diff --git a/PluralKit.API/Controllers/v2/GuildControllerV2.cs b/PluralKit.API/Controllers/v2/GuildControllerV2.cs
index ed0631cb..e3abd0de 100644
--- a/PluralKit.API/Controllers/v2/GuildControllerV2.cs
+++ b/PluralKit.API/Controllers/v2/GuildControllerV2.cs
@@ -17,40 +17,119 @@ namespace PluralKit.API
         public GuildControllerV2(IServiceProvider svc) : base(svc) { }
 
 
-        [HttpGet("systems/{system}/guilds/{guild_id}")]
-        public async Task<IActionResult> SystemGuildGet(string system, ulong guild_id)
+        [HttpGet("systems/@me/guilds/{guild_id}")]
+        public async Task<IActionResult> SystemGuildGet(ulong guild_id)
         {
-            return new ObjectResult("Unimplemented")
-            {
-                StatusCode = 501
-            };
+            var system = await ResolveSystem("@me");
+            var settings = await _repo.GetSystemGuild(guild_id, system.Id, defaultInsert: false);
+            if (settings == null)
+                throw APIErrors.SystemGuildNotFound;
+
+            PKMember member = null;
+            if (settings.AutoproxyMember != null)
+                member = await _repo.GetMember(settings.AutoproxyMember.Value);
+
+            return Ok(settings.ToJson(member?.Hid));
         }
 
-        [HttpPatch("systems/{system}/guilds/{guild_id}")]
-        public async Task<IActionResult> SystemGuildPatch(string system, ulong guild_id, [FromBody] JObject data)
+        [HttpPatch("systems/@me/guilds/{guild_id}")]
+        public async Task<IActionResult> DoSystemGuildPatch(ulong guild_id, [FromBody] JObject data)
         {
-            return new ObjectResult("Unimplemented")
+            var system = await ResolveSystem("@me");
+            var settings = await _repo.GetSystemGuild(guild_id, system.Id, defaultInsert: false);
+            if (settings == null)
+                throw APIErrors.SystemGuildNotFound;
+
+            MemberId? memberId = null;
+            if (data.ContainsKey("autoproxy_member"))
             {
-                StatusCode = 501
-            };
+                if (data["autoproxy_member"].Type != JTokenType.Null)
+                {
+                    var member = await ResolveMember(data.Value<string>("autoproxy_member"));
+                    if (member == null)
+                        throw APIErrors.MemberNotFound;
+
+                    memberId = member.Id;
+                }
+            }
+            else
+                memberId = settings.AutoproxyMember;
+
+            SystemGuildPatch patch = null;
+            try
+            {
+                patch = SystemGuildPatch.FromJson(data, memberId);
+                patch.AssertIsValid();
+            }
+            catch (ValidationError e)
+            {
+                // todo
+                return BadRequest(e.Message);
+            }
+
+            // this is less than great, but at least it's legible
+            if (patch.AutoproxyMember.Value == null)
+                if (patch.AutoproxyMode.IsPresent)
+                {
+                    if (patch.AutoproxyMode.Value == AutoproxyMode.Member)
+                        throw APIErrors.MissingAutoproxyMember;
+                }
+                else if (settings.AutoproxyMode == AutoproxyMode.Member)
+                    throw APIErrors.MissingAutoproxyMember;
+
+            var newSettings = await _repo.UpdateSystemGuild(system.Id, guild_id, patch);
+
+            PKMember? newMember = null;
+            if (newSettings.AutoproxyMember != null)
+                newMember = await _repo.GetMember(newSettings.AutoproxyMember.Value);
+            return Ok(newSettings.ToJson(newMember?.Hid));
         }
 
-        [HttpGet("members/{member}/guilds/{guild_id}")]
-        public async Task<IActionResult> MemberGuildGet(string member, ulong guild_id)
+        [HttpGet("members/{memberRef}/guilds/{guild_id}")]
+        public async Task<IActionResult> MemberGuildGet(string memberRef, ulong guild_id)
         {
-            return new ObjectResult("Unimplemented")
-            {
-                StatusCode = 501
-            };
+            var system = await ResolveSystem("@me");
+            var member = await ResolveMember(memberRef);
+            if (member == null)
+                throw APIErrors.MemberNotFound;
+            if (member.System != system.Id)
+                throw APIErrors.NotOwnMemberError;
+
+            var settings = await _repo.GetMemberGuild(guild_id, member.Id, defaultInsert: false);
+            if (settings == null)
+                throw APIErrors.MemberGuildNotFound;
+
+            return Ok(settings.ToJson());
         }
 
-        [HttpPatch("members/{member}/guilds/{guild_id}")]
-        public async Task<IActionResult> MemberGuildPatch(string member, ulong guild_id, [FromBody] JObject data)
+        [HttpPatch("members/{memberRef}/guilds/{guild_id}")]
+        public async Task<IActionResult> DoMemberGuildPatch(string memberRef, ulong guild_id, [FromBody] JObject data)
         {
-            return new ObjectResult("Unimplemented")
+            var system = await ResolveSystem("@me");
+            var member = await ResolveMember(memberRef);
+            if (member == null)
+                throw APIErrors.MemberNotFound;
+            if (member.System != system.Id)
+                throw APIErrors.NotOwnMemberError;
+
+            var settings = await _repo.GetMemberGuild(guild_id, member.Id, defaultInsert: false);
+            if (settings == null)
+                throw APIErrors.MemberGuildNotFound;
+
+            MemberGuildPatch patch = null;
+            try
             {
-                StatusCode = 501
-            };
+                patch = MemberGuildPatch.FromJson(data);
+                patch.AssertIsValid();
+            }
+            catch (ValidationError e)
+            {
+                // todo
+                return BadRequest(e.Message);
+            }
+
+            var newSettings = await _repo.UpdateMemberGuild(member.Id, guild_id, patch);
+            return Ok(newSettings.ToJson());
         }
 
 
diff --git a/PluralKit.API/Errors.cs b/PluralKit.API/Errors.cs
index 18d43edc..01b2cd85 100644
--- a/PluralKit.API/Errors.cs
+++ b/PluralKit.API/Errors.cs
@@ -25,7 +25,7 @@ namespace PluralKit.API
 
     public class ModelParseError: PKError
     {
-        public ModelParseError() : base(400, 0, "Error parsing JSON model")
+        public ModelParseError() : base(400, 40001, "Error parsing JSON model")
         {
             // todo
         }
@@ -47,16 +47,19 @@ namespace PluralKit.API
         public static PKError GroupNotFound = new(404, 20003, "Group not found.");
         public static PKError MessageNotFound = new(404, 20004, "Message not found.");
         public static PKError SwitchNotFound = new(404, 20005, "Switch not found, switch is associated to different system, or unauthorized to view front history.");
+        public static PKError SystemGuildNotFound = new(404, 20006, "No system guild settings found for target guild.");
+        public static PKError MemberGuildNotFound = new(404, 20007, "No member guild settings found for target guild.");
         public static PKError UnauthorizedMemberList = new(403, 30001, "Unauthorized to view member list");
         public static PKError UnauthorizedGroupList = new(403, 30002, "Unauthorized to view group list");
         public static PKError UnauthorizedGroupMemberList = new(403, 30003, "Unauthorized to view group member list");
         public static PKError UnauthorizedCurrentFronters = new(403, 30004, "Unauthorized to view current fronters.");
         public static PKError UnauthorizedFrontHistory = new(403, 30005, "Unauthorized to view front history.");
-        public static PKError NotOwnMemberError = new(403, 40001, "Target member is not part of your system.");
-        public static PKError NotOwnGroupError = new(403, 40002, "Target group is not part of your system.");
+        public static PKError NotOwnMemberError = new(403, 30006, "Target member is not part of your system.");
+        public static PKError NotOwnGroupError = new(403, 30006, "Target group is not part of your system.");
         // todo: somehow add the memberRef to the JSON
-        public static PKError NotOwnMemberErrorWithRef(string memberRef) => new(403, 40003, $"Member '{memberRef}' is not part of your system.");
-        public static PKError NotOwnGroupErrorWithRef(string groupRef) => new(403, 40004, $"Group '{groupRef}' is not part of your system.");
+        public static PKError NotOwnMemberErrorWithRef(string memberRef) => new(403, 30008, $"Member '{memberRef}' is not part of your system.");
+        public static PKError NotOwnGroupErrorWithRef(string groupRef) => new(403, 30009, $"Group '{groupRef}' is not part of your system.");
+        public static PKError MissingAutoproxyMember = new(400, 40002, "Missing autoproxy member for member-mode autoproxy.");
         public static PKError Unimplemented = new(501, 50001, "Unimplemented");
     }
 }
\ No newline at end of file
diff --git a/PluralKit.Core/Database/Repository/ModelRepository.Guild.cs b/PluralKit.Core/Database/Repository/ModelRepository.Guild.cs
index 5eb8ed26..851c83d2 100644
--- a/PluralKit.Core/Database/Repository/ModelRepository.Guild.cs
+++ b/PluralKit.Core/Database/Repository/ModelRepository.Guild.cs
@@ -21,8 +21,14 @@ namespace PluralKit.Core
         }
 
 
-        public Task<SystemGuildSettings> GetSystemGuild(ulong guild, SystemId system)
+        public Task<SystemGuildSettings> GetSystemGuild(ulong guild, SystemId system, bool defaultInsert = true)
         {
+            if (!defaultInsert)
+                return _db.QueryFirst<SystemGuildSettings>(new Query("system_guild")
+                    .Where("guild", guild)
+                    .Where("system", system)
+                );
+
             var query = new Query("system_guild").AsInsert(new
             {
                 guild = guild,
@@ -33,16 +39,22 @@ namespace PluralKit.Core
             );
         }
 
-        public Task UpdateSystemGuild(SystemId system, ulong guild, SystemGuildPatch patch)
+        public Task<SystemGuildSettings> UpdateSystemGuild(SystemId system, ulong guild, SystemGuildPatch patch)
         {
             _logger.Information("Updated {SystemId} in guild {GuildId}: {@SystemGuildPatch}", system, guild, patch);
             var query = patch.Apply(new Query("system_guild").Where("system", system).Where("guild", guild));
-            return _db.ExecuteQuery(query, extraSql: "returning *");
+            return _db.QueryFirst<SystemGuildSettings>(query, extraSql: "returning *");
         }
 
 
-        public Task<MemberGuildSettings> GetMemberGuild(ulong guild, MemberId member)
+        public Task<MemberGuildSettings> GetMemberGuild(ulong guild, MemberId member, bool defaultInsert = true)
         {
+            if (!defaultInsert)
+                return _db.QueryFirst<MemberGuildSettings>(new Query("member_guild")
+                    .Where("guild", guild)
+                    .Where("member", member)
+                );
+
             var query = new Query("member_guild").AsInsert(new
             {
                 guild = guild,
@@ -53,11 +65,11 @@ namespace PluralKit.Core
             );
         }
 
-        public Task UpdateMemberGuild(MemberId member, ulong guild, MemberGuildPatch patch)
+        public Task<MemberGuildSettings> UpdateMemberGuild(MemberId member, ulong guild, MemberGuildPatch patch)
         {
             _logger.Information("Updated {MemberId} in guild {GuildId}: {@MemberGuildPatch}", member, guild, patch);
             var query = patch.Apply(new Query("member_guild").Where("member", member).Where("guild", guild));
-            return _db.ExecuteQuery(query, extraSql: "returning *");
+            return _db.QueryFirst<MemberGuildSettings>(query, extraSql: "returning *");
         }
     }
 }
\ No newline at end of file
diff --git a/PluralKit.Core/Models/MemberGuildSettings.cs b/PluralKit.Core/Models/MemberGuildSettings.cs
index 3347275e..db3dfba4 100644
--- a/PluralKit.Core/Models/MemberGuildSettings.cs
+++ b/PluralKit.Core/Models/MemberGuildSettings.cs
@@ -1,3 +1,5 @@
+using Newtonsoft.Json.Linq;
+
 #nullable enable
 namespace PluralKit.Core
 {
@@ -8,4 +10,17 @@ namespace PluralKit.Core
         public string? DisplayName { get; }
         public string? AvatarUrl { get; }
     }
+
+    public static class MemberGuildExt
+    {
+        public static JObject ToJson(this MemberGuildSettings settings)
+        {
+            var o = new JObject();
+
+            o.Add("display_name", settings.DisplayName);
+            o.Add("avatar_url", settings.AvatarUrl);
+
+            return o;
+        }
+    }
 }
\ No newline at end of file
diff --git a/PluralKit.Core/Models/Patch/MemberGuildPatch.cs b/PluralKit.Core/Models/Patch/MemberGuildPatch.cs
index 5207fb7e..7a51df25 100644
--- a/PluralKit.Core/Models/Patch/MemberGuildPatch.cs
+++ b/PluralKit.Core/Models/Patch/MemberGuildPatch.cs
@@ -1,5 +1,7 @@
 #nullable enable
 
+using Newtonsoft.Json.Linq;
+
 using SqlKata;
 
 namespace PluralKit.Core
@@ -13,5 +15,28 @@ namespace PluralKit.Core
             .With("display_name", DisplayName)
             .With("avatar_url", AvatarUrl)
         );
+
+        public new void AssertIsValid()
+        {
+            if (DisplayName.Value != null)
+                AssertValid(DisplayName.Value, "display_name", Limits.MaxMemberNameLength);
+            if (AvatarUrl.Value != null)
+                AssertValid(AvatarUrl.Value, "avatar_url", Limits.MaxUriLength,
+                    s => MiscUtils.TryMatchUri(s, out var avatarUri));
+        }
+
+#nullable disable
+        public static MemberGuildPatch FromJson(JObject o)
+        {
+            var patch = new MemberGuildPatch();
+
+            if (o.ContainsKey("display_name"))
+                patch.DisplayName = o.Value<string>("display_name").NullIfEmpty();
+
+            if (o.ContainsKey("avatar_url"))
+                patch.AvatarUrl = o.Value<string>("avatar_url").NullIfEmpty();
+
+            return patch;
+        }
     }
 }
\ No newline at end of file
diff --git a/PluralKit.Core/Models/Patch/SystemGuildPatch.cs b/PluralKit.Core/Models/Patch/SystemGuildPatch.cs
index a5642f85..241b12d5 100644
--- a/PluralKit.Core/Models/Patch/SystemGuildPatch.cs
+++ b/PluralKit.Core/Models/Patch/SystemGuildPatch.cs
@@ -1,5 +1,7 @@
 #nullable enable
 
+using Newtonsoft.Json.Linq;
+
 using SqlKata;
 
 namespace PluralKit.Core
@@ -19,5 +21,33 @@ namespace PluralKit.Core
             .With("tag", Tag)
             .With("tag_enabled", TagEnabled)
         );
+
+        public new void AssertIsValid()
+        {
+            if (Tag.Value != null)
+                AssertValid(Tag.Value, "tag", Limits.MaxSystemTagLength);
+        }
+
+#nullable disable
+        public static SystemGuildPatch FromJson(JObject o, MemberId? memberId)
+        {
+            var patch = new SystemGuildPatch();
+
+            if (o.ContainsKey("proxying_enabled") && o["proxying_enabled"].Type != JTokenType.Null)
+                patch.ProxyEnabled = o.Value<bool>("proxying_enabled");
+
+            if (o.ContainsKey("autoproxy_mode") && o["autoproxy_mode"].ParseAutoproxyMode() is { } autoproxyMode)
+                patch.AutoproxyMode = autoproxyMode;
+
+            patch.AutoproxyMember = memberId;
+
+            if (o.ContainsKey("tag"))
+                patch.Tag = o.Value<string>("tag").NullIfEmpty();
+
+            if (o.ContainsKey("tag_enabled") && o["tag_enabled"].Type != JTokenType.Null)
+                patch.TagEnabled = o.Value<bool>("tag_enabled");
+
+            return patch;
+        }
     }
 }
\ No newline at end of file
diff --git a/PluralKit.Core/Models/SystemGuildSettings.cs b/PluralKit.Core/Models/SystemGuildSettings.cs
index 83b6a2cd..1d47d15e 100644
--- a/PluralKit.Core/Models/SystemGuildSettings.cs
+++ b/PluralKit.Core/Models/SystemGuildSettings.cs
@@ -1,5 +1,10 @@
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
+using Newtonsoft.Json.Converters;
+
 namespace PluralKit.Core
 {
+    [JsonConverter(typeof(StringEnumConverter))]
     public enum AutoproxyMode
     {
         Off = 1,
@@ -20,4 +25,44 @@ namespace PluralKit.Core
         public string? Tag { get; }
         public bool TagEnabled { get; }
     }
+
+    public static class SystemGuildExt
+    {
+        public static JObject ToJson(this SystemGuildSettings settings, string? memberHid = null)
+        {
+            var o = new JObject();
+
+            o.Add("proxying_enabled", settings.ProxyEnabled);
+            o.Add("autoproxy_mode", settings.AutoproxyMode.ToString().ToLower());
+            o.Add("autoproxy_member", memberHid);
+            o.Add("tag", settings.Tag);
+            o.Add("tag_enabled", settings.TagEnabled);
+
+            return o;
+        }
+
+        public static AutoproxyMode? ParseAutoproxyMode(this JToken o)
+        {
+            if (o.Type == JTokenType.Null)
+                return AutoproxyMode.Off;
+            else if (o.Type != JTokenType.String)
+                return null;
+
+            var value = o.Value<string>();
+
+            switch (value)
+            {
+                case "off":
+                    return AutoproxyMode.Off;
+                case "front":
+                    return AutoproxyMode.Front;
+                case "latch":
+                    return AutoproxyMode.Latch;
+                case "member":
+                    return AutoproxyMode.Member;
+                default:
+                    throw new ValidationError($"Value '{value}' is not a valid autoproxy mode.");
+            }
+        }
+    }
 }
\ No newline at end of file