diff --git a/forwardport/models/project.py b/forwardport/models/project.py
index 0031b61b..f26ebfd5 100644
--- a/forwardport/models/project.py
+++ b/forwardport/models/project.py
@@ -346,7 +346,7 @@ class PullRequests(models.Model):
                 '--merge-base', commits[0]['parents'][0]['sha'],
                 target_branch.name,
                 root.head,
-            )
+            ).stdout.decode().splitlines(keepends=False)[0]
             # if there was a single commit, reuse its message when committing
             # the conflict
             if len(commits) == 1:
@@ -362,10 +362,28 @@ stderr:
 {err}
 """
 
+            # if a file is modified by the original PR and added by the forward
+            # port / conflict it's a modify/delete conflict: the file was
+            # deleted in the target branch, and the update (modify) in the
+            # original PR causes it to be added back
+            original_modified = set(conf.diff(
+                "--diff-filter=M", "--name-only",
+                "--merge-base", root.target.name,
+                root.head,
+            ).stdout.decode().splitlines(keepends=False))
+            conflict_added = set(conf.diff(
+                "--diff-filter=A", "--name-only",
+                target_branch.name,
+                tree,
+            ).stdout.decode().splitlines(keepends=False))
+            if modify_delete := (conflict_added & original_modified):
+                # rewrite the tree with conflict markers added to modify/deleted blobs
+                tree = conf.modify_delete(tree, modify_delete)
+
             target_head = source.stdout().rev_parse(f"refs/heads/{target_branch.name}")\
                 .stdout.decode().strip()
             commit = conf.commit_tree(
-                tree=tree.stdout.decode().splitlines(keepends=False)[0],
+                tree=tree,
                 parents=[target_head],
                 message=str(msg),
                 author=author,
diff --git a/forwardport/tests/test_conflicts.py b/forwardport/tests/test_conflicts.py
index 3c0bbda6..f6e23bbf 100644
--- a/forwardport/tests/test_conflicts.py
+++ b/forwardport/tests/test_conflicts.py
@@ -262,7 +262,7 @@ def test_massive_conflict(env, config, make_repo):
 
 
 def test_conflict_deleted(env, config, make_repo):
-    prod, other = make_basic(env, config, make_repo)
+    prod, other = make_basic(env, config, make_repo, statuses="default")
     # remove f from b
     with prod:
         prod.make_commits(
@@ -277,18 +277,12 @@ def test_conflict_deleted(env, config, make_repo):
             ref='heads/conflicting'
         )
         pr = prod.make_pr(target='a', head='conflicting')
-        prod.post_status(p_0, 'success', 'legal/cla')
-        prod.post_status(p_0, 'success', 'ci/runbot')
+        prod.post_status(p_0, 'success')
         pr.post_comment('hansen r+', config['role_reviewer']['token'])
 
     env.run_crons()
     with prod:
-        prod.post_status('staging.a', 'success', 'legal/cla')
-        prod.post_status('staging.a', 'success', 'ci/runbot')
-
-    env.run_crons()
-    # wait a bit for PR webhook... ?
-    time.sleep(5)
+        prod.post_status('staging.a', 'success')
     env.run_crons()
 
     # should have created a new PR
@@ -300,9 +294,14 @@ def test_conflict_deleted(env, config, make_repo):
         'g': 'c',
     }
     assert pr1.state == 'opened'
-    # NOTE: no actual conflict markers because pr1 essentially adds f de-novo
     assert prod.read_tree(prod.commit(pr1.head)) == {
-        'f': 'xxx',
+        'f': matches("""\
+<<<\x3c<<< $$
+||||||| $$
+=======
+xxx
+>>>\x3e>>> $$
+"""),
         'g': 'c',
     }
 
@@ -333,6 +332,89 @@ def test_conflict_deleted(env, config, make_repo):
     }
     assert pr1.state == 'opened', "state should be open still"
 
+
+def test_conflict_deleted_deep(env, config, make_repo):
+    """ Same as the previous one but files are deeper than toplevel, and we only
+    want to see if the conflict post-processing works.
+    """
+    # region: setup
+    prod = make_repo("test")
+    env['runbot_merge.events_sources'].create({'repository': prod.name})
+    with prod:
+        [a, b] = prod.make_commits(
+            None,
+            Commit("a", tree={
+                "foo/bar/baz": "1",
+                "foo/bar/qux": "1",
+                "corge/grault": "1",
+            }),
+            Commit("b", tree={"foo/bar/qux": "2"}, reset=True),
+        )
+        prod.make_ref("heads/a", a)
+        prod.make_ref("heads/b", b)
+
+    project = env['runbot_merge.project'].create({
+        'name': "test",
+        'github_token': config['github']['token'],
+        'github_prefix': 'hansen',
+        'fp_github_token': config['github']['token'],
+        'fp_github_name': 'herbert',
+        'branch_ids': [
+            (0, 0, {'name': 'a', 'sequence': 100}),
+            (0, 0, {'name': 'b', 'sequence': 80}),
+        ],
+        "repo_ids": [
+            (0, 0, {
+                'name': prod.name,
+                'required_statuses': "default",
+                'fp_remote_target': prod.fork().name,
+                'group_id': False,
+            })
+        ]
+    })
+    env['res.partner'].search([
+        ('github_login', '=', config['role_reviewer']['user'])
+    ]).write({
+        'review_rights': [(0, 0, {'repository_id': project.repo_ids.id, 'review': True})]
+    })
+    # endregion
+
+    with prod:
+        prod.make_commits(
+            'a',
+            Commit("c", tree={
+                "foo/bar/baz": "2",
+                "corge/grault": "insert funny number",
+            }),
+            ref="heads/conflicting",
+        )
+        pr = prod.make_pr(target='a', head='conflicting')
+        prod.post_status("conflicting", "success")
+        pr.post_comment("hansen r+", config['role_reviewer']['token'])
+    env.run_crons()
+
+    with prod:
+        prod.post_status('staging.a', 'success')
+    env.run_crons()
+    _, pr1 = env['runbot_merge.pull_requests'].search([], order='number')
+    assert prod.read_tree(prod.commit(pr1.head), recursive=True) == {
+        "foo/bar/qux": "2",
+        "foo/bar/baz": """\
+<<<<<<< HEAD
+||||||| MERGE BASE
+=======
+2
+>>>>>>> FORWARD PORTED
+""",
+        "corge/grault": """\
+<<<<<<< HEAD
+||||||| MERGE BASE
+=======
+insert funny number
+>>>>>>> FORWARD PORTED
+"""
+    }, "the conflicting file should have had conflict markers fixed in"
+
 def test_multiple_commits_same_authorship(env, config, make_repo):
     """ When a PR has multiple commits by the same author and its
     forward-porting triggers a conflict, the resulting (squashed) conflict
@@ -436,13 +518,13 @@ def test_multiple_commits_different_authorship(env, config, make_repo, users, ro
         "author set to the bot but an empty email"
     assert get(c.committer) == (bot, '')
 
-    assert re.match(r'''<<<\x3c<<< HEAD
+    assert prod.read_tree(c)['g'] == matches('''<<<\x3c<<< b
 b
-|||||||| parent of [\da-f]{7,}.*
+||||||| $$
 =======
 2
->>>\x3e>>> [\da-f]{7,}.*
-''', prod.read_tree(c)['g'])
+>>>\x3e>>> $$
+''')
 
     # I'd like to fix the conflict so everything is clean and proper *but*
     # github's API apparently rejects creating commits with an empty email.
@@ -459,7 +541,7 @@ b
 
     assert pr2.comments == [
         seen(env, pr2, users),
-        (users['user'], matches('@%s @%s $$CONFLICT' % (users['user'], users['reviewer']))),
+        (users['user'], matches('@%(user)s @%(reviewer)s $$CONFLICT' % users)),
         (users['reviewer'], 'hansen r+'),
         (users['user'], f"@{users['user']} @{users['reviewer']} unable to stage: "
                         "All commits must have author and committer email, "
diff --git a/runbot_merge/git.py b/runbot_merge/git.py
index caaa6e5d..d9937329 100644
--- a/runbot_merge/git.py
+++ b/runbot_merge/git.py
@@ -6,7 +6,8 @@ import pathlib
 import resource
 import stat
 import subprocess
-from typing import Optional, TypeVar, Union, Sequence, Tuple, Dict
+from operator import methodcaller
+from typing import Optional, TypeVar, Union, Sequence, Tuple, Dict, Iterable
 
 from odoo.tools.appdirs import user_cache_dir
 from .github import MergeError, PrCommit
@@ -245,6 +246,47 @@ class Repo:
             *itertools.chain.from_iterable(('-p', p) for p in parents),
         )
 
+
+    def modify_delete(self, tree: str, files: Iterable[str]) -> str:
+        """Updates ``files`` in ``tree`` to add conflict markers to show them
+        as being modify/delete-ed, rather than have only the original content.
+
+        This is because having just content in a valid file is easy to miss,
+        causing file resurrections as they get committed rather than re-removed.
+
+        TODO: maybe extract the diff information compared to before they were removed? idk
+        """
+        # FIXME: either ignore or process binary files somehow (how does git show conflicts in binary files?)
+        repo = self.stdout().with_config(stderr=None, text=True, check=False, encoding="utf-8")
+        for f in files:
+            contents = repo.cat_file("-p", f"{tree}:{f}").stdout
+            # decorate the contents as if HEAD and BASE are empty
+            oid = repo\
+                .with_config(input=f"""\
+<<<\x3c<<< HEAD
+||||||| MERGE BASE
+=======
+{contents}
+>>>\x3e>>> FORWARD PORTED
+""")\
+                .hash_object("-w", "--stdin", "--path", f)\
+                .stdout.strip()
+
+            # we need to rewrite every tree from the parent of `f`
+            while f:
+                f, _, local = f.rpartition("/")
+                # tree to update, `{tree}:` works as an alias for tree
+                lstree = repo.ls_tree(f"{tree}:{f}").stdout.splitlines(keepends=False)
+                new_tree = "".join(
+                    # tab before name is critical to the format
+                    f"{mode} {typ} {oid if name == local else sha}\t{name}\n"
+                    for mode, typ, sha, name in map(methodcaller("split", None, 3), lstree)
+                )
+                oid = repo.with_config(input=new_tree, check=True).mktree().stdout.strip()
+            tree = oid
+        return tree
+
+
 def check(p: subprocess.CompletedProcess) -> subprocess.CompletedProcess:
     if not p.returncode:
         return p