{"id":49016,"date":"2025-08-25T08:41:35","date_gmt":"2025-08-25T12:41:35","guid":{"rendered":"https:\/\/mjtsai.com\/blog\/?p=49016"},"modified":"2026-04-29T10:46:22","modified_gmt":"2026-04-29T14:46:22","slug":"retcon-1-4","status":"publish","type":"post","link":"https:\/\/mjtsai.com\/blog\/2025\/08\/25\/retcon-1-4\/","title":{"rendered":"Retcon 1.4"},"content":{"rendered":"<p><a href=\"https:\/\/retcon.app\/releases\">Nathan Manceaux-Panot<\/a>:<\/p>\n<blockquote cite=\"https:\/\/retcon.app\/releases\">\n<p>Enjoy staggering performance improvements. Every last part of the app has been thoroughly tuned: Retcon is now incredibly responsive, and easily handles Git histories with hundreds of thousands of commits.<\/p>\n<p>No compromise was made to reach these speeds: Retcon still transparently preserves your working directory and stage, offers pervasive undo, a combined stage, and the ability to rewrite history even when conflicts are pending.<\/p>\n<\/blockquote>\n\n<p>I kind of love seeing release notes that are like: no new features, we just fixed some bugs and made it 35&#xD7; faster.<\/p>\n\n<p>Previously:<\/p>\n<ul>\n<li><a href=\"https:\/\/mjtsai.com\/blog\/2025\/02\/20\/retcon-1-2\/\">Retcon 1.2<\/a><\/li>\n<\/ul>\n\n<p id=\"retcon-1-4-update-2026-04-29\">Update (<a href=\"#retcon-1-4-update-2026-04-29\">2026-04-29<\/a>): <a href=\"https:\/\/pending.design\/making-retcon-fast-caches\/\">Nathan Manceaux-Panot<\/a> (<a href=\"https:\/\/mas.to\/@Cykelero\/115378509816412641\">Mastodon<\/a>):<\/p>\n<blockquote cite=\"https:\/\/pending.design\/making-retcon-fast-caches\/\">\n<p>Well, there&rsquo;s no single thing. Months of work resulted in numerous, surprisingly diverse optimizations; some expected, some eyebrow-raising. Despite that variety, however, one kind of optimization ended up the most common by far: caches.<\/p>\n<p>[&#8230;]<\/p>\n<p>It&rsquo;s a no-brainer to cache the output of this expensive measuring process, as a given hunk will often stay the exact same when the diff view is refreshed. Here&rsquo;s the tricky part, though: what does it mean to be the <em>exact same<\/em>? If the hunk&rsquo;s text remains unchanged, but the window becomes wider, then we should redo the measurement&mdash;more horizontal space means less wrapping. If one of the hunk&rsquo;s neighbors changes in content, we ostensibly don&rsquo;t need to reflow the unchanged hunk itself&mdash;unless the neighbor&rsquo;s <em>line numbers<\/em> are now different, since these dictate the width of the line number gutter, which is shared by all of a file&rsquo;s hunks. So many variables to take into account, coming from such distinct sources!<\/p>\n<\/blockquote>\n\n<p>Previously:<\/p>\n<ul>\n<li><a href=\"https:\/\/mjtsai.com\/blog\/2025\/08\/15\/textkit-2-the-promised-land\/\">TextKit 2: The Promised Land<\/a><\/li>\n<\/ul>","protected":false},"excerpt":{"rendered":"<p>Nathan Manceaux-Panot: Enjoy staggering performance improvements. Every last part of the app has been thoroughly tuned: Retcon is now incredibly responsive, and easily handles Git histories with hundreds of thousands of commits. No compromise was made to reach these speeds: Retcon still transparently preserves your working directory and stage, offers pervasive undo, a combined stage, [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"apple_news_api_created_at":"2025-08-25T12:41:38Z","apple_news_api_id":"7e8e1464-1445-432e-b167-d89d2a49a35e","apple_news_api_modified_at":"2026-04-29T14:46:26Z","apple_news_api_revision":"AAAAAAAAAAAAAAAAAAAAAA==","apple_news_api_share_url":"https:\/\/apple.news\/Afo4UZBRFQy6xZ9idKkmjXg","apple_news_coverimage":0,"apple_news_coverimage_caption":"","apple_news_is_hidden":false,"apple_news_is_paid":false,"apple_news_is_preview":false,"apple_news_is_sponsored":false,"apple_news_maturity_rating":"","apple_news_metadata":"\"\"","apple_news_pullquote":"","apple_news_pullquote_position":"","apple_news_slug":"","apple_news_sections":"\"\"","apple_news_suppress_video_url":false,"apple_news_use_image_component":false,"footnotes":""},"categories":[2],"tags":[75,377,30,32,2598,138,71,2480,591,376],"class_list":["post-49016","post","type-post","status-publish","format-standard","hentry","category-technology","tag-developertool","tag-git","tag-mac","tag-macapp","tag-macos-15-sequoia","tag-optimization","tag-programming","tag-retcon","tag-text-kit","tag-versioncontrol"],"apple_news_notices":[],"_links":{"self":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts\/49016","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/comments?post=49016"}],"version-history":[{"count":2,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts\/49016\/revisions"}],"predecessor-version":[{"id":51750,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/posts\/49016\/revisions\/51750"}],"wp:attachment":[{"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/media?parent=49016"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/categories?post=49016"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mjtsai.com\/blog\/wp-json\/wp\/v2\/tags?post=49016"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}