diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index efc70c1..fa3a2c2 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -128,6 +128,29 @@ jobs:
         run: |
           nextflow run ${GITHUB_WORKSPACE} -profile test,docker --outdir ./results ${{ matrix.parameters }}
 
+  wfmash_sparse_map:
+    name: Run pipeline with wfmash_sparse_map parameters
+    # Only run on push if this is the nf-core dev branch (merged PRs)
+    if: "${{ github.event_name != 'push' || (github.event_name == 'push' && github.repository == 'nf-core/pangenome') }}"
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        parameters:
+          - "--wfmash_sparse_map auto"
+          - "--wfmash_sparse_map 0.5"
+    steps:
+      - name: Check out pipeline code
+        uses: actions/checkout@v3
+
+      - name: Install Nextflow
+        uses: nf-core/setup-nextflow@v1
+        with:
+          version: "23.04.0"
+
+      - name: Run pipeline with test data and wfmash_only parameters
+        run: |
+          nextflow run ${GITHUB_WORKSPACE} -profile test,docker --outdir ./results ${{ matrix.parameters }}
+
   communities:
     name: Run pipeline with community parameters
     # Only run on push if this is the nf-core dev branch (merged PRs)
diff --git a/conf/modules.config b/conf/modules.config
index f2846ae..9cb71e5 100644
--- a/conf/modules.config
+++ b/conf/modules.config
@@ -15,10 +15,10 @@ def generate_wfmash_sparse_map_cmd() {
     def wfmash_sparse_map_cmd = ""
     if (params.wfmash_sparse_map == "auto") {
         def n = params.n_haplotypes
-        def x = Math.log(n)/n * 10
-        wfmash_sparse_map_frac = 1
-        if (x < 1) {
-            def wfmash_sparse_map_frac = x
+        def x = Math.log(n)/n * 10.0
+        wfmash_sparse_map_frac = 1.0
+        if (x < 1.0) {
+            wfmash_sparse_map_frac = x
         }
         wfmash_sparse_map_cmd = "-x ${wfmash_sparse_map_frac}"
     } else {
diff --git a/nextflow.config b/nextflow.config
index a36f5e9..d6cd51c 100644
--- a/nextflow.config
+++ b/nextflow.config
@@ -101,7 +101,7 @@ params {
 
     // Schema validation default options
     validationFailUnrecognisedParams = false
-    validationLenientMode            = false
+    validationLenientMode            = true
     validationSchemaIgnoreParams     = 'genomes'
     validationShowHiddenParams       = false
     validate_params                  = true
diff --git a/nextflow_schema.json b/nextflow_schema.json
index 44f6c3f..ce320e9 100644
--- a/nextflow_schema.json
+++ b/nextflow_schema.json
@@ -54,7 +54,7 @@
             "properties": {
                 "wfmash_map_pct_id": {
                     "type": "number",
-                    "default": 90,
+                    "default": 90.0,
                     "description": "Percent identity in the wfmash mashmap step.",
                     "help_text": "Use `mash dist` or `mash triangle` to explore the typical level of divergence between the sequences in your input (see https://pggb.readthedocs.io/en/latest/rst/tutorials/divergence_estimation.html#divergence-estimation for more information). Convert this to an approximate percent identity and provide it as --wfmash_map_pct_id <PCT>. A list of examples can be found at https://github.com/pangenome/pggb#example-builds-for-diverse-species."
                 },
@@ -81,9 +81,10 @@
                     "description": "Ignore the top % most-frequent kmers."
                 },
                 "wfmash_sparse_map": {
-                    "type": "number",
-                    "default": "1.0",
-                    "description": "Keep this fraction of mappings (\"auto\" for giant component heuristic)."
+                    "default": 1.0,
+                    "description": "Keep this fraction of mappings (\"auto\" for giant component heuristic).",
+                    "type": "string",
+                    "pattern": "(auto|[01]\\.\\d+)"
                 },
                 "wfmash_merge_segments": {
                     "type": "boolean",
@@ -136,7 +137,7 @@
                 },
                 "seqwish_sparse_factor": {
                     "type": "number",
-                    "default": 0,
+                    "default": 0.0,
                     "description": "Keep this randomly selected fraction of input matches."
                 },
                 "seqwish_temp_dir": {
@@ -360,14 +361,12 @@
                     "type": "boolean",
                     "description": "Display help text.",
                     "fa_icon": "fas fa-question-circle",
-                    "default": false,
                     "hidden": true
                 },
                 "version": {
                     "type": "boolean",
                     "description": "Display version and exit.",
                     "fa_icon": "fas fa-question-circle",
-                    "default": false,
                     "hidden": true
                 },
                 "publish_dir_mode": {
@@ -391,7 +390,6 @@
                     "type": "boolean",
                     "description": "Send plain-text email instead of HTML.",
                     "fa_icon": "fas fa-remove-format",
-                    "default": false,
                     "hidden": true
                 },
                 "max_multiqc_email_size": {
@@ -406,7 +404,6 @@
                     "type": "boolean",
                     "description": "Do not use coloured log outputs.",
                     "fa_icon": "fas fa-palette",
-                    "default": false,
                     "hidden": true
                 },
                 "hook_url": {
@@ -445,7 +442,6 @@
                     "type": "boolean",
                     "fa_icon": "far fa-eye-slash",
                     "description": "Show all params when using `--help`",
-                    "default": false,
                     "hidden": true,
                     "help_text": "By default, parameters set as _hidden_ in the schema are not shown on the command line when a user runs with `--help`. Specifying this option will tell the pipeline to show all parameters."
                 },
@@ -453,7 +449,6 @@
                     "type": "boolean",
                     "fa_icon": "far fa-check-circle",
                     "description": "Validation of parameters fails when an unrecognised parameter is found.",
-                    "default": false,
                     "hidden": true,
                     "help_text": "By default, when an unrecognised parameter is found, it returns a warinig."
                 },
@@ -461,7 +456,6 @@
                     "type": "boolean",
                     "fa_icon": "far fa-check-circle",
                     "description": "Validation of parameters in lenient more.",
-                    "default": false,
                     "hidden": true,
                     "help_text": "Allows string values that are parseable as numbers or booleans. For further information see [JSONSchema docs](https://github.com/everit-org/json-schema#lenient-mode)."
                 },
@@ -469,7 +463,6 @@
                     "type": "boolean",
                     "fa_icon": "far fa-check-circle",
                     "description": "Do we want to display hidden parameters?",
-                    "default": false,
                     "hidden": true,
                     "help_text": "Do we want to display hidden parameters?"
                 },