Implement dependency lock for stability, consistency, and reproducibility #954

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Implement dependency lock for stability, consistency, and reproducibility#954
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i-am-sijia
opened on Jun 12, 2025

ActivitySim relies on numerous third-party Python packages, i.e., its dependencies. ActivitySim users occasionally report installation and/or runtime failures due to these dependencies (#919, #921). This typically happens when one or more of the dependencies is updated to a new version. Unless explicitly specified, ActivitySim looks for and installs the latest versions of its dependencies. The latest versions of dependencies can conflict with each other and/or have API updates that are no longer backward compatible with ActivitySim.

ActivitySim’s current solution is to specify version ranges for select dependencies, see here for an example. When conflicts arise, additional dependencies are added to this list. This approach has been effective, but is passive and sub-optimal: new conflicts are bound to arise. Recently, users have not been able to install and run ActivitySim because one of its second order dependencies (i.e., a dependency of a dependency), “multimethod”, has a new version that is not compatible with ActivitySim (#919). Therefore, the ActivitySim Consortium desires a more proactive solution.

This is a common problem in Python and a common solution is to “lock” Python dependencies to create “deterministic” builds (i.e., specify versions of each dependency, including dependencies of dependencies, used by ActivitySim). Locking Python dependencies improves consistency, reproducibility, and stability across environments for development, testing, and production.

There are many tools available for locking Python dependencies. With tools like uv, pdm, or poetry, the exact versions of all dependencies ActivitySim requires are specified, reducing the chances of unexpected issues caused by updates or version mismatches.

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all 
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '

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Implement dependency lock for stability, consistency, and reproducibility #954
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Implement dependency lock for stability, consistency, and reproducibility#954
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i-am-sijia
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@i-am-sijia
i-am-sijia
opened on Jun 12, 2025
ActivitySim relies on numerous third-party Python packages, i.e., its dependencies. ActivitySim users occasionally report installation and/or runtime failures due to these dependencies (#919, #921). This typically happens when one or more of the dependencies is updated to a new version. Unless explicitly specified, ActivitySim looks for and installs the latest versions of its dependencies. The latest versions of dependencies can conflict with each other and/or have API updates that are no longer backward compatible with ActivitySim.
ActivitySim’s current solution is to specify version ranges for select dependencies, see here for an example. When conflicts arise, additional dependencies are added to this list. This approach has been effective, but is passive and sub-optimal: new conflicts are bound to arise. Recently, users have not been able to install and run ActivitySim because one of its second order dependencies (i.e., a dependency of a dependency), “multimethod”, has a new version that is not compatible with ActivitySim (#919). Therefore, the ActivitySim Consortium desires a more proactive solution.
This is a common problem in Python and a common solution is to “lock” Python dependencies to create “deterministic” builds (i.e., specify versions of each dependency, including dependencies of dependencies, used by ActivitySim). Locking Python dependencies improves consistency, reproducibility, and stability across environments for development, testing, and production.
There are many tools available for locking Python dependencies. With tools like uv, pdm, or poetry, the exact versions of all dependencies ActivitySim requires are specified, reducing the chances of unexpected issues caused by updates or version mismatches.
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix");
}
} catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Implement dependency lock for stability, consistency, and reproducibility #954
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Implement dependency lock for stability, consistency, and reproducibility#954
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i-am-sijia
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@i-am-sijia
i-am-sijia
opened on Jun 12, 2025
ActivitySim relies on numerous third-party Python packages, i.e., its dependencies. ActivitySim users occasionally report installation and/or runtime failures due to these dependencies (#919, #921). This typically happens when one or more of the dependencies is updated to a new version. Unless explicitly specified, ActivitySim looks for and installs the latest versions of its dependencies. The latest versions of dependencies can conflict with each other and/or have API updates that are no longer backward compatible with ActivitySim.
ActivitySim’s current solution is to specify version ranges for select dependencies, see here for an example. When conflicts arise, additional dependencies are added to this list. This approach has been effective, but is passive and sub-optimal: new conflicts are bound to arise. Recently, users have not been able to install and run ActivitySim because one of its second order dependencies (i.e., a dependency of a dependency), “multimethod”, has a new version that is not compatible with ActivitySim (#919). Therefore, the ActivitySim Consortium desires a more proactive solution.
This is a common problem in Python and a common solution is to “lock” Python dependencies to create “deterministic” builds (i.e., specify versions of each dependency, including dependencies of dependencies, used by ActivitySim). Locking Python dependencies improves consistency, reproducibility, and stability across environments for development, testing, and production.
There are many tools available for locking Python dependencies. With tools like uv, pdm, or poetry, the exact versions of all dependencies ActivitySim requires are specified, reducing the chances of unexpected issues caused by updates or version mismatches.
Metadata
Metadata
Assignees
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FeatureNew feature or request
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None yet
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No branches or pull requests
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms");
}
} catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Implement dependency lock for stability, consistency, and reproducibility #954
Closed
Feature
Closed
Implement dependency lock for stability, consistency, and reproducibility#954
Feature
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i-am-sijia
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FeatureNew feature or request
Description
@i-am-sijia
i-am-sijia
opened on Jun 12, 2025
ActivitySim relies on numerous third-party Python packages, i.e., its dependencies. ActivitySim users occasionally report installation and/or runtime failures due to these dependencies (#919, #921). This typically happens when one or more of the dependencies is updated to a new version. Unless explicitly specified, ActivitySim looks for and installs the latest versions of its dependencies. The latest versions of dependencies can conflict with each other and/or have API updates that are no longer backward compatible with ActivitySim.
ActivitySim’s current solution is to specify version ranges for select dependencies, see here for an example. When conflicts arise, additional dependencies are added to this list. This approach has been effective, but is passive and sub-optimal: new conflicts are bound to arise. Recently, users have not been able to install and run ActivitySim because one of its second order dependencies (i.e., a dependency of a dependency), “multimethod”, has a new version that is not compatible with ActivitySim (#919). Therefore, the ActivitySim Consortium desires a more proactive solution.
This is a common problem in Python and a common solution is to “lock” Python dependencies to create “deterministic” builds (i.e., specify versions of each dependency, including dependencies of dependencies, used by ActivitySim). Locking Python dependencies improves consistency, reproducibility, and stability across environments for development, testing, and production.
There are many tools available for locking Python dependencies. With tools like uv, pdm, or poetry, the exact versions of all dependencies ActivitySim requires are specified, reducing the chances of unexpected issues caused by updates or version mismatches.
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links");
}
} catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); }
})();
(function(){
try {
var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '

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Implement dependency lock for stability, consistency, and reproducibility #954
Closed
Feature
Closed
Implement dependency lock for stability, consistency, and reproducibility#954
Feature
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i-am-sijia
Labels
FeatureNew feature or request
Description
@i-am-sijia
i-am-sijia
opened on Jun 12, 2025
ActivitySim relies on numerous third-party Python packages, i.e., its dependencies. ActivitySim users occasionally report installation and/or runtime failures due to these dependencies (#919, #921). This typically happens when one or more of the dependencies is updated to a new version. Unless explicitly specified, ActivitySim looks for and installs the latest versions of its dependencies. The latest versions of dependencies can conflict with each other and/or have API updates that are no longer backward compatible with ActivitySim.
ActivitySim’s current solution is to specify version ranges for select dependencies, see here for an example. When conflicts arise, additional dependencies are added to this list. This approach has been effective, but is passive and sub-optimal: new conflicts are bound to arise. Recently, users have not been able to install and run ActivitySim because one of its second order dependencies (i.e., a dependency of a dependency), “multimethod”, has a new version that is not compatible with ActivitySim (#919). Therefore, the ActivitySim Consortium desires a more proactive solution.
This is a common problem in Python and a common solution is to “lock” Python dependencies to create “deterministic” builds (i.e., specify versions of each dependency, including dependencies of dependencies, used by ActivitySim). Locking Python dependencies improves consistency, reproducibility, and stability across environments for development, testing, and production.
There are many tools available for locking Python dependencies. With tools like uv, pdm, or poetry, the exact versions of all dependencies ActivitySim requires are specified, reducing the chances of unexpected issues caused by updates or version mismatches.
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Metadata
Assignees
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FeatureNew feature or request
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None yet
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default");
}
} catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

Skip to content
Implement dependency lock for stability, consistency, and reproducibility #954
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Closed
Implement dependency lock for stability, consistency, and reproducibility#954
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i-am-sijia
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@i-am-sijia
i-am-sijia
opened on Jun 12, 2025
ActivitySim relies on numerous third-party Python packages, i.e., its dependencies. ActivitySim users occasionally report installation and/or runtime failures due to these dependencies (#919, #921). This typically happens when one or more of the dependencies is updated to a new version. Unless explicitly specified, ActivitySim looks for and installs the latest versions of its dependencies. The latest versions of dependencies can conflict with each other and/or have API updates that are no longer backward compatible with ActivitySim.
ActivitySim’s current solution is to specify version ranges for select dependencies, see here for an example. When conflicts arise, additional dependencies are added to this list. This approach has been effective, but is passive and sub-optimal: new conflicts are bound to arise. Recently, users have not been able to install and run ActivitySim because one of its second order dependencies (i.e., a dependency of a dependency), “multimethod”, has a new version that is not compatible with ActivitySim (#919). Therefore, the ActivitySim Consortium desires a more proactive solution.
This is a common problem in Python and a common solution is to “lock” Python dependencies to create “deterministic” builds (i.e., specify versions of each dependency, including dependencies of dependencies, used by ActivitySim). Locking Python dependencies improves consistency, reproducibility, and stability across environments for development, testing, and production.
There are many tools available for locking Python dependencies. With tools like uv, pdm, or poetry, the exact versions of all dependencies ActivitySim requires are specified, reducing the chances of unexpected issues caused by updates or version mismatches.
Metadata
Metadata
Assignees
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FeatureNew feature or request
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No milestone
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None yet
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No branches or pull requests
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers");
}
} catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); }
})();
(function(){
try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '

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Implement dependency lock for stability, consistency, and reproducibility #954
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Closed
Implement dependency lock for stability, consistency, and reproducibility#954
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i-am-sijia
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@i-am-sijia
i-am-sijia
opened on Jun 12, 2025
ActivitySim relies on numerous third-party Python packages, i.e., its dependencies. ActivitySim users occasionally report installation and/or runtime failures due to these dependencies (#919, #921). This typically happens when one or more of the dependencies is updated to a new version. Unless explicitly specified, ActivitySim looks for and installs the latest versions of its dependencies. The latest versions of dependencies can conflict with each other and/or have API updates that are no longer backward compatible with ActivitySim.
ActivitySim’s current solution is to specify version ranges for select dependencies, see here for an example. When conflicts arise, additional dependencies are added to this list. This approach has been effective, but is passive and sub-optimal: new conflicts are bound to arise. Recently, users have not been able to install and run ActivitySim because one of its second order dependencies (i.e., a dependency of a dependency), “multimethod”, has a new version that is not compatible with ActivitySim (#919). Therefore, the ActivitySim Consortium desires a more proactive solution.
This is a common problem in Python and a common solution is to “lock” Python dependencies to create “deterministic” builds (i.e., specify versions of each dependency, including dependencies of dependencies, used by ActivitySim). Locking Python dependencies improves consistency, reproducibility, and stability across environments for development, testing, and production.
There are many tools available for locking Python dependencies. With tools like uv, pdm, or poetry, the exact versions of all dependencies ActivitySim requires are specified, reducing the chances of unexpected issues caused by updates or version mismatches.
Metadata
Metadata
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, 'i');
if (__m === '*' || __re.test(location.href)) {
injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode");
}
} catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); }
})();
})();

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Implement dependency lock for stability, consistency, and reproducibility #954
Closed
Feature
Closed
Implement dependency lock for stability, consistency, and reproducibility#954
Feature
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i-am-sijia
Labels
FeatureNew feature or request
Description
@i-am-sijia
i-am-sijia
opened on Jun 12, 2025
ActivitySim relies on numerous third-party Python packages, i.e., its dependencies. ActivitySim users occasionally report installation and/or runtime failures due to these dependencies (#919, #921). This typically happens when one or more of the dependencies is updated to a new version. Unless explicitly specified, ActivitySim looks for and installs the latest versions of its dependencies. The latest versions of dependencies can conflict with each other and/or have API updates that are no longer backward compatible with ActivitySim.
ActivitySim’s current solution is to specify version ranges for select dependencies, see here for an example. When conflicts arise, additional dependencies are added to this list. This approach has been effective, but is passive and sub-optimal: new conflicts are bound to arise. Recently, users have not been able to install and run ActivitySim because one of its second order dependencies (i.e., a dependency of a dependency), “multimethod”, has a new version that is not compatible with ActivitySim (#919). Therefore, the ActivitySim Consortium desires a more proactive solution.
This is a common problem in Python and a common solution is to “lock” Python dependencies to create “deterministic” builds (i.e., specify versions of each dependency, including dependencies of dependencies, used by ActivitySim). Locking Python dependencies improves consistency, reproducibility, and stability across environments for development, testing, and production.
There are many tools available for locking Python dependencies. With tools like uv, pdm, or poetry, the exact versions of all dependencies ActivitySim requires are specified, reducing the chances of unexpected issues caused by updates or version mismatches.
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