zig/src/render/custom.zig
new file mode 100644
index 0000000..b591d8f
--- /dev/null
+++ b/zig/src/render/custom.zig
@@ -0,0 +1,137 @@
+const std = @import("std");
+const types = @import("../weather/types.zig");
+
+const weather_icons = [_][]const u8{
+    "✨", // 0-99
+    "🌑", // 100-199
+    "⛅", // 200-299
+    "☁️", // 300-399
+};
+
+fn getWeatherIcon(code: u16) []const u8 {
+    const idx = @min(code / 100, weather_icons.len - 1);
+    return weather_icons[idx];
+}
+
+pub fn render(allocator: std.mem.Allocator, weather: types.WeatherData, format: []const u8) ![]const u8 {
+    var output: std.ArrayList(u8) = .empty;
+    errdefer output.deinit(allocator);
+    const writer = output.writer(allocator);
+
+    var i: usize = 0;
+    while (i < format.len) {
+        if (format[i] == '%' and i + 1 < format.len) {
+            const code = format[i + 1];
+            switch (code) {
+                'c' => try writer.print("{s}", .{getWeatherIcon(weather.current.weather_code)}),
+                'C' => try writer.print("{s}", .{weather.current.condition}),
+                'h' => try writer.print("{d}%", .{weather.current.humidity}),
+                't' => try writer.print("{d:.0}°C", .{weather.current.temp_c}),
+                'f' => try writer.print("{d:.0}°C", .{weather.current.temp_c}), // Feels like (same as temp for now)
+                'w' => try writer.print("{d:.0} km/h {s}", .{ weather.current.wind_kph, weather.current.wind_dir }),
+                'l' => try writer.print("{s}", .{weather.location}),
+                'p' => try writer.print("{d:.1} mm", .{weather.current.precip_mm}),
+                'P' => try writer.print("{d:.0} hPa", .{weather.current.pressure_mb}),
+                'm' => try writer.print("🌕", .{}), // Moon phase placeholder
+                'M' => try writer.print("15", .{}), // Moon day placeholder
+                'o' => try writer.print("0%", .{}), // Probability of precipitation placeholder
+                'D' => try writer.print("06:00", .{}), // Dawn placeholder
+                'S' => try writer.print("07:30", .{}), // Sunrise placeholder
+                'z' => try writer.print("12:00", .{}), // Zenith placeholder
+                's' => try writer.print("18:30", .{}), // Sunset placeholder
+                'd' => try writer.print("20:00", .{}), // Dusk placeholder
+                '%' => try writer.print("%", .{}),
+                'n' => try writer.print("\n", .{}),
+                else => {
+                    try writer.print("%{c}", .{code});
+                },
+            }
+            i += 2;
+        } else {
+            try writer.writeByte(format[i]);
+            i += 1;
+        }
+    }
+
+    return output.toOwnedSlice(allocator);
+}
+
+test "render custom format with location and temp" {
+    const allocator = std.testing.allocator;
+
+    const weather = types.WeatherData{
+        .location = "London",
+        .current = .{
+            .temp_c = 7.0,
+            .temp_f = 44.6,
+            .condition = "Overcast",
+            .weather_code = 122,
+            .humidity = 76,
+            .wind_kph = 11.0,
+            .wind_dir = "NNE",
+            .pressure_mb = 1019.0,
+            .precip_mm = 0.0,
+        },
+        .forecast = &[_]types.ForecastDay{},
+        .allocator = allocator,
+    };
+
+    const output = try render(allocator, weather, "%l: %c %t");
+    defer allocator.free(output);
+
+    try std.testing.expect(std.mem.indexOf(u8, output, "London") != null);
+    try std.testing.expect(std.mem.indexOf(u8, output, "7°C") != null);
+}
+
+test "render custom format with newline" {
+    const allocator = std.testing.allocator;
+
+    const weather = types.WeatherData{
+        .location = "Paris",
+        .current = .{
+            .temp_c = 10.0,
+            .temp_f = 50.0,
+            .condition = "Clear",
+            .weather_code = 113,
+            .humidity = 65,
+            .wind_kph = 8.0,
+            .wind_dir = "E",
+            .pressure_mb = 1020.0,
+            .precip_mm = 0.0,
+        },
+        .forecast = &[_]types.ForecastDay{},
+        .allocator = allocator,
+    };
+
+    const output = try render(allocator, weather, "%l%n%C");
+    defer allocator.free(output);
+
+    try std.testing.expect(std.mem.indexOf(u8, output, "Paris\nClear") != null);
+}
+
+test "render custom format with humidity and pressure" {
+    const allocator = std.testing.allocator;
+
+    const weather = types.WeatherData{
+        .location = "Berlin",
+        .current = .{
+            .temp_c = 5.0,
+            .temp_f = 41.0,
+            .condition = "Cloudy",
+            .weather_code = 119,
+            .humidity = 85,
+            .wind_kph = 12.0,
+            .wind_dir = "W",
+            .pressure_mb = 1012.0,
+            .precip_mm = 0.2,
+        },
+        .forecast = &[_]types.ForecastDay{},
+        .allocator = allocator,
+    };
+
+    const output = try render(allocator, weather, "Humidity: %h, Pressure: %P");
+    defer allocator.free(output);
+
+    try std.testing.expect(std.mem.indexOf(u8, output, "85%") != null);
+    try std.testing.expect(std.mem.indexOf(u8, output, "1012") != null);
+}
diff --git a/zig/src/render/json.zig b/zig/src/render/json.zig
index 163be80..23ef0d9 100644
--- a/zig/src/render/json.zig
+++ b/zig/src/render/json.zig
@@ -2,10 +2,7 @@ const std = @import("std");
 const types = @import("../weather/types.zig");
 
 pub fn render(allocator: std.mem.Allocator, weather: types.WeatherData) ![]const u8 {
-    var output = std.ArrayList(u8).init(allocator);
-    errdefer output.deinit();
-
-    try std.json.stringify(.{
+    const data = .{
         .current_condition = .{
             .temp_C = weather.current.temp_c,
             .temp_F = weather.current.temp_f,
@@ -17,31 +14,10 @@ pub fn render(allocator: std.mem.Allocator, weather: types.WeatherData) ![]const
             .pressure = weather.current.pressure_mb,
             .precipMM = weather.current.precip_mm,
         },
-        .weather = blk: {
-            var forecast_array = std.ArrayList(struct {
-                date: []const u8,
-                maxtempC: f32,
-                mintempC: f32,
-                weatherCode: u16,
-                weatherDesc: []const u8,
-            }).init(allocator);
-            defer forecast_array.deinit();
+        .weather = weather.forecast,
+    };
 
-            for (weather.forecast) |day| {
-                try forecast_array.append(.{
-                    .date = day.date,
-                    .maxtempC = day.max_temp_c,
-                    .mintempC = day.min_temp_c,
-                    .weatherCode = day.weather_code,
-                    .weatherDesc = day.condition,
-                });
-            }
-
-            break :blk try forecast_array.toOwnedSlice();
-        },
-    }, .{}, output.writer());
-
-    return output.toOwnedSlice();
+    return try std.fmt.allocPrint(allocator, "{any}", .{std.json.fmt(data, .{})});
 }
 
 test "render json format" {
diff --git a/zig/src/render/line.zig b/zig/src/render/line.zig
index c12a170..10aa141 100644
--- a/zig/src/render/line.zig
+++ b/zig/src/render/line.zig
@@ -9,30 +9,36 @@ pub fn render(allocator: std.mem.Allocator, data: types.WeatherData, format: []c
             data.current.temp_c,
         });
     } else if (std.mem.eql(u8, format, "2")) {
-        return std.fmt.allocPrint(allocator, "{s}: {s} {d:.0}°C 🌬️{s}{d:.0}km/h", .{
+        return std.fmt.allocPrint(allocator, "{s}: {s} {d:.0}°C {s}{s}{d:.0}km/h", .{
             data.location,
             getConditionEmoji(data.current.weather_code),
             data.current.temp_c,
+            "🌬️",
             data.current.wind_dir,
             data.current.wind_kph,
         });
     } else if (std.mem.eql(u8, format, "3")) {
-        return std.fmt.allocPrint(allocator, "{s}: {s} {d:.0}°C 🌬️{s}{d:.0}km/h 💧{d}%%", .{
+        return std.fmt.allocPrint(allocator, "{s}: {s} {d:.0}°C {s}{s}{d:.0}km/h {s}{d}%%", .{
             data.location,
             getConditionEmoji(data.current.weather_code),
             data.current.temp_c,
+            "🌬️",
             data.current.wind_dir,
             data.current.wind_kph,
+            "💧",
             data.current.humidity,
         });
     } else if (std.mem.eql(u8, format, "4")) {
-        return std.fmt.allocPrint(allocator, "{s}: {s} {d:.0}°C 🌬️{s}{d:.0}km/h 💧{d}%% ☀️", .{
+        return std.fmt.allocPrint(allocator, "{s}: {s} {d:.0}°C {s}{s}{d:.0}km/h {s}{d}%% {s}", .{
             data.location,
             getConditionEmoji(data.current.weather_code),
             data.current.temp_c,
+            "🌬️",
             data.current.wind_dir,
             data.current.wind_kph,
+            "💧",
             data.current.humidity,
+            "☀️",
         });
     } else {
         return renderCustom(allocator, data, format);
diff --git a/zig/src/render/v2.zig b/zig/src/render/v2.zig
new file mode 100644
index 0000000..98216ca
--- /dev/null
+++ b/zig/src/render/v2.zig
@@ -0,0 +1,68 @@
+const std = @import("std");
+const types = @import("../weather/types.zig");
+
+pub fn render(allocator: std.mem.Allocator, weather: types.WeatherData) ![]const u8 {
+    var output: std.ArrayList(u8) = .empty;
+    errdefer output.deinit(allocator);
+    const writer = output.writer(allocator);
+
+    // Header with location
+    try writer.print("Weather report: {s}\n\n", .{weather.location});
+
+    // Current conditions
+    try writer.print("      Current conditions\n", .{});
+    try writer.print("      {s}\n", .{weather.current.condition});
+    try writer.writeAll("      🌡️  ");
+    try writer.print("{d:.1}°C ({d:.1}°F)\n", .{ weather.current.temp_c, weather.current.temp_f });
+    try writer.writeAll("      💧 ");
+    try writer.print("{d}%\n", .{weather.current.humidity});
+    try writer.writeAll("      🌬️  ");
+    try writer.print("{d:.1} km/h {s}\n", .{ weather.current.wind_kph, weather.current.wind_dir });
+    try writer.writeAll("      🔽 ");
+    try writer.print("{d:.1} hPa\n", .{weather.current.pressure_mb});
+    try writer.writeAll("      💦 ");
+    try writer.print("{d:.1} mm\n\n", .{weather.current.precip_mm});
+
+    // Forecast
+    if (weather.forecast.len > 0) {
+        try writer.print("      Forecast\n", .{});
+        for (weather.forecast) |day| {
+            try writer.print("      {s}: {s}\n", .{ day.date, day.condition });
+            try writer.writeAll("      ↑ ");
+            try writer.print("{d:.1}°C  ", .{day.max_temp_c});
+            try writer.writeAll("↓ ");
+            try writer.print("{d:.1}°C\n", .{day.min_temp_c});
+        }
+    }
+
+    return output.toOwnedSlice(allocator);
+}
+
+test "render v2 format" {
+    const allocator = std.testing.allocator;
+
+    const weather = types.WeatherData{
+        .location = "Munich",
+        .current = .{
+            .temp_c = 12.0,
+            .temp_f = 53.6,
+            .condition = "Overcast",
+            .weather_code = 122,
+            .humidity = 80,
+            .wind_kph = 15.0,
+            .wind_dir = "NW",
+            .pressure_mb = 1015.0,
+            .precip_mm = 0.5,
+        },
+        .forecast = &[_]types.ForecastDay{},
+        .allocator = allocator,
+    };
+
+    const output = try render(allocator, weather);
+    defer allocator.free(output);
+
+    try std.testing.expect(output.len > 0);
+    try std.testing.expect(std.mem.indexOf(u8, output, "Munich") != null);
+    try std.testing.expect(std.mem.indexOf(u8, output, "Current conditions") != null);
+    try std.testing.expect(std.mem.indexOf(u8, output, "12.0°C") != null);
+}