diff --git a/package-lock.json b/package-lock.json
index 3687a7ea..f8234b61 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1214,8 +1214,9 @@
             "dev": true
         },
         "@exabyte-io/esse.js": {
-            "version": "git+https://github.com/Exabyte-io/esse.git#6f9515988dd2ae589bc74a6096cc743b5dba3225",
-            "from": "git+https://github.com/Exabyte-io/esse.git#update/SOF-6535",
+            "version": "2023.7.28-0",
+            "resolved": "https://registry.npmjs.org/@exabyte-io/esse.js/-/esse.js-2023.7.28-0.tgz",
+            "integrity": "sha512-B+0LF2GDKO3qb910lOvWS3YpusltJL5KdNqdjO//ljZ677fmH89VgMr82BM8jAhIEx5Uo6bZZ/Fwdsl+oYsUMg==",
             "requires": {
                 "@babel/cli": "7.16.0",
                 "@babel/core": "7.16.0",
diff --git a/src/utils/yaml.js b/src/utils/yaml.js
index eaa51e3f..1ea148cb 100644
--- a/src/utils/yaml.js
+++ b/src/utils/yaml.js
@@ -183,11 +183,62 @@ export const includeType = new yaml.Type("!include", {
     },
 });
 
+/**
+ * !flatten YAML tag for flattening arrays
+ * See the tests for example usage.
+ */
+export const flattenType = new yaml.Type("!flatten", {
+    kind: "sequence",
+    construct(data) {
+        try {
+            return data.flat();
+        } catch (e) {
+            return data;
+        }
+    },
+});
+
+/**
+ * !readFile YAML tag for including file contents as a string.
+ * See the tests for example usage.
+ */
+export const readFileType = new yaml.Type("!readFile", {
+    kind: "scalar",
+    construct(data) {
+        try {
+            return fs.readFileSync(path.resolve(data), "utf8");
+        } catch (e) {
+            return data;
+        }
+    },
+});
+
+/**
+ * !concatString YAML tag for concatenating strings.
+ * See the tests for example usage.
+ */
+export const concatStringType = new yaml.Type("!concatString", {
+    kind: "sequence",
+    resolve(data) {
+        return data.every((d) => lodash.isString(d));
+    },
+    construct(data) {
+        try {
+            return "".concat(...data);
+        } catch (e) {
+            return data;
+        }
+    },
+});
+
 export const JsYamlTypes = {
     include: includeType,
     parameter: parameterType,
     combine: combineType,
     esse: esseType,
+    flatten: flattenType,
+    readFile: readFileType,
+    concatString: concatStringType,
 };
 
 export const JsYamlAllSchemas = yaml.DEFAULT_SCHEMA.extend([
@@ -195,4 +246,7 @@ export const JsYamlAllSchemas = yaml.DEFAULT_SCHEMA.extend([
     combineType,
     esseType,
     includeType,
+    flattenType,
+    readFileType,
+    concatStringType,
 ]);
diff --git a/tests/enums.js b/tests/enums.js
index 83bc91ed..cb343f90 100644
--- a/tests/enums.js
+++ b/tests/enums.js
@@ -5,3 +5,6 @@ export const YAML_COMBINE_FILE = path.resolve(FIXTURES_DIR, "yaml_combine_tag.ym
 export const YAML_PARAMETER_FILE = path.resolve(FIXTURES_DIR, "yaml_parameter_tag.yml");
 export const YAML_ESSE_FILE = path.resolve(FIXTURES_DIR, "yaml_esse_tag.yml");
 export const YAML_INCLUDE_FILE = path.resolve(FIXTURES_DIR, "yaml_include_tag.yml");
+export const YAML_FLATTEN_FILE = path.resolve(FIXTURES_DIR, "yaml_flatten_tag.yml");
+export const YAML_READFILE_FILE = path.resolve(FIXTURES_DIR, "yaml_readFile_tag.yml");
+export const YAML_CONCAT_STRING_FILE = path.resolve(FIXTURES_DIR, "yaml_concatString_tag.yml");
diff --git a/tests/fixtures/test_content.txt b/tests/fixtures/test_content.txt
new file mode 100644
index 00000000..770b738d
--- /dev/null
+++ b/tests/fixtures/test_content.txt
@@ -0,0 +1,2 @@
+Example text
+with linebreaks.
diff --git a/tests/fixtures/yaml_concatString_tag.yml b/tests/fixtures/yaml_concatString_tag.yml
new file mode 100644
index 00000000..7189fbca
--- /dev/null
+++ b/tests/fixtures/yaml_concatString_tag.yml
@@ -0,0 +1,10 @@
+# concatenate three strings
+case1: !concatString
+    - "Hello "
+    - world
+    - "!"
+# return a string if there is only a single item
+case2: !concatString
+    - Hello
+# return an empty string if the array is empty
+case3: !concatString []
diff --git a/tests/fixtures/yaml_flatten_tag.yml b/tests/fixtures/yaml_flatten_tag.yml
new file mode 100644
index 00000000..21be0374
--- /dev/null
+++ b/tests/fixtures/yaml_flatten_tag.yml
@@ -0,0 +1,5 @@
+# convert an array of arrays into a flattened array
+case1: !flatten
+    - [a, b, c]
+    - d
+    - [e, f]
diff --git a/tests/fixtures/yaml_readFile_tag.yml b/tests/fixtures/yaml_readFile_tag.yml
new file mode 100644
index 00000000..db69653a
--- /dev/null
+++ b/tests/fixtures/yaml_readFile_tag.yml
@@ -0,0 +1,2 @@
+# read contents of a file into a string
+case1: !readFile "tests/fixtures/test_content.txt"
diff --git a/tests/utils/yaml.combine.tests.js b/tests/utils/yaml.combine.tests.js
index 04065f50..e4da8936 100644
--- a/tests/utils/yaml.combine.tests.js
+++ b/tests/utils/yaml.combine.tests.js
@@ -10,7 +10,12 @@ import { YAML_COMBINE_FILE } from "../enums";
 const combineSchema = yaml.DEFAULT_SCHEMA.extend([combineType, esseType]);
 
 describe("YAML tag: !combine", () => {
-    const yamlFixture = fs.readFileSync(YAML_COMBINE_FILE, "utf8");
+    let yamlFixture;
+
+    before(() => {
+        yamlFixture = fs.readFileSync(YAML_COMBINE_FILE, "utf8");
+    });
+
     it("should correctly parse a custom !combine tag with forEach and config keys", () => {
         const parsed = yaml.load(yamlFixture, { schema: combineSchema });
         const expectedResult = [
diff --git a/tests/utils/yaml.concatString.tests.js b/tests/utils/yaml.concatString.tests.js
new file mode 100644
index 00000000..df7201c4
--- /dev/null
+++ b/tests/utils/yaml.concatString.tests.js
@@ -0,0 +1,30 @@
+import { expect } from "chai";
+import fs from "fs";
+import yaml from "js-yaml";
+
+import { concatStringType } from "../../src/utils/yaml";
+import { YAML_CONCAT_STRING_FILE } from "../enums";
+
+const concatStringSchema = yaml.DEFAULT_SCHEMA.extend([concatStringType]);
+
+describe("YAML tag: !concatString", () => {
+    const yamlFixture = fs.readFileSync(YAML_CONCAT_STRING_FILE, "utf8");
+
+    it("should concatenate two strings", () => {
+        const parsed = yaml.load(yamlFixture, { schema: concatStringSchema });
+        const expected = "Hello world!";
+        expect(parsed.case1).to.be.eql(expected);
+    });
+
+    it("should return a string if there is only a single item", () => {
+        const parsed = yaml.load(yamlFixture, { schema: concatStringSchema });
+        const expected = "Hello";
+        expect(parsed.case2).to.be.eql(expected);
+    });
+
+    it("should return an empty string if the array is empty", () => {
+        const parsed = yaml.load(yamlFixture, { schema: concatStringSchema });
+        const expected = "";
+        expect(parsed.case3).to.be.eql(expected);
+    });
+});
diff --git a/tests/utils/yaml.flatten.tests.js b/tests/utils/yaml.flatten.tests.js
new file mode 100644
index 00000000..01bb851b
--- /dev/null
+++ b/tests/utils/yaml.flatten.tests.js
@@ -0,0 +1,18 @@
+import { expect } from "chai";
+import fs from "fs";
+import yaml from "js-yaml";
+
+import { flattenType } from "../../src/utils/yaml";
+import { YAML_FLATTEN_FILE } from "../enums";
+
+const flattenSchema = yaml.DEFAULT_SCHEMA.extend([flattenType]);
+
+describe("YAML tag: !flatten", () => {
+    const yamlFixture = fs.readFileSync(YAML_FLATTEN_FILE, "utf8");
+
+    it("should convert an array of arrays into a flattened array", () => {
+        const parsed = yaml.load(yamlFixture, { schema: flattenSchema });
+        const expected = ["a", "b", "c", "d", "e", "f"];
+        expect(parsed.case1).to.be.eql(expected);
+    });
+});
diff --git a/tests/utils/yaml.readFile.tests.js b/tests/utils/yaml.readFile.tests.js
new file mode 100644
index 00000000..0d6ed074
--- /dev/null
+++ b/tests/utils/yaml.readFile.tests.js
@@ -0,0 +1,19 @@
+import { expect } from "chai";
+import fs from "fs";
+import yaml from "js-yaml";
+
+import { readFileType } from "../../src/utils/yaml";
+import { YAML_READFILE_FILE } from "../enums";
+
+const readFileSchema = yaml.DEFAULT_SCHEMA.extend([readFileType]);
+
+describe("YAML tag: !readFile", () => {
+    const yamlFixture = fs.readFileSync(YAML_READFILE_FILE, "utf8");
+
+    it("should read contents of a file into a string", () => {
+        const parsed = yaml.load(yamlFixture, { schema: readFileSchema });
+        const expected = "Example text\nwith linebreaks.\n";
+        expect(parsed.case1).to.be.a("string");
+        expect(parsed.case1).to.be.eql(expected);
+    });
+});