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Glossary

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Actions  (Actions): a custom application for the GitHub Actions platform that performs a complex but frequently repeated task; specifically used to build Loop from a browser

Activated  (Activated): for Omnipod: time at which insulin was injected into pod and 2 beeps were heard

Anchor Links  (Anchor Links): any header on a LoopDocs page can be used as a link, tap on the paragraph symbol at the end of the header to view the link in the URL

API_SECRET  (API_SECRET): password (min 12 characters) needed to access Nightscout Site

API  (API): Application Programming Interface

APN  (APN): Apple Push Notification service, required for issuing remote command via Nightscout

App Group  (App Group): a unique identifier that Apple users for a given app, yours has your TEAMID embedded in it, group.com.TEAMID.loopkit.LoopGroup

Automatic Bolus  (Automatic Bolus): provide a fraction of the recommended insulin automatically with each updated CGM reading (default 40%)

BAGE  (BAGE): pump battery age on Nightscout site

Big Sur  (Big Sur): older version for operating system for Mac, macOS 11.x

BLE  (BLE): Bluetooth low energy, used for communication by phones, CGM and some pumps

Build Select Script  (Build Select Script): by running a command in your terminal, this menu-driven tool assists in building Loop

branch  (branch): version of code within a single repository or workspace repository

CAGE  (CAGE): cannula (or pump site) age on Nightscout site

carthage  (carthage): a program that used to be required to build Loop - no longer needed

Catalina  (Catalina): older version for operating system for Mac, macOS 10.x

Certificate  (Certificate): Apple certificate is used to sign your iOS or Mac apps - tied to but different from your permanent Developer ID

CGM  (CGM): continuous glucose monitor, wearable medical device that measures and reports glucose in interstitial fluid

Closed Loop  (Closed Loop): Loop will make automated adjustments of insulin delivery using predictions based off user entries, settings, IOB and COB

Open Loop  (Open Loop): Loop will not make automated adjustments of insulin delivery but predictions and recommendation features are available

clone  (clone): create a copy of a repository on your computer including revision history and ability to update using git commands

COB  (COB): Carbs on Board, affects automated insulin delivery: the g of carbohydrates that Loop expects to be absorbed and uses for glucose prediction

commit  (commit): a formal change to files in a repository; each commit has an alphanumeric identifier (SHA-1)

Config Vars  (Config Vars): configuration parameters for a Nightscout Site

Correction Factor  (Correction Factor): how many points your blood sugar will drop for each unit of insulin; Loop calls this Insulin Sensitivity Factor (ISF)

Correction Range  (Correction Range): Loop recommends changes to basal and / or bolus to bring glucose predictions into this range

CR  (CR): Carb Ratio; how many grams of carbs are covered by one unit of rapid-acting insulin

Delivery Limits  (Delivery Limits): max bolus and max basal rates allowed by your therapy settings

Developer Mode  (Developer Mode): Extra security for iOS 16 and newer; this must be turned on to allow an app built from Xcode directly to the phone to run on a phone or watch

DIA  (DIA): Duration of Insulin Action, the full time insulin is active including a long, low-level tail

DIY  (DIY): Do it yourself, a common acronym for the open-source software community (and the maker community)

Dosing Strategy  (Dosing Strategy): chosen method for increased insulin dosing: (1) High Temp Basal or (2) Automatic Bolus with scheduled basal

dynos  (dynos): used to reboot a Nightscout Site

dynamic carb absorption  (dynamic carb absorption): Loop models the expected glucose change based on carbs entered, absorption time and your settings; and adjusts based on measured glucose

EmaLink  (EmaLink): radio-frequency device Loop uses to control Eros pods (aka. Gen 3) and older Medtronic pumps

ENABLE_NUKE_CERTS  (ENABLE_NUKE_CERTS): The Variable that gets added to GitHub, along with your 6 Secrets: renews your Apple Developer Certificate after it expires

EGP  (EGP): Endogenous Glucose Production: glucose produced by the body from its reserves (mainly glycogen in the liver)

Event History  (Event History): record of pump events (bolus or temp basal) reported and used by Loop

Expiration Date  (Expiration Date): your Loop app has a finite life, the app warns you starting 3 weeks before the expiration date

fastlane  (fastlane): used as part of the GitHub Build Action method that enables building Loop without a Mac computer or Xcode

Finder  (Finder): graphical folder and file display on Mac

fork  (fork): a copy of code in a GitHub repository other than the original

GBPA  (GBPA): Glucose Based Partial Application: modification to Automatic Bolus Dosing Strategy

GIF  (GIF): Graphics Interchange Format (GIF) can be used for small animations and low-resolution video clips

git  (git): a tool for version control

GitHub  (GitHub): an online service for storing repositories, accessible from a browser

github.com  (github.com): an online service for storing repositories, accessible from a browser

GitHub Personal Access Token  (GitHub Personal Access Token): used to enable Browser Build of Loop

Glucose Chart  (Glucose Chart): Display of measured and predicted glucose values

Glucose Safety Limit  (Glucose Safety Limit): Loop will not suggest insulin delivery when glucose prediction (in next 3 hours) goes below this limit; in Loop 2 this was called Suspend Threshold

GMT  (GMT): Greenwich Mean Time is mean (average) solar time at 0 degrees longitude, see UTC

Guardrails  (Guardrails): limits in the code for user selected settings, recommended and absolute limits are provided

Hamburger Menu  (Hamburger Menu): three parallel lines that, when tapped, open a new menu

HUD  (HUD): Heads-Up Display at top of Loop main screen, phone in portrait mode

ICE  (ICE): Insulin Counteraction Effect - Refers to the difference between observed change in blood glucose and the change in blood glucose that Loop models based on the effects of insulin.

Identifiers  (Identifiers): names of modules found on your Apple Developer Identifiers page that are required for GitHub build method

IOB  (IOB): Insulin on Board, affects automated insulin delivery: the current active insulin (above or below the basal rate) that Loop calculates and uses for glucose prediction

iOS  (iOS): operating system used by Apple Mobile devices (iPhone, iPod, iPad)

IRC  (IRC): Integral Retrospective Correction: Optional alternative to Retrospective Correction that integrates glucose deviations over a longer time frame

ISF  (ISF): Insulin Sensitivity Factor; how many points your blood sugar will drop for each unit of insulin; sometimes called Correction Factor

Issue  (Issue): On GitHub - a formal method to report a problem, either code behavior or documentation

JSON  (JSON): JavaScript Object Notation; a standard data interchange format that is text-based and human readable

macOS  (macOS): operating system for Mac computer

Lock your Phone  (Lock your Phone): click the button on the side of the phone to lock it - prevent accidental touch, i.e., accidental Loop command

Loop  (Loop): With a capital L, Loop is one of several do-it-yourself artifical pancreas systems

Loop 3  (Loop 3): Latest release with major updates

Loop Cycle  (Loop Cycle): typically 5 minutes: new CGM reading, prediction update, pump update and, if in Closed Loop, dosing update if needed

LoopCaregiver  (LoopCaregiver): An app you can build to provide remote commands to Loop using Nightscout

LoopFollow  (LoopFollow): An app you can build to provide extra alarms and views of important information - can use Dexcom Share or Nightscout to include Loop information

Match-Secrets  (Match-Secrets): a private repository that is automatically created for you in your GitHub account, stores keys required to build with GitHub Build Actions. There is no need for you to interact with this repository

MTB  (MTB): Manual Temp Basal: user initiated temporary basal, Omnipod Common feature

MDT  (MDT): common abbreviation for Medtronic pumps

modal  (modal): message or alert appearing in front of app that must be acknowledged to return to app

Modules  (Modules): the Loop code uses a number of modules to handle different components of the entire app

Monterey  (Monterey): operating system for Mac, macOS 12.x

MPC  (MPC): model predictive control; the type of control algorithm used by Loop

NFC  (NFC): Near-Field Communication is used for scanning devices such as Libre sensors

Nightscout  (Nightscout): a personal website used to view your glucose and diabetes management data, Loop can upload to Nightscout

nuke  (nuke): clear signing credentials from your Match-Secrets repository

Onboarding  (Onboarding): familiarize new, and existing, Loop users with settings in Loop 3 and ensure the Therapy Settings are all entered and are within safety guardrails

Omnipod  (Omnipod): Insulet tubeless insulin pump; Loop supports Eros (with RileyLink) and DASH. Eros is also known as Classic, UST400, and System.

OrangeLink  (OrangeLink): radio-frequency device Loop uses to control Eros pods (aka. Gen 3) and older Medtronic pumps

OTP  (OTP): one-time password, this is used to enable caregivers to securely execute remote commands to a Looper's phone

Override  (Override): a modification to Loop settings that can change the correction range, the sensitivity (basal, ISF and CR) or both. Accessed by clicking the heart symbol on Loop's mainscreen, and referred to as a Custom Preset within the Loop app.

Package Dependencies  (Package Dependencies): packages that must be downloaded by Xcode (once) to build the app after downloading the LoopWorkspace to your computer

pill  (pill): on Nightscout, small boxes with information, tap for extra details

PR  (PR): Pull Request - a formal method to request changes to a repository

prebolus  (prebolus): take some or all of a meal bolus before eating

Pre-Meal Range  (Pre-Meal Range): modify the correction range for up to one hour by tapping on an icon in the toolbar

Provisioning Profile  (Provisioning Profile): associates your app with your Developer ID and limits app lifetime to 1 year (paid) or 1 week (free)

Pull Request  (Pull Request): formal method to request changes to a repository

QR  (QR): a machine-readable code consisting of an array of black and white squares

Quit the Loop App  (Quit the Loop App): quit out of the app - different from closing the app - typically you swipe up in the app switcher

repository  (repository): contains project files and each file's revision history

RileyLink  (RileyLink): radio-frequency device Loop uses to control Eros pods (aka. Gen 3) and older Medtronic pumps

RC  (RC): Retrospective Correction: part of the Loop model that considers actual glucose compared to earlier predictions

SAGE  (SAGE): sensor age on Nightscout site

Secrets  (Secrets): a method to securely embed personal information into your fork of LoopWorkspace to enable GitHub to have access required to build Loop

TEAMID  (TEAMID): One of 6 Secrets: Apple Developer account member number

FASTLANE_ISSUER_ID  (FASTLANE_ISSUER_ID): One of 6 Secrets: the issuer ID is associated with your Apple Developer ID and never changes

FASTLANE_KEY_ID  (FASTLANE_KEY_ID): One of 6 Secrets: Key ID provided when you create an API key in App Store Connect; it is associated with the FASTLANE_KEY

FASTLANE_KEY  (FASTLANE_KEY): One of 6 Secrets: Really long key (several lines); it and FASTLANE_KEY_ID are generated together

GH_PAT  (GH_PAT): One of 6 Secrets: Generated with your GitHub account; set it to never expire

MATCH_PASSWORD  (MATCH_PASSWORD): One of 6 Secrets: GitHub repository encryption passphrase, used to encrypt the Match-Secrets repository when it is created. You must save and use the same MATCH_PASSWORD for every repository if you build multiple apps.

SHA-1  (SHA-1): Secure Hash Algorithm 1; used to generate an alphanumeric code for commits in git (GitHub)

Sign Targets  (Sign Targets): associate a Developer ID with an app; must sign all targets for a given app

submodules  (submodules): for Loop, submodules are repositories defined in the Workspace repository that are required to build the app

Table of Contents  (Table of Contents): (TOC) is the list of level 2 and 3 headers on a given page; the title at the top of the page is a level 1 header

Tahoe  (Tahoe): operating system for Mac, macOS 26.x

Temp Basal Only  (Temp Basal Only): provide the recommended insulin automatically using an increase in temp basal over half an hour (limited by max temp basal)

Temp Basal  (Temp Basal): modify the scheduled basal rate for a pump

Terminal  (Terminal): interface for entering commands to the computer

TestFlight  (TestFlight): a method to distribute apps without direct connection

Therapy Settings  (Therapy Settings): Basal Rates, ISF, CR, correction and safety ranges and delivery limits

Tokens  (Tokens): in Nightscout Admin Tools, configure access permissions using tokens

Tooltip  (Tooltip): brief definitions provided for important terms and abbreviations on the website

URL  (URL): website address (Uniform Resource Locator)

UTC  (UTC): Coordinated Universal Time is a time standard for civil time and time zones worldwide

watchOS  (watchOS): Apple watch operating system; must be compatible with phone iOS

workflow  (workflow): a set of instructions to GitHub to perform an action; the instruction files are found in the .github/workflows folder of the repository

Workspace  (Workspace): a grouping of several repositories into a complete package

Xcode Preferences  (Xcode Preferences): older name for Xcode Settings

Xcode Settings  (Xcode Settings): as of Xcode 14, Xcode menu uses Settings instead of Preferences

Xcode  (Xcode): program used to build an app