diff --git a/SphereEversion/Local/HPrinciple.lean b/SphereEversion/Local/HPrinciple.lean
index 990acf68..87ce6f5c 100644
--- a/SphereEversion/Local/HPrinciple.lean
+++ b/SphereEversion/Local/HPrinciple.lean
@@ -234,7 +234,7 @@ def improveStep {𝓕 : FormalSol R} (h : L.Accepts R 𝓕) (N : ℝ) : HtpyJetS
       · exact smoothStep.smooth.fst'.mul L.ρ_smooth.snd'
       · apply contDiff_const.mul L.π.contDiff.snd'
       · exact contDiff_snd
-    · apply ContDiff.smul
+    · apply ContDiff.fun_smul
       · exact smoothStep.smooth.fst'.mul L.ρ_smooth.snd'
       · exact Remainder.smooth _ _ (L.loop_smooth h) contDiff_snd contDiff_const
 
diff --git a/SphereEversion/ToMathlib/Analysis/ContDiff.lean b/SphereEversion/ToMathlib/Analysis/ContDiff.lean
index 40609931..0354b695 100644
--- a/SphereEversion/ToMathlib/Analysis/ContDiff.lean
+++ b/SphereEversion/ToMathlib/Analysis/ContDiff.lean
@@ -246,7 +246,7 @@ theorem contDiffAt_orthogonalProjection_singleton {v₀ : E} (hv₀ : v₀ ≠ 0
     refine this.congr_of_eventuallyEq ?_
     filter_upwards with v
     rw [orthogonalProjection_singleton', RCLike.ofReal_real_eq_id, _root_.id_def]
-  refine ContDiffAt.smul ?_ ?_
+  refine ContDiffAt.fun_smul ?_ ?_
   · exact contDiffAt_const.div (contDiff_norm_sq ℝ).contDiffAt
       (pow_ne_zero _ (norm_ne_zero_iff.mpr hv₀))
   · exact ((contDiff_toSpanSingleton ℝ E).clm_comp
diff --git a/lake-manifest.json b/lake-manifest.json
index 92d3cc0a..02b51660 100644
--- a/lake-manifest.json
+++ b/lake-manifest.json
@@ -15,7 +15,7 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "c1d772d6329adbf19893119c31cea6c4127420e7",
+   "rev": "a3a10db0e9d66acbebf76c5e6a135066525ac900",
    "name": "mathlib",
    "manifestFile": "lake-manifest.json",
    "inputRev": "master",
@@ -25,7 +25,7 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "b3dd6c3ebc0a71685e86bea9223be39ea4c299fb",
+   "rev": "009dc1e6f2feb2c96c081537d80a0905b2c6498f",
    "name": "plausible",
    "manifestFile": "lake-manifest.json",
    "inputRev": "main",
@@ -45,7 +45,7 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "cff9dd30f2c161b9efd7c657cafed1f967645890",
+   "rev": "8f497d55985a189cea8020d9dc51260af1e41ad2",
    "name": "importGraph",
    "manifestFile": "lake-manifest.json",
    "inputRev": "main",
@@ -55,17 +55,17 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "ef8377f31b5535430b6753a974d685b0019d0681",
+   "rev": "c04225ee7c0585effbd933662b3151f01b600e40",
    "name": "proofwidgets",
    "manifestFile": "lake-manifest.json",
-   "inputRev": "v0.0.84",
+   "inputRev": "v0.0.85",
    "inherited": true,
    "configFile": "lakefile.lean"},
   {"url": "https://github.com/leanprover-community/aesop",
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "fa78cf032194308a950a264ed87b422a2a7c1c6c",
+   "rev": "cb837cc26236ada03c81837bebe0acd9c70ced7d",
    "name": "aesop",
    "manifestFile": "lake-manifest.json",
    "inputRev": "master",
@@ -75,7 +75,7 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "8920dcbb96a4e8bf641fc399ac9c0888e4a6be72",
+   "rev": "bd58c9efe2086d56ca361807014141a860ddbf8c",
    "name": "Qq",
    "manifestFile": "lake-manifest.json",
    "inputRev": "master",
@@ -85,7 +85,7 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover-community",
-   "rev": "5ba0380f2fb45c69448d80429ef6c22bf5973cfa",
+   "rev": "b25b36a7caf8e237e7d1e6121543078a06777c8a",
    "name": "batteries",
    "manifestFile": "lake-manifest.json",
    "inputRev": "main",
@@ -95,10 +95,10 @@
    "type": "git",
    "subDir": null,
    "scope": "leanprover",
-   "rev": "726b98c53e2da249c1de768fbbbb5e67bc9cef60",
+   "rev": "55c37290ff6186e2e965d68cf853a57c0702db82",
    "name": "Cli",
    "manifestFile": "lake-manifest.json",
-   "inputRev": "v4.27.0-rc1",
+   "inputRev": "v4.27.0",
    "inherited": true,
    "configFile": "lakefile.toml"}],
  "name": "SphereEversion",
diff --git a/lean-toolchain b/lean-toolchain
index fb18a7f4..2bb276aa 100644
--- a/lean-toolchain
+++ b/lean-toolchain
@@ -1 +1 @@
-leanprover/lean4:v4.27.0-rc1
\ No newline at end of file
+leanprover/lean4:v4.27.0
\ No newline at end of file