Core Candy Machine - Guard Groups

On one of the previous pages, we introduced guards and used them to define the access control of our Candy Machines. We’ve seen that using guards, we can for instance add payments of 1 SOL per mint and ensure the mint start after a certain date. But what if we also wanted to charge 2 SOL after a second date? What if we wanted to allow certain token holders to mint for free or at a discounted price?

What if we could define multiple sets of guards that each have their own requirements? For that reason, we’ve created Guard Groups!

How Do Groups Work?

Remember how we can set up guards on any Core Candy Machine by simply providing the settings of the guards we want to enable? Well, Guard Groups work the same way, except you must also give them a unique Label to identify them.

Therefore, each Guard Group has the following attributes:

Label: A unique text identifier. This cannot be longer than 6 characters.
Guards: The settings for all activated guards within that group. This works just like setting up guards directly on the Core Candy Machine.

Let’s take a quick example. Say we wanted to charge 1 SOL from 4 pm to 5 pm and then 2 SOL from 5 pm until the Core Candy Machine is exhausted. All of that whilst making sure we are protected against bots via the Bot Tax guard. Here’s how we could set up our guards:

Group 1:
- Label: “early”
- Guards:
  - Sol Payment: 1 SOL
  - Start Date: 4 pm (ignoring the actual date here for the sake of simplicity)
  - End Date: 5 pm
  - Bot Tax: 0.001 SOL
Group 2:
- Label: “late”
- Guards:
  - Sol Payment: 2 SOL
  - Start Date: 5 pm
  - Bot Tax: 0.001 SOL

And just like that, we’ve created a customized 2-tier minting process!

Now, whenever someone tries to mint from our Core Candy Machine, they will have to explicitly tell us which group they are minting from. Asking for the group label when minting is important because:

It ensures buyers do not experience unexpected minting behaviour. Say we tried to mint for 1 SOL at the very end of the first group’s end date but, by the time the transaction executes, we’re now past that date. If we didn’t ask for the group label, the transaction would succeed and we would be charged 2 SOL even though we expected to only be charged 1 SOL.
It makes it possible to support parallel groups. We’ll talk more about this later on this page.

React Flow

Now let’s see how we can create and update groups using our SDKs.

Create a Candy Machine with guard groups

To create Candy Machines with guard groups, simply provide the groups array to the create function. Each item of this array must contain a label and a guards object containing the settings of all guards we wish to activate in that group.

Here’s how we’d implement the above example using the Umi library.

import { some, sol, dateTime } from '@metaplex-foundation/umi'

await create(umi, {
  // ...
  groups: [
    {
      label: 'early',
      guards: {
        solPayment: some({ lamports: sol(1), destination: treasury }),
        startDate: some({ date: dateTime('2022-10-18T16:00:00Z') }),
        endDate: some({ date: dateTime('2022-10-18T17:00:00Z') }),
        botTax: some({ lamports: sol(0.001), lastInstruction: true }),
      },
    },
    {
      label: 'late',
      guards: {
        solPayment: some({ lamports: sol(2), destination: treasury }),
        startDate: some({ date: dateTime('2022-10-18T17:00:00Z') }),
        botTax: some({ lamports: sol(0.001), lastInstruction: true }),
      },
    },
  ],
}).sendAndConfirm(umi)

To update groups, simply provide that same groups attribute to the updateCandyGuard function. Please note that the entire guards object and groups array will be updated meaning it will override all existing data!

Therefore, make sure to provide the settings for all your groups, even if their settings are not changing. You may want to fetch the latest candy guard account data beforehand to avoid overwriting any existing settings.

Here’s an example, changing the SOL payment guard for the “late” group to 3 SOL instead of 2 SOL.

import { some, sol, dateTime } from '@metaplex-foundation/umi'

const candyGuard = await fetchCandyGuard(umi, candyMachine.mintAuthority)
await updateCandyGuard(umi, {
  candyGuard: candyGuard.publicKey,
  guards: candyGuard.guards,
  groups: [
    {
      label: 'early',
      guards: {
        solPayment: some({ lamports: sol(1), destination: treasury }),
        startDate: some({ date: dateTime('2022-10-18T16:00:00Z') }),
        endDate: some({ date: dateTime('2022-10-18T17:00:00Z') }),
        botTax: some({ lamports: sol(0.001), lastInstruction: true }),
      },
    },
    {
      label: 'late',
      guards: {
        solPayment: some({ lamports: sol(3), destination: treasury }),
        startDate: some({ date: dateTime('2022-10-18T17:00:00Z') }),
        botTax: some({ lamports: sol(0.001), lastInstruction: true }),
      },
    },
  ],
}).sendAndConfirm(umi)

API References: create, updateCandyGuard, DefaultGuardSetArgs

Default Guards

Notice how, in the example above, we had to provide the same Bot Tax guard to both groups. This can be simplified by leveraging the global Guards that are set on a Candy Machine.

When using Guard Groups, the global Guards of a Core Candy Machine — as explained on a previous page — act as default guards! That means groups will default to using the same guard settings as the global guards unless they are overriding them by explicitly enabling them in the group.

Here’s a quick recap:

If a guard is enabled on the default guards but not on the group’s guards, the group uses the guard as defined in the default guards.
If a guard is enabled on the default guards and on the group’s guards, the group uses the guard as defined in the group’s guards.
If a guard is not enabled on the default guards or the group’s guards, the group does not use this guard.

To illustrate that, let’s take our example from the previous section and move the Bot Tax guard to the default guards.

Default Guards:
- Bot Tax: 0.001 SOL
Group 1:
- Label: “early”
- Guards:
  - Sol Payment: 1 SOL
  - Start Date: 4 pm
  - End Date: 5 pm
Group 2:
- Label: “late”
- Guards:
  - Sol Payment: 2 SOL
  - Start Date: 5 pm

As you can see, default guards are useful to avoid repetition within your groups.

React Flow

Note that, even when using default guards, a group must be provided when minting. That means, when using guard groups, it is not possible to mint using the default guards only.

Create a Candy Machine with default guards and guard groups

To use default guards in the Umi library, simply use the guards attribute in conjunction with the groups array when creating or updating a Candy Machine. For instance, here’s how you’d create a Candy Machine using the guard settings described above.

import { some, sol, dateTime } from '@metaplex-foundation/umi'

await create(umi, {
  // ...
  guards: {
    botTax: some({ lamports: sol(0.001), lastInstruction: true }),
  },
  groups: [
    {
      label: 'early',
      guards: {
        solPayment: some({ lamports: sol(1), destination: treasury }),
        startDate: some({ date: dateTime('2022-10-18T16:00:00Z') }),
        endDate: some({ date: dateTime('2022-10-18T17:00:00Z') }),
      },
    },
    {
      label: 'late',
      guards: {
        solPayment: some({ lamports: sol(2), destination: treasury }),
        startDate: some({ date: dateTime('2022-10-18T17:00:00Z') }),
      },
    },
  ],
}).sendAndConfirm(umi)

API References: create, DefaultGuardSetArgs

Parallel Groups

One really interesting benefit of requiring the group label when minting is the ability to have more than one valid group at a given time. This removes any ambiguity for the program and allows the buyer to select which group they would like to try to mint from.

Let’s illustrate that with a new example. Say we have an Asset collection called “Innocent Bird” and we want to offer a discounted price of 1 SOL to anyone holding an “Innocent Bird” Asset and charge anyone else 2 SOL. We want both of these groups to be able to start minting at the same time — say 4 pm — and we also want to be protected against bots for both groups. Here’s how we could configure our guards:

Default Guards:
- Start Date: 4 pm
- Bot Tax: 0.001 SOL
Group 1:
- Label: “nft”
- Guards:
  - Sol Payment: 1 SOL
  - NFT Gate: “Innocent Bird” Collection
Group 2:
- Label: “public”
- Guards:
  - Sol Payment: 2 SOL

As you can see, with these guard settings, it is possible for both groups to mint at the same time. It is even possible for an NFT holder to pay the full 2 SOL should they decide to mint from the “public” group. However, it is in their best interest to select the “nft” group if they can.

Create a Core Candy Machine with parallel groups

Here’s how you’d create a Core Candy Machine using the guard settings described above via the Umi library.

import { some, sol, dateTime } from '@metaplex-foundation/umi'

await create(umi, {
  // ...
  guards: {
    botTax: some({ lamports: sol(0.001), lastInstruction: true }),
    startDate: some({ date: dateTime('2022-10-18T16:00:00Z') }),
  },
  groups: [
    {
      label: 'early',
      guards: {
        solPayment: some({ amount: sol(1), destination: treasury }),
        nftGate: some({
          requiredCollection: innocentBirdCollectionNft.publicKey,
        }),
      },
    },
    {
      label: 'late',
      guards: {
        solPayment: some({ amount: sol(2), destination: treasury }),
      },
    },
  ],
}).sendAndConfirm(umi)

API References: create, DefaultGuardSetArgs

Conclusion

Guard groups bring a whole new dimension to our Core Candy Machines by allowing us to define sequential and/or parallel minting workflows tailored to our needs.

On the next page, we’ll see yet another exciting feature about guards: Guard instructions!