diff --git a/joj3_config_generator/models/repo.py b/joj3_config_generator/models/repo.py
index 20cf756..eeb99be 100644
--- a/joj3_config_generator/models/repo.py
+++ b/joj3_config_generator/models/repo.py
@@ -1,8 +1,10 @@
 import os
 from pathlib import Path
-from typing import List
+from typing import Any, List
 
-from pydantic import AliasChoices, BaseModel, Field, model_validator
+from pydantic import AliasChoices, BaseModel, Field, field_validator, model_validator
+
+from joj3_config_generator.models.common import Memory
 
 
 class Files(BaseModel):
@@ -34,6 +36,24 @@ class Issue(BaseModel):
     )
 
 
+class HealthCheck(BaseModel):
+    score: int = 0
+    max_size: int = Field(
+        Memory("10m"), validation_alias=AliasChoices("max-size", "max_size")
+    )
+    immutable_path: Path = Field(
+        Path("immutable"),
+        validation_alias=AliasChoices("immutable-path", "immutable_path"),
+    )
+
+    @field_validator("max_size", mode="before")
+    @classmethod
+    def ensure_mem_type(cls, v: Any) -> Memory:
+        if isinstance(v, str):
+            return Memory(v)
+        raise ValueError(f'Must be a string, e.g., "256m" or "1g", but got {v}')
+
+
 class Config(BaseModel):
     root: Path = Field(Path("."), exclude=True)
     path: Path = Field(Path("repo.toml"), exclude=True)
@@ -52,9 +72,9 @@ class Config(BaseModel):
         ),
         exclude=True,
     )
-
-    max_size: float = Field(
-        10, ge=0, validation_alias=AliasChoices("max-size", "max_size")
+    grading_repo_name: str = Field(
+        "",
+        validation_alias=AliasChoices("grading-repo-name", "grading_repo_name"),
     )
     files: Files = Files()
     sandbox_token: str = Field(
@@ -64,18 +84,23 @@ class Config(BaseModel):
         100, validation_alias=AliasChoices("max-total-score", "max_total_score")
     )
     groups: Groups = Groups()
+    issue: Issue = Issue()
+
+    health_check: HealthCheck = Field(
+        HealthCheck(), validation_alias=AliasChoices("health-check", "health_check")
+    )
+    # TODO: remove max_size, health_check_score, and immutable_path in the future
+    max_size: float = Field(
+        10, ge=0, validation_alias=AliasChoices("max-size", "max_size")
+    )
     health_check_score: int = Field(
         0, validation_alias=AliasChoices("health-check-score", "health_check_score")
     )
-    issue: Issue = Issue()
     immutable_path: Path = Field(
         Path("immutable"),
         validation_alias=AliasChoices("immutable-path", "immutable_path"),
     )
-    grading_repo_name: str = Field(
-        "",
-        validation_alias=AliasChoices("grading-repo-name", "grading_repo_name"),
-    )
+
     # TODO: remove gitea_token and gitea_org in the future
     gitea_token: str = Field(
         "", validation_alias=AliasChoices("gitea-token", "gitea_token")
@@ -91,3 +116,14 @@ class Config(BaseModel):
             else:
                 self.grading_repo_name = Path.cwd().name
         return self
+
+    # TODO: remove this validator in the future
+    @model_validator(mode="after")
+    def set_health_check(self) -> "Config":
+        if "health_check_score" in self.model_fields_set:
+            self.health_check.score = self.health_check_score
+        if "max_size" in self.model_fields_set:
+            self.health_check.max_size = Memory(f"{self.max_size}m")
+        if "immutable_path" in self.model_fields_set:
+            self.health_check.immutable_path = self.immutable_path
+        return self
diff --git a/joj3_config_generator/transformers/repo.py b/joj3_config_generator/transformers/repo.py
index 18e254a..4765a3e 100644
--- a/joj3_config_generator/transformers/repo.py
+++ b/joj3_config_generator/transformers/repo.py
@@ -101,7 +101,9 @@ def get_check_lists(repo_conf: repo.Config) -> Tuple[List[str], List[str]]:
         immutable_files.append(file_path)
         file_sums.append(calc_sha256sum(file_path))
         file_names.append(file)
-    immutable_dir = (repo_conf.root / repo_conf.path).parent / repo_conf.immutable_path
+    immutable_dir = (
+        repo_conf.root / repo_conf.path
+    ).parent / repo_conf.health_check.immutable_path
     if not immutable_dir.exists():
         return file_sums, file_names
     file_sums = []
@@ -122,7 +124,7 @@ def get_health_check_args(repo_conf: repo.Config) -> List[str]:
     return [
         "/usr/local/bin/repo-health-checker",
         "-root=.",
-        f"-repoSize={str(repo_conf.max_size)}",
+        f"-repoSize={str(repo_conf.health_check.max_size / 1024 / 1024)}",  # B -> MB
         *[f"-meta={meta}" for meta in repo_conf.files.required],
         f"-checkFileSumList={','.join(file_sums)}",
         f"-checkFileNameList={','.join(file_names)}",
@@ -194,7 +196,7 @@ def get_health_check_stage(
         parsers=[
             result.Parser(
                 name="healthcheck",
-                with_=result.ScoreConfig(score=repo_conf.health_check_score),
+                with_=result.ScoreConfig(score=repo_conf.health_check.score),
             ),
             result.Parser(name="debug"),
         ],
diff --git a/tests/convert/basic/repo.toml b/tests/convert/basic/repo.toml
index cf8d457..616456b 100644
--- a/tests/convert/basic/repo.toml
+++ b/tests/convert/basic/repo.toml
@@ -3,9 +3,9 @@ grading-repo-name = "ece280-joj"
 sandbox-token = "test"
 # reconfigure later
 max-total-score = 1000
-max-size = 50.5
 
-immutable_path = "immutable"
+health-check.max-size = "50.5m"
+health-check.immutable_path = "immutable"
 
 # for tests
 [groups]
diff --git a/tests/convert/full/repo.toml b/tests/convert/full/repo.toml
new file mode 100644
index 0000000..bbbf21c
--- /dev/null
+++ b/tests/convert/full/repo.toml
@@ -0,0 +1,23 @@
+files.required = ["README.md", "Changelog.md"] # required files name, case insensitive
+sandbox-token = "" # sandbox token
+
+health-check.score = 0 # score for health check stage
+health-check.max-size = "10m" # max size of the repository
+health-check.immutable-path = "immutable" # path for immutable files, relative to the path of repo.toml
+
+issue.label.name = "Kind/Testing" # label for issues
+issue.label.color = "#795548" # color for the label
+issue.label.exclusive = false # whether the label is exclusive
+issue.show-submitter = true # whether to show submitter in the issue title
+
+
+# fields below can be overridden by task.toml
+max-total-score = 100 # maximum total score for the task
+# submission count limit groups
+# explanation of the following config:
+# in last 1 hour, total submission <= 50 times
+# in last 24 hours, submission includes group "joj" <= 1000 times
+# in last 2 hours, submission includes group "run" <= 100 times
+groups.name = ["", "joj", "run"] # names of the groups
+groups.max-count = [50, 1000, 100] # maximum submission count for each group
+groups.time-period-hour = [1, 24, 2] # time period in hour for each group