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    • Automatic Update & Build

    Overview

    The instructions provided for building with a browser include settings to automatically update and build for you.

    Automatic Build

    Automatic Build Returns for Loop v3.14.7 and newer

    With v3.14.7, a new file name is used for automatic building using the Browser Build method.

    • The new file: build_loop_auto.yml has the same content as the older build_loop.yml
      • It appears that just giving it a new name was enough to prevent GitHub from disabling the build process
      • Once you update to v3.14.7 or newer, your automatic building will be restored
    • The old file: build_loop.yml is still in your LoopWorkspace folder for your convenience
      • It no longer has the instructions to run automatically (that did not work anyway)
      • If you had customization lines in build_loop.yml, they should still be there
      • Simply copy those lines from build_loop.yml to build_loop_auto.yml to transfer the customization instructions to the file that actually runs to build Loop once a month

    The Actions shown for Loop were modified with the v3.14.7 release. The new build_loop_auto.yml file shows up as Build Loop Auto and actually runs every Sunday. The existing build_loop.yml shows up as Build Loop Manual. It can still be run manually, but it no longer is triggered automatically and continues to show as Disabled.

    the new build loop auto is automatic

    Skipped Build

    The automatic build process checks once a week for updates to the main branch. If there are no updates, it skips the build unless it is the second Sunday of the month.

    clear indication if build was skipped or successful

    Manual Action for Automatic Build

    Browser Build for Loop Disabled?

    GitHub disables the Build Loop Action for LoopWorkspace for v3.14.2 and older. Please update your fork to bring in the changes for v3.14.7 (or newer). See: Automatic Build

    Stale Repositoriy Always Requires Manual Action (Click to Open Close)

    GitHub automatically disables actions that run according to a schedule if the repository in question is inactive.

    What does that mean?

    • inactive means stable code (no new commit within the last 60 days)
    • disables actions means the Build Action shows up as disabled

    What Manual Action is Required?

    For any repository that shows the build action disabled, you should enable the action and do a manual build.

    fix a disabled build state

    This keeps the most recent version of your app available in TestFlight for you to install when you are ready. This manual enable step should be required no more frequently than every 60 days, however, best to make it a monthly habit to check.

    Builds in TestFlight are good for 90 days before they expire.

    Your build may fail for other reasons - most common is forgetting to sign your updated license agreement or not adding the variable needed to get automatic annual certification renewal.

    What is Automatic

    These events are automatically scheduled:

    You Get No Warning if Repository Build Action is Disabled

    These automatic actions happen on schedule, but if your build action is disabled, no build actually happens, no warning email is sent and a green checkmark (✅) appears beside a very short build action in which the actual build was skipped.

    If you do not want this automatic schedule, you can modify it.

    Regardless of your choice, please Disable Automatic Installation from TestFlight. You should be alert any time your Loop app is updated. Check that all settings are maintained and pay attention to make sure the app behavior is nominal.

    You still need to take these actions to ensure a recent build of the Loop app is available in TestFlight for you to install on your phone when you choose:

    Modified Design for Build Action

    The modified design for the build action found in Loop v3.8.2 and newer is documented in this section.

    Updated Build Features

    The code that controls the build process was streamlined and enhanced. It runs every Sunday at a time when GitHub is not impacted. The portion of the action that decides whether to build or not completes in a few seconds.

    Build when

    Other features

    Do you want to know more? (Click to open/close)

    Build Action Redesign

    When GitHub allowed the use of alive branches with automatic addition of commits to the branch, there were extra steps in the build yml file and limitations to which branches would be updated.

    • These steps kept your fork from getting stale
    • GitHub will disable your build actions if no commits have been added for 60 days

    Because this trick is no longer allowed, the creation and use of alive branches was removed. That opened the door to streamline and enhance the build action capabilities.

    If you want to follow the detailed design steps taken to reach this new version, see the following LoopFollow PR. (Most people do not need to know this).

    Successful Weekly Action

    Normally, you will see a successful build action once a week. This happens every Sunday (as soon as your version is 3.8.2 or newer).

    Previously the build action would run every Wed or the first of the month, when GitHub resources were impacted.

    If there are no updates to the main branch, your actions show a very short, successful build action as shown in the graphic below. It only takes a few seconds because the logic says - if no update was detected and it is not the second Sunday, then skip checking the certificates and skip the build.

    normal weekly check for updates when there are no updates

    If there is an update, the build action updates your fork and creates a new build.

    In that case, you should check your favorite information site to find out what the update was and then, when you are ready, install the update using the TestFlight app on your phone.

    Successful Monthly Action

    On the second Sunday of every month, you will see a longer build action. The purpose of this build is to provide a recent version of the app in TestFlight so you are never in a situation where you have no app on your phone.

    Previously the build action would run every Wed or the first of the month, when GitHub resources were impacted.

    You Get No Warning if Repository Build Action is Disabled

    If your build action is disabled, no build actually happens, no warning email is sent and a green checkmark (✅) appears beside a very short build action in which the actual build was skipped.

    You start getting Notifications when there are fewer than 20 days until expiration. When you see the warning, install the newest build from your TestFlight app. You do not want to get the dreaded "Loop Beta is not available" message on your phone. (The warnings get very agressive when close to expiration.)

    What are the alive branches?

    In April 2025, GitHub disallowed using the build action to automatically add commits to alive branches. This trick was previously used to keep your fork active even when the upstream repository was stable.

    Once you update to v3.8.2 or newer, references to alive branches are removed from the build action.

    • If you have alive branches (alive, alive-dev or alive-main) you may delete them if you choose
    • Only delete alive branches after your default branch is updated to the new version

    Automatic Certificates

    Automatic renewal of certificates is included in Loop 3.6.0 and newer versions.

    Requirements

    You must have the ENABLE_NUKE_CERTS variable set to true for your GitHub organization, or when using a personal account to build, add it to each repository.

    Do you want to know more? (Click to open/close)

    Annual Renewal

    Once a year, Apple automatically expires your Distribution Certificate.

    • When the Apple Distribution certificate expires, the saved credentials in your Match-Secrets private repository are invalid and need to be removed (nuke)
    • You need a new Distribution Certificate at Apple
    • You need to create new signing credentials for Match-Secrets

    For the Loop app, up through version 3.4.4, you had to do this Renew Certificate process manually. Now that version 3.6.0 is released, it is automatic.

    Automatic Certificate Renewal

    Some Open-Source apps, in particular Trio, LoopCaregiver, LoopFollow, Loop and iAPS have automatic certificate renewal.

    Open-Source App Schedule

    With the release of Loop 3.8.2 and newer, the build schedule is updated.

    New schedule - there will be one automatic run of the build action each week on Sunday.

    The table below indicates planned time for the automatic build schedule. GitHub will start the build action no earlier than the stated time but it can be delayed depending on activity at GitHub.

    For apps not yet changed to the new method, the weekly runs are on Wednesday and the monthly runs are on the 1st of each month.

    Open-Source App AutoCerts? Weekly
    UTC    		 Once a Month
    UTC
    Loop ✅ 07:33 same
    LoopCaregiver ✅ 13:33 11:33
    LoopFollow ✅ 10:17 same
    LoopFollow_Second ✅ 10:27 same
    LoopFollow_Third ✅ 10:40 same
    Trio ✅ 06:43 same
    xDrip4iOS ❌ 16:43 14:43
    iAPS ✅ 03:00 daily n/a

    The iAPS app uses a different system to trigger updates

    • daily check for updates
    • autobuild when updates detected (if user opts in)

    Why are the Hour and Minute staggered?

    There are 2 reasons:

    1. You only want one action to nuke profiles and build credentials associated with an expired certificate
    2. The GitHub resources are more likely to be busy at the beginning of each hour
    Do you want to know more? (Click to Open/Close)

    This build schedule determines when the automatic check for certificate status happens. The times are shifted to make sure only one Open-Source app performs a nuke action. Any other app building later that same day will just create new signing credentials; it will not need to nuke. This only happens once a year, but we wanted to be sure there are no conflicts.

    Starting in 2025 May, some people were getting messages that "no runners" were available to perform their build. (Remember, this is a free service we are using.) Initially, all builds started at the "top of the hour" (HH:00), but it turns out that is when GitHub has the most activity. In an attempt to minimize build failures due to resource limitations, the minute of the hour for all the apps is gradually being shifted.

    When the first of the month and Wednesday came on the same day, there were many failed builds. This triggered us to redesign the timing. The new design is for only one run of a build action per week, on Sunday, and inside that build action there is logic to decide if it is the second Sunday of the month. If so, the build is always run and not skipped.

    Even if an app doesn't have automatic certificates implemented yet, they are added to the table as suggested values to use when this capability gets added. All times are UTC. If other apps decide to add this feature, please make a pull request to LoopDocs so we can add those times to the deconfliction table.

    Modify Automatic Building

    For someone using development code for their own use, they could decide to choose when to update their fork to the most recent commit. They can still have the advantage of automatic building without automatic updates; in other words, they want a new build added to TestFlight every month. There may be other configurations someone would choose. These options are available starting with Loop 3.3.0 (dev branch) and later.

    You can affect the default behavior:

    1. Modify Automatic Schedule
    2. Disable Automatic Actions

    Modify Automatic Schedule

    This is an optional step. If you are happy with the automatic sync and update, you are done with this page.

    Instructions to Modify the Automatic Actions (Click to Open/Close)

    You can modify the automation by creating and using some variables.

    To configure the automated build more granularly involves creating up to two variables: SCHEDULED_BUILD and/or SCHEDULED_SYNC. See How to configure a variable.

    Note that the weekly and monthly Build Loop actions will continue, but the actions are modified if one or more of these variables is set to false. A successful Action Log will still appear, even if no automatic activity happens.

    • If you want to manually decide when to update your repository to the latest commit, but you want the monthly builds to continue:
      • create the variable SCHEDULED_SYNC and set it to false
      • either do not create the variable SCHEDULED_BUILD or set it to true
      • If you are building the dev branch at a time when there is a lot of activity in that branch, you may want this configuration
    • If you want to only build when an update has been found:
      • either do not create the variable SCHEDULED_SYNC or set it to true
      • create the variable SCHEDULED_BUILD and set it to false
      • Warning: if no updates to your default branch are detected within 90 days, your previous TestFlight build may expire, requiring a manual build
      • During a time when updates are not happening frequently, this is not a good choice
    SCHEDULED_SYNC
    SCHEDULED_BUILD
    		 Automatic Actions
    true (or N/A) true (or N/A) This is the default:
    weekly update check (auto update/build), monthly build with auto update
    false true (or N/A) monthly build, no auto update
    true (or N/A) false weekly update check with auto update, only builds if update detected
    false false no automatic activity

    How to configure a variable

    1. Go to the "Settings" tab of your LoopWorkspace repository.
    2. Click on Secrets and Variables.
    3. Click on Actions
    4. You will now see a page titled Actions secrets and variables. Click on the Variables tab
    5. To disable ONLY scheduled building, do the following:
      • Click on the green New repository variable button (upper right)
      • Type SCHEDULED_BUILD in the "Name" field
      • Type false in the "Value" field
      • Click the green Add variable button to save.
    6. To disable scheduled syncing, add a variable:
      • Click on the green New repository variable button (upper right)
        • Type SCHEDULED_SYNC in the "Name" field
      • Type false in the "Value" field
      • Click the green Add variable button to save

    Your build will run on the following conditions:

    Disable Automatic Actions

    To enable the scheduled build and sync, the GH_PAT must hold the workflow permission scopes. This permission serves as the enabler for automatic and scheduled builds with browser build. To disable this, follow these steps:

    1. Go to your FastLane Access Token
    2. If it says repo, workflow next to the FastLane Access Token link, then automatic building is enabled
    3. To disable automatic update and build, click on the link to open the token detail view
      • Click to uncheck the workflow box
      • Click to check the repo box
    4. Scroll all the way down to and click the green Update token button
    5. Your token now holds only the repo permission

    If you choose not to have automatic building enabled, be sure the GH_PAT has repo scope or you won't be able to manually build.

    Stop Building

    What if I decide I don't want the automatic building feature?