src-tauri/src/git.rs

@@ -1040,6 +1040,63 @@ pub fn commit(path: String, message: String) -> Result<GitStatus, String> {
     status_for_repo(&repo)
 }
 
+#[tauri::command]
+pub fn amend_commit(path: String, message: Option<String>) -> Result<GitStatus, String> {
+    let repo = resolve_repo(&path)?;
+    if verify_commit(&repo, "HEAD").is_err() {
+        return Err("There is no commit to amend.".to_string());
+    }
+
+    let current_status = status_for_repo(&repo)?;
+    if has_unresolved_conflicts(&current_status) {
+        return Err("Merge conflicts must be resolved before you can commit.".to_string());
+    }
+
+    let message = message
+        .map(|message| message.trim().to_string())
+        .filter(|message| !message.is_empty());
+
+    match message {
+        Some(message) => {
+            run_git(&repo, ["commit", "--amend", "-m", message.as_str()])?;
+        }
+        None => {
+            run_git(&repo, ["commit", "--amend", "--no-edit"])?;
+        }
+    }
+
+    status_for_repo(&repo)
+}
+
+#[tauri::command]
+pub fn last_commit_message(path: String) -> Result<Option<String>, String> {
+    let repo = resolve_repo(&path)?;
+    if verify_commit(&repo, "HEAD").is_err() {
+        return Ok(None);
+    }
+
+    let output = run_git(&repo, ["log", "-1", "--format=%B", "HEAD"])?;
+    let message = String::from_utf8_lossy(&output).trim_end().to_string();
+    Ok(if message.is_empty() { None } else { Some(message) })
+}
+
+#[tauri::command]
+pub fn undo_last_commit(path: String) -> Result<GitStatus, String> {
+    let repo = resolve_repo(&path)?;
+    if verify_commit(&repo, "HEAD").is_err() {
+        return Err("There is no commit to undo.".to_string());
+    }
+    if verify_commit(&repo, "HEAD~1").is_err() {
+        return Err("This is the first commit; there is nothing to undo to.".to_string());
+    }
+
+    // Mixed reset: moves HEAD back one commit and unstages the difference, but
+    // leaves the working tree files untouched, so the undone commit's changes
+    // reappear as ordinary uncommitted changes instead of being discarded.
+    run_git(&repo, ["reset", "HEAD~1"])?;
+    status_for_repo(&repo)
+}
+
 #[tauri::command]
 pub fn pull(
     path: String,

src-tauri/src/main.rs

@@ -5,18 +5,19 @@ mod git;
 
 use badge::set_sync_badge;
 use git::{
-    SearchCancellationState, apply_file_patch, cancel_code_search, cancel_file_history,
-    checkout_branch, cherry_pick_abort, cherry_pick_commit, cherry_pick_continue,
-    clone_repository, commit, commit_ai_generate, commit_ai_load, commit_ai_local_models,
-    commit_ai_status, compare_commits, compare_file_to_head, compare_file_to_parent,
-    create_branch, create_tag, cred_delete, cred_load, cred_save, delete_branch, delete_tag,
-    diff_file_against_working_tree, fetch, get_file_patch, get_remote_url, get_status,
-    list_branches, list_commits, list_file_history, list_repository_files, list_stashes,
-    list_tags, merge_branch, open_repo_in_explorer, open_repository, open_repository_bundle,
-    open_repository_file, pull, push, push_tag, read_conflict, rebase_abort, rebase_branch,
-    rebase_continue, rename_branch, resolve_conflict, resolve_conflict_side,
-    restore_file_from_commit, restore_files, restore_to_commit, search_code_introductions,
-    stage_files, stash_apply, stash_drop, stash_pop, stash_push, unstage_files,
+    SearchCancellationState, amend_commit, apply_file_patch, cancel_code_search,
+    cancel_file_history, checkout_branch, cherry_pick_abort, cherry_pick_commit,
+    cherry_pick_continue, clone_repository, commit, commit_ai_generate, commit_ai_load,
+    commit_ai_local_models, commit_ai_status, compare_commits, compare_file_to_head,
+    compare_file_to_parent, create_branch, create_tag, cred_delete, cred_load, cred_save,
+    delete_branch, delete_tag, diff_file_against_working_tree, fetch, get_file_patch,
+    get_remote_url, get_status, last_commit_message, list_branches, list_commits,
+    list_file_history, list_repository_files, list_stashes, list_tags, merge_branch,
+    open_repo_in_explorer, open_repository, open_repository_bundle, open_repository_file, pull,
+    push, push_tag, read_conflict, rebase_abort, rebase_branch, rebase_continue, rename_branch,
+    resolve_conflict, resolve_conflict_side, restore_file_from_commit, restore_files,
+    restore_to_commit, search_code_introductions, stage_files, stash_apply, stash_drop,
+    stash_pop, stash_push, undo_last_commit, unstage_files,
 };
 
 fn main() {
@@ -54,6 +55,9 @@ fn main() {
             get_file_patch,
             apply_file_patch,
             commit,
+            amend_commit,
+            undo_last_commit,
+            last_commit_message,
             commit_ai_status,
             commit_ai_load,
             commit_ai_local_models,

src/App.svelte

@@ -28,6 +28,7 @@
   import UpdateToast from "./lib/components/UpdateToast.svelte";
 
   import {
+    amendCommit,
     checkoutBranch,
     cherryPickAbort,
     cherryPickCommit,
@@ -50,6 +51,7 @@
     compareFileToParent,
     fetchRemote,
     getStatus,
+    lastCommitMessage,
     listBranches,
     listStashes,
     listTags,
@@ -85,6 +87,7 @@
     stashDrop,
     stashPop,
     stashPush,
+    undoLastCommit,
     unstageFiles,
   } from "./lib/git";
 
@@ -182,6 +185,8 @@
   let activeFileHistoryRequestId = "";
   let lastFileHistoryHeadHash = "";
   let commitMessage = "";
+  let amendMode = false;
+  let preAmendDraftMessage = "";
   let lastLocalAiGeneratedMessage = "";
   let commitAiPhase: CommitAiPhase = "idle";
   let commitAiGenerating = false;
@@ -270,7 +275,18 @@
   $: hasConflicts = conflictedFiles.length > 0;
   $: rebaseInProgress = status?.rebase_in_progress ?? false;
   $: cherryPickInProgress = status?.cherry_pick_in_progress ?? false;
-  $: canCommit = hasRepository && stagedCount > 0 && commitMessage.trim().length > 0 && !hasConflicts && !rebaseInProgress && !cherryPickInProgress && !isBusy;
+  // Amending/undoing is only offered while the last commit hasn't reached a
+  // remote yet: no upstream at all, or the branch is still ahead of it.
+  $: canAmend = hasRepository && commits.length > 0 && !hasConflicts && !rebaseInProgress && !cherryPickInProgress
+    && (!status?.upstream || (status?.ahead ?? 0) > 0);
+  // Safety net: if the last commit gets pushed elsewhere (or a conflict/rebase starts)
+  // while amend mode is active, drop out of it instead of leaving a stale, hidden toggle.
+  $: if (!canAmend && amendMode) {
+    amendMode = false;
+    commitMessage = preAmendDraftMessage;
+    preAmendDraftMessage = "";
+  }
+  $: canCommit = hasRepository && (amendMode || stagedCount > 0) && commitMessage.trim().length > 0 && !hasConflicts && !rebaseInProgress && !cherryPickInProgress && !isBusy;
   $: commitBlockReason = rebaseInProgress
     ? "A rebase is in progress. Resolve conflicts and use Rebase continue or abort the rebase."
     : cherryPickInProgress
@@ -1871,7 +1887,8 @@
 
   async function commitChanges() {
     const message = commitMessage.trim();
-    if (!message || !activeRepoPath) return;
+    if (!activeRepoPath) return;
+    if (!amendMode && !message) return;
     if (hasConflicts) {
       errorMessage = "Resolve all conflicts before committing.";
       return;
@@ -1884,6 +1901,22 @@
       errorMessage = "A cherry-pick is in progress. Use Cherry-pick continue or abort it.";
       return;
     }
+
+    if (amendMode) {
+      await runOperation("Amending", async () => {
+        applyStatus(await amendCommit(activeRepoPath, message));
+        commitMessage = "";
+        amendMode = false;
+        preAmendDraftMessage = "";
+        lastLocalAiGeneratedMessage = "";
+        await refreshBranchList(activeRepoPath);
+        await refreshCommitHistory(activeRepoPath);
+        await refreshExplorerFiles(activeRepoPath);
+        await refreshFileHistory(activeRepoPath);
+      });
+      return;
+    }
+
     await runOperation("Committing", async () => {
       applyStatus(await commit(activeRepoPath, message));
       commitMessage = "";
@@ -1895,6 +1928,50 @@
     });
   }
 
+  // Only offered when the last commit hasn't reached a remote yet (no upstream,
+  // or the branch is ahead of it) — amending/undoing a pushed commit rewrites
+  // history other clones already have, which needs a force-push to reconcile.
+  async function toggleAmendMode(checked: boolean) {
+    if (!activeRepoPath || isBusy) return;
+    if (!checked) {
+      amendMode = false;
+      commitMessage = preAmendDraftMessage;
+      preAmendDraftMessage = "";
+      return;
+    }
+    if (!canAmend) return;
+
+    try {
+      const message = await lastCommitMessage(activeRepoPath);
+      preAmendDraftMessage = commitMessage;
+      commitMessage = message ?? "";
+      amendMode = true;
+    } catch (error) {
+      errorMessage = errorToMessage(error);
+    }
+  }
+
+  async function undoLastCommitChange() {
+    if (!activeRepoPath || !canAmend || isBusy) return;
+    const confirmed = window.confirm(
+      "Undo the last commit?\n\nIts changes come back as uncommitted changes in the working tree — nothing is discarded.",
+    );
+    if (!confirmed) return;
+
+    await runOperation("Undoing last commit", async () => {
+      applyStatus(await undoLastCommit(activeRepoPath));
+      if (amendMode) {
+        amendMode = false;
+        commitMessage = preAmendDraftMessage;
+        preAmendDraftMessage = "";
+      }
+      await refreshBranchList(activeRepoPath);
+      await refreshCommitHistory(activeRepoPath);
+      await refreshExplorerFiles(activeRepoPath);
+      await refreshFileHistory(activeRepoPath);
+    });
+  }
+
   // ── Commit restore ─────────────────────────────────────────────────────────
 
   async function restoreCommit(target: GitCommit) {
@@ -2575,10 +2652,14 @@
             commitAiProvider={aiSettings.provider}
             {commitAiPhase}
             {commitAiGenerating}
+            {canAmend}
+            {amendMode}
             onCommit={commitChanges}
             onCommitMessageChange={updateCommitMessage}
             onGenerateCommitMessage={generateCommitMessageWithAi}
             onOpenAiSettings={() => { aiSettingsOpen = true; }}
+            onToggleAmend={toggleAmendMode}
+            onUndoLastCommit={undoLastCommitChange}
           />
         </div>
       </section>

src/app.css

@@ -1807,6 +1807,29 @@
     resize: none;
     overflow: auto;
   }
+  .commit-amend-row {
+    display: flex;
+    align-items: center;
+    justify-content: space-between;
+    flex: 0 0 auto;
+    gap: 8px;
+    min-width: 0;
+  }
+  .commit-amend-toggle {
+    display: flex;
+    align-items: center;
+    gap: 6px;
+    color: var(--color-ink-dim);
+    font-size: 12px;
+    white-space: nowrap;
+  }
+  .commit-undo-button {
+    flex: 0 0 auto;
+    min-height: 26px;
+    padding: 0 8px;
+    font-size: 11px;
+  }
+
   .commit-actions-row {
     display: flex;
     flex: 0 0 auto;

src/lib/components/CommitPanel.svelte

@@ -1,5 +1,5 @@
 <script lang="ts">
-  import { Check, LoaderCircle, Settings, Sparkles } from "@lucide/svelte";
+  import { Check, LoaderCircle, RotateCcw, Settings, Sparkles } from "@lucide/svelte";
   import type { CommitAiPhase, CommitAiProvider } from "../types";
 
   interface Props {
@@ -13,10 +13,14 @@
     commitAiProvider: CommitAiProvider;
     commitAiPhase: CommitAiPhase;
     commitAiGenerating: boolean;
+    canAmend: boolean;
+    amendMode: boolean;
     onCommit: () => void;
     onCommitMessageChange: (msg: string) => void;
     onGenerateCommitMessage: () => void;
     onOpenAiSettings: () => void;
+    onToggleAmend: (checked: boolean) => void;
+    onUndoLastCommit: () => void;
   }
 
   let {
@@ -30,10 +34,14 @@
     commitAiProvider = "local",
     commitAiPhase = "idle",
     commitAiGenerating = false,
+    canAmend = false,
+    amendMode = false,
     onCommit = () => {},
     onCommitMessageChange = () => {},
     onGenerateCommitMessage = () => {},
     onOpenAiSettings = () => {},
+    onToggleAmend = () => {},
+    onUndoLastCommit = () => {},
   }: Props = $props();
 
   function handleSubmit(event: SubmitEvent) {
@@ -77,14 +85,37 @@
     {#if commitBlockReason}
       <p class="commit-block-reason">{commitBlockReason}</p>
     {/if}
+    {#if canAmend}
+      <div class="commit-amend-row">
+        <label class="commit-amend-toggle">
+          <input
+            type="checkbox"
+            checked={amendMode}
+            disabled={isBusy}
+            onchange={(e) => onToggleAmend((e.target as HTMLInputElement).checked)}
+          />
+          Amend last commit
+        </label>
+        <button
+          class="btn-secondary commit-undo-button"
+          type="button"
+          onclick={onUndoLastCommit}
+          disabled={isBusy}
+          title="Undo the last commit — its changes come back as uncommitted changes (not pushed yet, so safe)"
+        >
+          <RotateCcw size={13} aria-hidden="true" />
+          Undo last commit
+        </button>
+      </div>
+    {/if}
     <div class="commit-actions-row flex-shrink-0">
-      <button class="btn-primary flex-1" type="submit" disabled={!canCommit} title={commitBlockReason || "Commit staged changes"}>
-        {#if operation === "Committing"}
+      <button class="btn-primary flex-1" type="submit" disabled={!canCommit} title={commitBlockReason || (amendMode ? "Amend the last commit" : "Commit staged changes")}>
+        {#if operation === "Committing" || operation === "Amending"}
           <LoaderCircle class="spin" size={16} aria-hidden="true" />
         {:else}
           <Check size={16} aria-hidden="true" />
         {/if}
-        Commit
+        {amendMode ? "Amend" : "Commit"}
       </button>
       <button
         class="btn-secondary commit-ai-button"

src/lib/git.ts

@@ -171,6 +171,18 @@ export function commit(path: string, message: string): Promise<GitStatus> {
   return invoke<GitStatus>("commit", { path, message });
 }
 
+export function amendCommit(path: string, message?: string): Promise<GitStatus> {
+  return invoke<GitStatus>("amend_commit", { path, message: message?.trim() ? message.trim() : null });
+}
+
+export function lastCommitMessage(path: string): Promise<string | null> {
+  return invoke<string | null>("last_commit_message", { path });
+}
+
+export function undoLastCommit(path: string): Promise<GitStatus> {
+  return invoke<GitStatus>("undo_last_commit", { path });
+}
+
 export function stashPush(
   path: string,
   message?: string,