From 3715e269b995a3c09c6fc92fc5137df9285b8246 Mon Sep 17 00:00:00 2001
From: Harald Hoyer <harald@hoyer.xyz>
Date: Thu, 21 May 2026 23:59:58 +0200
Subject: [PATCH] fix(opencode): disable auto-format on save

opencode reformats files in the background after each write, which
desyncs the model's view of a file between edits and breaks follow-up
edits whose old_string no longer matches. Set formatter = false; the
formatter tools stay on PATH via home.packages for manual use.
---
 modules/home/cli-apps/opencode/default.nix | 69 ++--------------------
 1 file changed, 4 insertions(+), 65 deletions(-)

diff --git a/modules/home/cli-apps/opencode/default.nix b/modules/home/cli-apps/opencode/default.nix
index 6f463e7..fd0ca99 100644
--- a/modules/home/cli-apps/opencode/default.nix
+++ b/modules/home/cli-apps/opencode/default.nix
@@ -11,74 +11,13 @@ let
 
   cfg = config.metacfg.cli-apps.opencode;
 
-  # Formatters opencode runs on save, each pinned to its exact store path.
-  formatters = {
-    nixfmt = {
-      command = [
-        (lib.getExe pkgs.nixfmt-rfc-style)
-        "$FILE"
-      ];
-      extensions = [ ".nix" ];
-    };
-    prettier = {
-      command = [
-        (lib.getExe pkgs.nodePackages.prettier)
-        "--write"
-        "$FILE"
-      ];
-      extensions = [
-        ".md"
-        ".yaml"
-        ".yml"
-        ".json"
-        ".css"
-        ".html"
-        ".js"
-        ".ts"
-        ".jsx"
-        ".tsx"
-      ];
-    };
-    shfmt = {
-      command = [
-        (lib.getExe pkgs.shfmt)
-        "-w"
-        "$FILE"
-      ];
-      extensions = [
-        ".sh"
-        ".bash"
-      ];
-    };
-    ruff = {
-      command = [
-        (lib.getExe pkgs.ruff)
-        "format"
-        "$FILE"
-      ];
-      extensions = [ ".py" ];
-    };
-    taplo = {
-      command = [
-        (lib.getExe pkgs.taplo)
-        "format"
-        "$FILE"
-      ];
-      extensions = [ ".toml" ];
-    };
-    stylua = {
-      command = [
-        (lib.getExe pkgs.stylua)
-        "$FILE"
-      ];
-      extensions = [ ".lua" ];
-    };
-  };
-
   opencodeConfig = {
     "$schema" = "https://opencode.ai/config.json";
     lsp = true;
-    formatter = formatters;
+    # Auto-format on save is disabled: opencode reformats files between the
+    # model's edits, which desyncs its view and breaks follow-up edits. The
+    # formatters remain available on PATH (home.packages) for manual use.
+    formatter = false;
     disabled_providers = [ "opencode" ];
     provider.halo = {
       npm = "@ai-sdk/openai-compatible";