diff --git a/lua/git/diff.lua b/lua/git/diff.lua
index b3caeab..0369907 100644
--- a/lua/git/diff.lua
+++ b/lua/git/diff.lua
@@ -81,17 +81,13 @@ local function uri_split(opts, buf, rev)
     local object = require("git.object")
 
     if opts.rev and opts.rev:find(":", 1, true) then
-        local content = util.exec(
-            { "git", "cat-file", "-p", opts.rev },
-            { cwd = r.worktree, silent = true }
-        )
-        if not content then
+        if not r:rev_parse(opts.rev, true) then
             util.error("invalid rev: %s", opts.rev)
             return
         end
         place_pair(
             buf,
-            object.buf_for(r, Revision.parse(opts.rev), content),
+            object.buf_for(r, Revision.parse(opts.rev)),
             false,
             opts.vertical
         )
@@ -123,15 +119,11 @@ local function uri_split(opts, buf, rev)
     local m = mapping[rev.stage]
         or { Revision.new({ stage = 0, path = rev.path }), true }
     local other_rev, left = m[1], m[2]
-    local content = util.exec(
-        { "git", "cat-file", "-p", other_rev:format() },
-        { cwd = r.worktree, silent = true }
-    )
-    if not content then
+    if not r:rev_parse(other_rev:format(), true) then
         util.error("invalid rev: %s", other_rev:format())
         return
     end
-    place_pair(buf, object.buf_for(r, other_rev, content), left, opts.vertical)
+    place_pair(buf, object.buf_for(r, other_rev), left, opts.vertical)
 end
 
 ---@class ow.Git.Diff.SplitOpts
@@ -172,15 +164,11 @@ function M.split(opts)
     else
         rev = Revision.new({ base = opts.rev, path = rel })
     end
-    local content = util.exec(
-        { "git", "cat-file", "-p", rev:format() },
-        { cwd = r.worktree, silent = true }
-    )
-    if not content then
+    if not r:rev_parse(rev:format(), true) then
         util.error("invalid rev: %s", rev:format())
         return
     end
-    local buf = require("git.object").buf_for(r, rev, content)
+    local buf = require("git.object").buf_for(r, rev)
     place_pair(buf, cur_buf, true, opts.vertical)
 end
 
diff --git a/lua/git/init.lua b/lua/git/init.lua
index d75c2e8..eed4b28 100644
--- a/lua/git/init.lua
+++ b/lua/git/init.lua
@@ -71,7 +71,7 @@ function M.init()
         pattern = "git://*",
         group = group,
         callback = function(args)
-            require("git.object").read_uri(args.buf, { force = true })
+            require("git.object").read_uri(args.buf)
         end,
     })
 
diff --git a/lua/git/log_view.lua b/lua/git/log_view.lua
index 803dfbe..f813e4f 100644
--- a/lua/git/log_view.lua
+++ b/lua/git/log_view.lua
@@ -49,10 +49,10 @@ local function fetch(worktree, max_count)
 end
 
 ---@param buf integer
-local function populate(buf)
-    local r = repo.resolve(buf)
-    local state = r and r:state(buf)
-    if not r or not state then
+---@param r ow.Git.Repo
+local function populate(buf, r)
+    local state = r:state(buf)
+    if not state then
         return
     end
     local stdout = fetch(r.worktree, state.log_max_count)
@@ -110,7 +110,7 @@ function M.read_uri(buf)
     end
 
     attach_dispatch(buf)
-    populate(buf)
+    populate(buf, r)
 end
 
 ---@class ow.Git.Log.OpenOpts
@@ -144,7 +144,7 @@ function M.open(opts)
     end
 
     if was_loaded then
-        populate(buf)
+        populate(buf, r)
     end
 end
 
@@ -183,6 +183,6 @@ function M.complete_glog(arg_lead)
     return matches
 end
 
-repo.on_uri_refresh(M.URI_PREFIX, M.read_uri)
+repo.on_uri_refresh(M.URI_PREFIX, populate)
 
 return M
diff --git a/lua/git/object.lua b/lua/git/object.lua
index 1f9bcf8..40bbf33 100644
--- a/lua/git/object.lua
+++ b/lua/git/object.lua
@@ -71,6 +71,20 @@ local function is_zero(sha)
     return sha == nil or sha:match("^0+$") ~= nil
 end
 
+---@param rev ow.Git.Revision
+---@return boolean
+local function is_immutable_rev(rev)
+    if rev.stage ~= nil then
+        return false
+    end
+    local base = rev.base
+    if not base then
+        return false
+    end
+    local stripped = base:gsub("%^%b{}", ""):gsub("[%^~]%d*", "")
+    return stripped:match("^%x+$") ~= nil and #stripped >= 7
+end
+
 ---@param buf integer
 ---@param r ow.Git.Repo
 ---@param path string
@@ -141,23 +155,16 @@ end
 
 ---@param r ow.Git.Repo
 ---@param rev ow.Git.Revision
----@param content string?
 ---@return integer
-function M.buf_for(r, rev, content)
+function M.buf_for(r, rev)
     local buf = vim.fn.bufadd(M.format_uri(rev))
     repo.bind(buf, r)
-    if content and not vim.api.nvim_buf_is_loaded(buf) then
-        local state = r:state(buf) --[[@as -nil]]
-        state.pending_content = content
-    end
     vim.fn.bufload(buf)
     return buf
 end
 
 ---@param buf integer
----@param opts { force?: boolean }?
-function M.read_uri(buf, opts)
-    opts = opts or {}
+function M.read_uri(buf)
     local name = vim.api.nvim_buf_get_name(buf)
     local rev = M.parse_uri(name)
     if not rev then
@@ -176,27 +183,20 @@ function M.read_uri(buf, opts)
     vim.bo[buf].swapfile = false
     vim.bo[buf].bufhidden = "hide"
 
-    ---@type string?
-    local stdout = state.pending_content
-    state.pending_content = nil
-    if stdout == nil then
-        local rev_sha = r:rev_parse(rev_str, true)
-        if not rev_sha then
-            return
-        end
-        if
-            not opts.force
-            and (rev_sha == state.sha or vim.bo[buf].modified)
-        then
-            return
-        end
-        stdout = util.exec(
-            { "git", "cat-file", "-p", rev_str },
-            { cwd = r.worktree }
-        )
+    local rev_sha = r:rev_parse(rev_str, true)
+    if not rev_sha then
+        return
     end
 
-    if stdout and rev.path == nil then
+    local stdout = util.exec(
+        { "git", "cat-file", "-p", rev_str },
+        { cwd = r.worktree }
+    )
+    if not stdout then
+        return
+    end
+
+    if rev.path == nil then
         local commit_sha = r:rev_parse(rev_str .. "^{commit}", true)
         if commit_sha then
             local patch = util.exec({
@@ -216,12 +216,11 @@ function M.read_uri(buf, opts)
         end
     end
 
-    if stdout then
-        vim.bo[buf].modifiable = true
-        vim.api.nvim_buf_set_lines(buf, 0, -1, false, util.split_lines(stdout))
-    end
+    vim.bo[buf].modifiable = true
+    vim.api.nvim_buf_set_lines(buf, 0, -1, false, util.split_lines(stdout))
 
-    state.sha = r:rev_parse(rev_str, true)
+    state.sha = rev_sha
+    state.immutable = is_immutable_rev(rev)
 
     if rev.stage == 0 and rev.path then
         vim.bo[buf].buftype = "acwrite"
@@ -249,6 +248,24 @@ function M.read_uri(buf, opts)
     vim.api.nvim_exec_autocmds("BufReadPost", { buffer = buf })
 end
 
+---@param buf integer
+---@param r ow.Git.Repo
+local function refresh(buf, r)
+    local state = r:state(buf)
+    if not state or state.immutable or vim.bo[buf].modified then
+        return
+    end
+    local rev = M.parse_uri(vim.api.nvim_buf_get_name(buf))
+    if not rev then
+        return
+    end
+    local rev_sha = r:rev_parse(rev:format(), true)
+    if not rev_sha or rev_sha == state.sha then
+        return
+    end
+    M.read_uri(buf)
+end
+
 ---@param r ow.Git.Repo
 ---@param blob string?
 ---@param path string
@@ -314,15 +331,11 @@ function M.open(r, rev, opts)
             parsed.base = sha
         end
     end
-    local content = util.exec(
-        { "git", "cat-file", "-p", parsed:format() },
-        { cwd = r.worktree, silent = true }
-    )
-    if not content then
+    if not r:rev_parse(parsed:format(), true) then
         util.error("not a git object: %s", rev)
         return
     end
-    local buf = M.buf_for(r, parsed, content)
+    local buf = M.buf_for(r, parsed)
     util.place_buf(buf, opts and opts.split)
 end
 
@@ -384,6 +397,6 @@ function M.open_under_cursor()
     return false
 end
 
-repo.on_uri_refresh(M.URI_PREFIX, M.read_uri)
+repo.on_uri_refresh(M.URI_PREFIX, refresh)
 
 return M
diff --git a/lua/git/repo.lua b/lua/git/repo.lua
index 588142a..af3a396 100644
--- a/lua/git/repo.lua
+++ b/lua/git/repo.lua
@@ -16,10 +16,10 @@ end
 ---@field repo ow.Git.Repo
 ---@field sha string?
 ---@field parent_sha string?
+---@field immutable boolean?
 ---@field index_writer boolean?
 ---@field index_mode string?
 ---@field log_max_count integer?
----@field pending_content string?
 
 ---@alias ow.Git.Repo.Event "refresh"
 
@@ -208,7 +208,7 @@ function M.on(event, fn)
 end
 
 ---@param prefix string
----@param fn fun(buf: integer)
+---@param fn fun(buf: integer, r: ow.Git.Repo)
 ---@return fun() unsubscribe
 function M.on_uri_refresh(prefix, fn)
     return M.on("refresh", function(r)
@@ -216,7 +216,7 @@ function M.on_uri_refresh(prefix, fn)
             if vim.api.nvim_buf_is_valid(buf) then
                 local name = vim.api.nvim_buf_get_name(buf)
                 if name:sub(1, #prefix) == prefix then
-                    fn(buf)
+                    fn(buf, r)
                 end
             end
         end