ios-launch-performance

Name: ios-launch-performance
Author: Livsy90

88stars5forks

How to install ios-launch-performance?

livsy90/ios-performance-agent-skills/ios-launch-performance

$npx -y skills add Livsy90/iOS-Performance-Agent-Skills --skill ios-launch-performance

Installs into the current project.

Summary

Use this skill when diagnosing iOS app launch performance, startup regressions, first-frame readiness, or early responsiveness. Covers pre-main/dyld work, AppDelegate/SceneDelegate, SwiftUI App startup, launch orchestration, SDK initialization, and launch measurement. Do not use

Files · 1

View on GitHub

SKILL.md

1	# iOS Launch Performance
2
3	Use this skill to review the path from an app launch request to first visible UI and early responsiveness.
4
5	Focus on work that happens:
6
7	* before `main`
8	* during UIKit or SwiftUI startup
9	* inside `UIApplicationDelegate`, `UISceneDelegate`, or SwiftUI `App`
10	* during root UI creation
11	* before the first visible frame
12	* before the first meaningful interaction
13	* during early post-launch work that still affects user-perceived readiness
14
15	This is not a general iOS performance skill. Use it only when the issue is launch-specific or when the code runs on the launch path.
16
17	## Core Model
18
19	Treat launch as a pipeline with separate phases:
20
21	1. Process creation and system preparation
22	2. dyld loading, binding, fixups, runtime registration, and static initialization
23	3. UIKit or SwiftUI runtime startup
24	4. App-level initialization in `UIApplicationDelegate`, `UISceneDelegate`, or SwiftUI `App`
25	5. Launch orchestration and dependency setup
26	6. Root UI construction, layout, drawing, and first frame commit
27	7. Early post-launch work that affects responsiveness
28	8. Later feature-specific or maintenance work
29
30	Do not optimize blindly. First identify which phase is expensive, then recommend changes that move, remove, lazy-load, parallelize, serialize, or measure that specific work.
31
32	## When to Use This Skill
33
34	Use this skill when the task involves:
35
36	* slow app launch
37	* startup regressions
38	* cold, warm, or prewarmed launch
39	* resume-vs-launch confusion
40	* first-frame readiness
41	* early responsiveness after launch
42	* pre-main or dyld work
43	* Objective-C `+load`, `+initialize`, constructor functions, or static initialization
44	* AppDelegate or SceneDelegate startup work
45	* SwiftUI `@main App`, `WindowGroup`, root view setup, or environment injection
46	* dependency container setup during launch
47	* launch orchestrators or ordered startup steps
48	* third-party SDK initialization during launch
49	* framework linking strategy when launch cost is suspected
50	* launch metrics from Instruments, XCTest, MetricKit, or Xcode Organizer
51
52	Do not use this skill for:
53
54	* general scrolling performance
55	* memory leaks unrelated to launch
56	* rendering optimization unrelated to first frame
57	* networking performance outside startup
58	* broad architecture review unless the architecture affects the launch path
59
60	## Launch Scenario Classification
61
62	Before giving advice, classify what is being measured:
63
64	* Cold launch: the app process is not resident and little launch-related state is already warm.
65	* Warm launch: the app still starts a new process, but parts of system state, caches, or pages may already be warm.
66	* Prewarmed launch: the system may have prepared part of the launch path before the user explicitly opens the app.
67	* Resume / already-running return: the app process already exists and returns from background or suspension.
68	* First install / first run / update launch: launch includes extra setup such as migrations, cache creation, permissions, account/bootstrap work, or version-specific setup.
69	* Unknown: the measurement setup does not clearly separate the above cases.
70
71	Do not compare cold launch, warm launch, prewarmed launch, first-run launch, update launch, and resume as one metric.
72
73	Resume is not a full launch investigation unless the task explicitly asks about foregrounding latency.
74
75	## Investigation Workflow
76
77	### 1. Locate the launch path
78
79	Identify code that executes before first frame or before first meaningful interaction.
80
81	Inspect:
82
83	* app delegate
84	* scene delegate
85	* SwiftUI `App`
86	* root scene construction
87	* root view/model creation
88	* dependency container setup
89	* global/static initialization
90	* launch orchestrators
91	* SDK startup
92	* linked framework initialization
93	* first-screen routing and state restoration
94
95	### 2. Classify the slow phase
96
97	Classify the likely phase before recommending fixes:
98
99	* dyld/pre-main
100	* Objective-C or Swift runtime/static initialization
101	* app delegate startup
102	* scene delegate startup
103	* SwiftUI app/root view initialization
104	* launch orchestration or dependency setup
105	* root UI construction and first-frame rendering
106	* early post-launch responsiveness
107	* measurement ambiguity
108
109	If the available evidence is not enough to classify the phase, say so and recommend the next measurement step.
110
111	### 3. Classify startup work by necessity
112
113	For each startup task, classify it as:
114
115	* required before first frame
116	* required before first interaction
117	* needed soon after launch
118	* needed only after authentication/session state is known
119	* needed only by a later feature
120	* background maintenance
121
122	Work that is not required before first frame or fi

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ios-launch-performance

88stars5forks

View on GitHub

How to install ios-launch-performance?

livsy90/ios-performance-agent-skills/ios-launch-performance

$npx -y skills add Livsy90/iOS-Performance-Agent-Skills --skill ios-launch-performance

Installs into the current project.

Summary

Files · 1

View on GitHub

SKILL.md

1	# iOS Launch Performance
2
3	Use this skill to review the path from an app launch request to first visible UI and early responsiveness.
4
5	Focus on work that happens:
6
7	* before `main`
8	* during UIKit or SwiftUI startup
9	* inside `UIApplicationDelegate`, `UISceneDelegate`, or SwiftUI `App`
10	* during root UI creation
11	* before the first visible frame
12	* before the first meaningful interaction
13	* during early post-launch work that still affects user-perceived readiness
14
15	This is not a general iOS performance skill. Use it only when the issue is launch-specific or when the code runs on the launch path.
16
17	## Core Model
18
19	Treat launch as a pipeline with separate phases:
20
21	1. Process creation and system preparation
22	2. dyld loading, binding, fixups, runtime registration, and static initialization
23	3. UIKit or SwiftUI runtime startup
24	4. App-level initialization in `UIApplicationDelegate`, `UISceneDelegate`, or SwiftUI `App`
25	5. Launch orchestration and dependency setup
26	6. Root UI construction, layout, drawing, and first frame commit
27	7. Early post-launch work that affects responsiveness
28	8. Later feature-specific or maintenance work
29
30	Do not optimize blindly. First identify which phase is expensive, then recommend changes that move, remove, lazy-load, parallelize, serialize, or measure that specific work.
31
32	## When to Use This Skill
33
34	Use this skill when the task involves:
35
36	* slow app launch
37	* startup regressions
38	* cold, warm, or prewarmed launch
39	* resume-vs-launch confusion
40	* first-frame readiness
41	* early responsiveness after launch
42	* pre-main or dyld work
43	* Objective-C `+load`, `+initialize`, constructor functions, or static initialization
44	* AppDelegate or SceneDelegate startup work
45	* SwiftUI `@main App`, `WindowGroup`, root view setup, or environment injection
46	* dependency container setup during launch
47	* launch orchestrators or ordered startup steps
48	* third-party SDK initialization during launch
49	* framework linking strategy when launch cost is suspected
50	* launch metrics from Instruments, XCTest, MetricKit, or Xcode Organizer
51
52	Do not use this skill for:
53
54	* general scrolling performance
55	* memory leaks unrelated to launch
56	* rendering optimization unrelated to first frame
57	* networking performance outside startup
58	* broad architecture review unless the architecture affects the launch path
59
60	## Launch Scenario Classification
61
62	Before giving advice, classify what is being measured:
63
64	* Cold launch: the app process is not resident and little launch-related state is already warm.
65	* Warm launch: the app still starts a new process, but parts of system state, caches, or pages may already be warm.
66	* Prewarmed launch: the system may have prepared part of the launch path before the user explicitly opens the app.
67	* Resume / already-running return: the app process already exists and returns from background or suspension.
68	* First install / first run / update launch: launch includes extra setup such as migrations, cache creation, permissions, account/bootstrap work, or version-specific setup.
69	* Unknown: the measurement setup does not clearly separate the above cases.
70
71	Do not compare cold launch, warm launch, prewarmed launch, first-run launch, update launch, and resume as one metric.
72
73	Resume is not a full launch investigation unless the task explicitly asks about foregrounding latency.
74
75	## Investigation Workflow
76
77	### 1. Locate the launch path
78
79	Identify code that executes before first frame or before first meaningful interaction.
80
81	Inspect:
82
83	* app delegate
84	* scene delegate
85	* SwiftUI `App`
86	* root scene construction
87	* root view/model creation
88	* dependency container setup
89	* global/static initialization
90	* launch orchestrators
91	* SDK startup
92	* linked framework initialization
93	* first-screen routing and state restoration
94
95	### 2. Classify the slow phase
96
97	Classify the likely phase before recommending fixes:
98
99	* dyld/pre-main
100	* Objective-C or Swift runtime/static initialization
101	* app delegate startup
102	* scene delegate startup
103	* SwiftUI app/root view initialization
104	* launch orchestration or dependency setup
105	* root UI construction and first-frame rendering
106	* early post-launch responsiveness
107	* measurement ambiguity
108
109	If the available evidence is not enough to classify the phase, say so and recommend the next measurement step.
110
111	### 3. Classify startup work by necessity
112
113	For each startup task, classify it as:
114
115	* required before first frame
116	* required before first interaction
117	* needed soon after launch
118	* needed only after authentication/session state is known
119	* needed only by a later feature
120	* background maintenance
121
122	Work that is not required before first frame or fi

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6 picks

Type