diff --git a/src/assets/funcs.js b/src/assets/funcs.js
index ee8f12edb..1c4d6c802 100644
--- a/src/assets/funcs.js
+++ b/src/assets/funcs.js
@@ -87,6 +87,11 @@ export function renderGraph(canvas, dataset, labels, xAxis, alpha = 60, labelStr
                             lines.push(`  ${key}: ${value}`)
                         }
                     }
+                    if (data.extra) {
+                        for (const [key, value] of Object.entries(data.extra)) {
+                            lines.push(`${key}: ${value}`)
+                        }
+                    }
                     return '\n' + lines.join('\n') + '\n';
                 },
                 label: item => {
diff --git a/src/extract.ts b/src/extract.ts
index 6b042983f..de84b6c6a 100644
--- a/src/extract.ts
+++ b/src/extract.ts
@@ -33,6 +33,7 @@ export interface Benchmark {
     date: number;
     benches: BenchmarkResult[];
     cpu?: CpuData;
+    extra?: { [key: string]: string };
 }
 
 export interface PytestBenchmarkJson {
@@ -145,20 +146,23 @@ function getCommit(): Commit {
     /* eslint-enable @typescript-eslint/camelcase */
 }
 
-function extractPytestResult(output: string): BenchmarkResult[] {
+function extractPytestResult(output: string): { results: BenchmarkResult[]; extra: { [key: string]: string } } {
     try {
         const json: PytestBenchmarkJson = JSON.parse(output);
-        return json.benchmarks.map(bench => {
-            const stats = bench.stats;
-            const name = bench.fullname;
-            const group = bench.group;
-            const value = stats.ops;
-            const unit = 'iter/sec';
-            const range = `stddev: ${precise(stats.stddev)}`;
-            const [mean, meanUnit] = getHumanReadableUnitValue(stats.mean);
-            const extra = `mean: ${precise(mean)} ${meanUnit}\nrounds: ${stats.rounds}`;
-            return { name, value, unit, range, group, extra };
-        });
+        return {
+            extra: { pythonVersion: json.machine_info.python_version },
+            results: json.benchmarks.map(bench => {
+                const stats = bench.stats;
+                const name = bench.fullname;
+                const group = bench.group;
+                const value = stats.ops;
+                const unit = 'iter/sec';
+                const range = `stddev: ${precise(stats.stddev)}`;
+                const [mean, meanUnit] = getHumanReadableUnitValue(stats.mean);
+                const extra = `mean: ${precise(mean)} ${meanUnit}\nrounds: ${stats.rounds}`;
+                return { name, value, unit, range, group, extra };
+            }),
+        };
     } catch (err) {
         throw new Error(
             `Output file for 'pytest' must be JSON file generated by --benchmark-json option: ${err.message}`,
@@ -171,7 +175,7 @@ export async function extractResult(config: Config): Promise<Benchmark> {
 
     const benches = extractPytestResult(output);
 
-    if (benches.length === 0) {
+    if (benches.results.length === 0) {
         throw new Error(`No benchmark result was found in ${config.outputFilePath}. Benchmark output was '${output}'`);
     }
 
@@ -181,8 +185,9 @@ export async function extractResult(config: Config): Promise<Benchmark> {
 
     return {
         cpu: { speed, cores, physicalCores, processors },
+        extra: benches.extra,
         commit,
         date: Date.now(),
-        benches,
+        benches: benches.results,
     };
 }
diff --git a/test/assets.ts b/test/assets.ts
index 789589cf7..3c394673c 100644
--- a/test/assets.ts
+++ b/test/assets.ts
@@ -13,9 +13,13 @@ describe('check assets', function() {
         A.ok(s, 'main script');
     });
     it('main.js is valid Javascript', async function() {
-        // Verify HTML syntax
         const js = await fs.readFile(join(__dirname, '../src/assets/main.js'), 'utf8');
         // Verify JavaScript syntax. It raises an error if invalid
         JsParser.parse(js, { sourceType: 'module' });
     });
+    it('funcs.js is valid Javascript', async function() {
+        const js = await fs.readFile(join(__dirname, '../src/assets/funcs.js'), 'utf8');
+        // Verify JavaScript syntax. It raises an error if invalid
+        JsParser.parse(js, { sourceType: 'module' });
+    });
 });