diff --git a/TypeScript/filter.ts b/TypeScript/filter.ts
new file mode 100644
index 0000000..6ff000d
--- /dev/null
+++ b/TypeScript/filter.ts
@@ -0,0 +1,638 @@
+import {
+  CommandControlPlugin,
+  type CommandType,
+  type Context,
+  controller,
+} from "@sern/handler";
+import {
+  GuildMember,
+  GuildMemberRoleManager,
+  PermissionResolvable,
+  PermissionsBitField,
+  User,
+} from "discord.js";
+
+
+export type Test = (context: Context) => boolean;
+
+export class Criteria {
+  public constructor(
+    public readonly name: string,
+    public readonly execute: Test,
+    public readonly children: Array<Criteria>
+  ) {}
+  toString() {
+    return this.name + ' ' + this.children.map(c => c.name).join(', ')
+  }
+}
+
+export const or = (...filters: Array<FilterImpl>): FilterImpl => {
+    function execute(context: Context): boolean {
+      let pass = false;
+      tests: for (const filter of filters) {
+        if (filter.test(context)) {
+          pass = true;
+          break tests;
+        }
+      }
+
+      return pass;
+    }
+
+    const children: Array<Criteria> = filters.map((x) => x.criteria);
+
+    return new FilterImpl(
+      new Criteria("or", execute, children),
+      `or(${filters.map((x) => x.message).join(", ")})`
+    );
+}
+
+
+export const and = (...filters: Array<FilterImpl>): FilterImpl => {
+    function execute(context: Context): boolean {
+      for (const filter of filters) {
+        if (!filter.test(context)) {
+          return false;
+        }
+      }
+
+      return true;
+    }
+
+    const children: Array<Criteria> = filters.map((x) => x.criteria);
+
+    return new FilterImpl(
+      new Criteria("and", execute, children),
+      `and(${filters.map((x) => x.message).join(", ")})`
+    );
+
+}
+
+
+export const not = (filter: FilterImpl): FilterImpl => {
+    function execute(context: Context): boolean {
+      return !filter.test(context);
+    }
+
+    return new FilterImpl(
+      new Criteria("not", execute, [filter.criteria]),
+      `not(${filter.criteria})`
+    );
+  }
+export const custom =(execute: Test, message?: string): FilterImpl => {
+    return new FilterImpl(new Criteria("custom", execute, []), message);
+}
+
+export const withCustomMessage = (
+    filter: FilterImpl,
+    message?: string
+): FilterImpl => {
+    return new FilterImpl(filter.criteria, message);
+}
+
+export const hasGuildPermission = (
+    permission: PermissionResolvable
+): FilterImpl => {
+    const b = PermissionsBitField.resolve(permission);
+    const field = Object.entries(PermissionsBitField.Flags).find(
+      ([, v]) => v === b
+    );
+
+    if (field === undefined) {
+      throw new Error(
+        `unknown permission \`${permission}\` in filter \`hasGuildPermission\``
+      );
+    }
+
+    const [name] = field;
+
+    function execute(context: Context): boolean {
+      if (context.member !== null) {
+        if (typeof context.member.permissions === "string") {
+          return new PermissionsBitField(BigInt(context.member.permissions)).has(b);
+        }
+        return context.member.permissions.has(b);
+      }
+
+      return true;
+    }
+
+    return new FilterImpl(
+      new Criteria("hasGuildPermission", execute, []),
+      `has guild permission: ${name}`
+    );
+}
+export const hasChannelPermission = (
+    permission: PermissionResolvable,
+    channelId?: string
+  ): FilterImpl => {
+    const b = PermissionsBitField.resolve(permission);
+    const field = Object.entries(PermissionsBitField.Flags).find(
+      ([, v]) => v === b
+    );
+
+    if (field === undefined) {
+      throw new Error(
+        `unknown permission \`${permission}\` in filter \`hasChannelPermission\``
+      );
+    }
+
+    const [name] = field;
+
+    function execute(context: Context): boolean {
+      if (context.member !== null) {
+        const channel =
+          channelId !== undefined
+            ? context.guild?.channels.cache.get(channelId)
+            : context.channel;
+
+        // ?
+        if (channel == undefined || channel === null) {
+          return false;
+        }
+
+        if (channel.isDMBased()) {
+          return true;
+        }
+
+        const field2 = channel.permissionsFor(context.user);
+
+        // assume we have no permission overrides
+        if (field2 === null) {
+          if (context.member !== null) {
+            if (typeof context.member.permissions === "string") {
+              return new PermissionsBitField(
+                BigInt(context.member.permissions)
+              ).has(b);
+            }
+
+            return context.member.permissions.has(b);
+          }
+
+          return false;
+        }
+
+        return field2.has(b);
+      }
+
+      return true;
+    }
+
+    return new FilterImpl(
+      new Criteria("hasChannelPermission", execute, []),
+      channelId !== undefined
+        ? `has channel permission ${name} in <#${channelId}>`
+        : `has channel permission ${name}`
+    );
+  }
+
+export const canAddReactions =(channelId?: string): FilterImpl => {
+    return hasChannelPermission("AddReactions", channelId);
+}
+
+export const canAttachFiles =(channelId?: string): FilterImpl => {
+    return hasChannelPermission("AttachFiles", channelId);
+}
+
+export const canBanMembers = (): FilterImpl => {
+    return hasGuildPermission("BanMembers");
+}
+
+export const canChangeNickname = (): FilterImpl => {
+    return hasGuildPermission("ChangeNickname");
+}
+
+export const canConnect = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("Connect", channelId);
+}
+
+export const canCreateInstantInvite =(channelId?: string): FilterImpl => {
+    return hasChannelPermission("CreateInstantInvite", channelId);
+  }
+
+export const canDeafenMembers =(channelId?: string): FilterImpl => {
+    return hasChannelPermission("DeafenMembers", channelId);
+  }
+
+export const canEmbedLinks =(channelId?: string): FilterImpl => {
+    return hasChannelPermission("EmbedLinks", channelId);
+  }
+
+export const canKickMembers =(): FilterImpl => {
+    return hasGuildPermission("KickMembers");
+  }
+
+export const canManageChannelWebhooks =(channelId?: string): FilterImpl => {
+    return hasChannelPermission("ManageWebhooks", channelId);
+  }
+
+export const canManageChannels =(channelId?: string): FilterImpl => {
+    return hasChannelPermission("ManageChannels", channelId);
+}
+
+export const canManageEmojisAndStickers =(): FilterImpl => {
+    return hasGuildPermission("ManageEmojisAndStickers");
+}
+
+export const canManageGuild =(): FilterImpl => {
+    return hasGuildPermission("ManageGuild");
+}
+
+export const canManageGuildWebhooks =(): FilterImpl => {
+    return hasGuildPermission("ManageWebhooks");
+}
+
+export const canManageMessages =(channelId?: string): FilterImpl => {
+    return hasChannelPermission("ManageMessages", channelId);
+}
+
+export const canManageNicknames = (): FilterImpl => {
+    return hasGuildPermission("ManageNicknames");
+}
+
+export const canManageRoles = (): FilterImpl => {
+    return hasGuildPermission("ManageRoles");
+}
+
+export const canMentionEveryone = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("MentionEveryone", channelId);
+  }
+
+export const canMoveMembers = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("MoveMembers", channelId);
+  }
+
+export const canMuteMembers = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("MuteMembers", channelId);
+  }
+
+export const canPrioritySpeaker = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("PrioritySpeaker", channelId);
+  }
+
+export const canReadMessageHistory = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("ReadMessageHistory", channelId);
+  }
+
+export const canViewChannel = (channelId: string): FilterImpl => {
+    return hasChannelPermission("ViewChannel", channelId);
+  }
+
+export const canSendMessages = (channelId: string): FilterImpl => {
+    return hasChannelPermission("SendMessages", channelId);
+  }
+
+export const canSendTtsMessages = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("SendTTSMessages", channelId);
+  }
+
+export const canSpeak = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("Speak", channelId);
+  }
+
+export const canStream = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("Stream", channelId);
+  }
+
+export const canUseExternalEmojis = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("UseExternalEmojis", channelId);
+  }
+
+export const canUseVoiceActivity = (channelId?: string): FilterImpl => {
+    return hasChannelPermission("UseVAD", channelId);
+  }
+
+export const canViewAuditLog = (): FilterImpl => {
+    return hasGuildPermission("ViewAuditLog");
+  }
+
+export const canViewGuildInsights = (): FilterImpl => {
+    return hasGuildPermission("ViewGuildInsights");
+  }
+
+export const channelIdIn = (channelIds: Array<string>): FilterImpl => {
+    function execute(context: Context): boolean {
+      return channelIds.includes(
+        context.isMessage()
+          ? context.message.channelId
+          : context.interaction.channelId
+      );
+    }
+
+    return new FilterImpl(
+      new Criteria("channelIdIn", execute, []),
+      `channel is one of: ${channelIds.map((v) => `<#${v}>`).join(", ")}`
+    );
+  }
+
+export const hasEveryRole = (roles: Array<string>): FilterImpl => {
+    return withCustomMessage(
+      and(...roles.map((v) => hasRole(v))),
+      `has all of: ${roles.map((v) => `<@&${v}>`).join(", ")}`
+    );
+  }
+
+export const hasMentionableRole = (): FilterImpl => {
+    function execute(context: Context): boolean {
+      if (context.member !== null) {
+        if (context.member.roles instanceof GuildMemberRoleManager) {
+          return (
+            context.member.roles.cache.filter((x) => x.mentionable === true)
+              .size > 0
+          );
+        }
+
+        if (context.guild === null) {
+          return false;
+        }
+
+        return context.member.roles
+          .map((roleId) => context.guild!.roles.cache.get(roleId))
+          .filter((x) => x !== undefined)
+          .some((x) => x!.mentionable);
+      }
+
+      return false;
+    }
+    return new FilterImpl(
+      new Criteria("hasMentionableRole", execute, []),
+      "has a mentionable role"
+    );
+  }
+
+export const hasNickname = (nickname?: string): FilterImpl => {
+    function execute(context: Context): boolean {
+      if (context.member !== null) {
+        if (context.member instanceof GuildMember) {
+          if (nickname !== null) {
+            return context.member.nickname === nickname;
+          }
+
+          return context.member.nickname !== null;
+        }
+
+        if (nickname !== null) {
+          return context.member.nick === nickname;
+        }
+
+        return (
+          context.member.nick !== null && context.member.nick !== undefined
+        );
+      }
+
+      // dm members can technically have nicknames but they're per-user, so this should never be true.
+      return false;
+    }
+    return new FilterImpl(new Criteria("hasNickname", execute, []), "has a nickname");
+  }
+
+export const hasParentId = (parentId: string): FilterImpl => {
+    function execute(context: Context): boolean {
+      if (context.channel !== null) {
+        if (context.channel.isDMBased()) {
+          return false;
+        }
+
+        return context.channel.parentId === parentId;
+      }
+
+      return false;
+    }
+
+    return new FilterImpl(
+      new Criteria("hasParentId", execute, []),
+      `has channel parent <#${parentId}>`
+    );
+  }
+
+export const hasRole = (roleId: string): FilterImpl => {
+    function execute(context: Context): boolean {
+      if (context.member !== null) {
+        if (context.member.roles instanceof GuildMemberRoleManager) {
+          return context.member.roles.cache.has(roleId);
+        }
+
+        if (context.guild === null) {
+          return false;
+        }
+
+        return context.member.roles.includes(roleId);
+      }
+
+      // assume dm members have every role ever.
+      return true;
+    }
+
+    return new FilterImpl(
+      new Criteria("hasRole", execute, []),
+      `has role <@&${roleId}>`
+    );
+  }
+
+export const hasSomeRole = (roles: Array<string>): FilterImpl => {
+    return withCustomMessage(
+      or(...roles.map((role) => hasRole(role))),
+      `has any of: ${roles.map((v) => `<@&${v}>`).join(", ")}`
+    );
+  }
+
+export const isAdministator = (): FilterImpl => {
+    return hasGuildPermission("Administrator");
+  }
+
+export const isChannelId = (channelId: string): FilterImpl => {
+    function execute(context: Context): boolean {
+      if (context.isMessage()) {
+        return context.message.channelId === channelId;
+      }
+
+      return context.interaction.channelId === channelId;
+    }
+
+    return new FilterImpl(
+      new Criteria("isChannelId", execute, []),
+      `is channel <#${channelId}>`
+    );
+  }
+
+export const isChannelNsfw = (): FilterImpl => {
+    function execute(context: Context): boolean {
+      if (context.channel !== null) {
+        if (context.channel.isDMBased() || context.channel.isThread()) {
+          return false;
+        }
+
+        return context.channel.nsfw;
+      }
+
+      return false;
+    }
+    return new FilterImpl(
+      new Criteria("isChannelNsfw", execute, []),
+      "channel marked as nsfw"
+    );
+  }
+
+export const isGuildOwner = (): FilterImpl => {
+    function execute(context: Context): boolean {
+      if (context.guild !== null) {
+        return context.guild.ownerId === context.user.id;
+      }
+
+      return true;
+    }
+    return new FilterImpl(
+      new Criteria("isGuildOwner", execute, []),
+      "is guild owner"
+    );
+  }
+
+export const isBotOwner = (): FilterImpl => {
+    function execute(context: Context): boolean {
+      if (context.client.application !== null) {
+        if (context.client.application.owner !== null) {
+          if (context.client.application.owner instanceof User) {
+            return context.user.id === context.client.application.owner.id;
+          }
+
+          return context.client.application.owner.members.has(context.user.id);
+        }
+      }
+
+      // nope
+      return false;
+    }
+    return new FilterImpl(new Criteria("isBotOwner", execute, []), "is bot owner");
+  }
+
+export const isUserId = (userId: string): FilterImpl => {
+    function execute(context: Context): boolean {
+      return context.user.id === userId;
+    }
+    return new FilterImpl(
+      new Criteria("isUserId", execute, []),
+      `is user: <@${userId}>`
+    );
+  }
+
+export const parentIdIn = (parentIds: Array<string>): FilterImpl => {
+    return withCustomMessage(
+      or(...parentIds.map((v) => hasParentId(v))),
+      `channel parent is one of: ${parentIds.map((v) => `<#${v}>`).join(", ")}`
+    );
+  }
+
+export const userIdIn = (userIds: Array<string>): FilterImpl => {
+    return withCustomMessage(
+      or(...userIds.map((v) => isUserId(v))),
+      `user is one of: ${userIds.map((v) => `<@${v}>`).join(", ")}`
+    );
+  }
+
+export const isInGuild = (): FilterImpl => {
+    function execute(context: Context): boolean {
+      return context.guildId !== null;
+    }
+
+    return new FilterImpl(new Criteria("isInGuild", execute, []), "is in guild");
+  }
+
+export const isInDm = (): FilterImpl => {
+    const notInGuild = compose(not, isInGuild);
+    return withCustomMessage(notInGuild(), "is in dm");
+}
+
+export const never = (): FilterImpl => {
+    function execute(context: Context): boolean {
+      void context;
+      return false;
+    }
+    return new FilterImpl(new Criteria("never", execute, []), "never");
+}
+
+export const always = (): FilterImpl => {
+    function execute(context: Context): boolean {
+      void context;
+      return true;
+    }
+    return new FilterImpl(new Criteria("always", execute, []), "always");
+}
+type CtxMap<T> = (arg: T) => FilterImpl;
+
+/**
+  * Call FilterImpls in right to left order. 
+  * @example 
+  * import { compose, isUserId, not } from '../plugins/filter'
+  * const isNotUserId = compose(not, isUserId)
+  *
+  */
+export const compose = <T = void>(...funcs: CtxMap<any>[]): CtxMap<T> => {
+    return (arg: T): FilterImpl => 
+        //@ts-ignore
+        funcs.reduceRight((result, func) => func(result), arg);
+}
+
+
+export class FilterImpl {
+  public readonly test: Test;
+
+  public constructor(
+    public readonly criteria: Criteria,
+    public message?: string
+  ) {
+    this.test = this.criteria.execute;
+  }
+}
+
+
+export type FilterOptions = {
+  condition: Array<FilterImpl> | FilterImpl,
+  onFailed?: (context: Context, filters: Array<FilterImpl>) => unknown
+};
+/**
+ * @plugin
+ * Generalized `filter` plugin. revised by jacoobes, all credit to original author.
+ * Perform declarative conditionals as plugins.  
+ * @author @trueharuu [<@504698587221852172>]
+ * @version 2.0.0
+ * @example 
+ * import { filter, not, isGuildOwner, canMentionEveryone } from '../plugins/filter';
+ * import { commandModule } from '@sern/handler';
+ *
+ * export default commandModule({
+ *     plugins: [filter({ condition: [not(isGuildOwner()), canMentionEveryone()] })],
+ *     async execute(context) {
+ *       // your code here
+ *     }
+ * });
+ */
+
+export const filter = 
+  (options: FilterOptions) => {
+    return CommandControlPlugin<CommandType.Both>(async (context) => {
+      const arrayifiedCondition = Array.isArray(options.condition) ? options.condition : [options.condition]
+      const value = and(...arrayifiedCondition).test(context);
+
+      if (value) {
+        return controller.next();
+      }
+
+      if (options.onFailed !== undefined) {
+        await options.onFailed(context, arrayifiedCondition);
+      } else {
+        await context.reply({
+          ephemeral: true,
+          content: `you do not match the criteria for this command:\n${arrayifiedCondition
+            .map((x) => x.message)
+            .filter((x) => x !== undefined)
+            .join("\n")}`,
+          allowedMentions: {
+            repliedUser: false,
+            parse: [],
+          },
+        });
+      }
+
+      return controller.stop();
+    });
+  };