diff --git a/.readthedocs.yml b/.readthedocs.yml
index af7d2d9..2ec5e0b 100644
--- a/.readthedocs.yml
+++ b/.readthedocs.yml
@@ -1,10 +1,14 @@
 version: 2
 
 build:
-  image: latest
+  os: ubuntu-22.04
+  tools:
+    python: mambaforge-4.10
+
+conda:
+  environment: .readthedocs_env.yml
 
 python:
-  version: 3.8
   install:
     - method: pip
       path: .
@@ -13,3 +17,6 @@ python:
 
 # Don't build any extra formats
 formats: []
+
+sphinx:
+  configuration: docs/source/conf.py
diff --git a/.readthedocs_env.yml b/.readthedocs_env.yml
new file mode 100644
index 0000000..07e7f26
--- /dev/null
+++ b/.readthedocs_env.yml
@@ -0,0 +1,20 @@
+name: pwkit_rtd
+channels:
+  - conda-forge
+
+dependencies:
+  - astropy
+  - mock
+  - numpydoc
+  - pandas
+  - pip
+  - python =3.12
+  - scipy
+  - setuptools
+  - sphinx
+  - sphinx_rtd_theme
+  # Work around an issue with v0.17 as seen in:
+  # https://github.com/WorldWideTelescope/pywwt/pull/375
+  # https://github.com/WorldWideTelescope/pywwt/commit/66480282c578353ea04d6716ca6015fec9370c44
+  # 0.18 is now available and may fix this.
+  - sphinx-automodapi=0.16
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 5b282ee..1f3c358 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,13 @@
+# pwkit 1.2.1 (2024-09-13)
+
+- Fix `pwkit.parallel.SerialHelper.get_map()` for Python 3 (#22)
+- Fix `pwkit.lmmin.Problem.set_npar()` for recent Numpys (#20). I'm not sure if
+  we'll be compatible with Numpy 2.0, though.
+- Get the ReadTheDocs docs building again, and make it so that we check RTD
+  builds as part of pull request processing
+- README.md: fix some links to the documentation (@AstroGenevieve)
+
+
 # pwkit 1.2.0 (2023-06-18)
 
 - Remove the dependency on `six`
diff --git a/README.md b/README.md
index e739acf..3278de2 100644
--- a/README.md
+++ b/README.md
@@ -9,8 +9,8 @@ This is a collection of Peter Williams’ miscellaneous Python tools.
 The online documentation contains [installation instructions]. The
 documentation is very much a work in progress but [may be found here].
 
-[installation instructions]: http://pwkit.readthedocs.org/en/latest/about/#installation
-[may be found here]: http://pwkit.readthedocs.org/en/latest/
+[installation instructions]: https://pwkit.readthedocs.io/en/latest/about.html#installation
+[may be found here]: https://pwkit.readthedocs.io/en/latest/
 
 
 ## Citation
@@ -47,7 +47,7 @@ include after your Acknowledgments section would be:
 
 See the [online documentation].
 
-[online documentation]: http://pwkit.readthedocs.org/en/latest/about/#authors
+[online documentation]: https://pwkit.readthedocs.io/en/latest/about.html#authors
 
 
 ## License
diff --git a/ci/azure-build-and-test.yml b/ci/azure-build-and-test.yml
index 54509a2..ae6baf5 100644
--- a/ci/azure-build-and-test.yml
+++ b/ci/azure-build-and-test.yml
@@ -6,12 +6,12 @@ parameters:
   default:
 
   - name: linux_310
-    vmImage: ubuntu-20.04
+    vmImage: ubuntu-latest
     vars:
       PYTHON_SERIES: "3.10"
 
   - name: macos_310
-    vmImage: macos-11
+    vmImage: macos-latest
     vars:
       PYTHON_SERIES: "3.10"
 
diff --git a/ci/zenodo.json5 b/ci/zenodo.json5
index 91a84ee..6e57180 100644
--- a/ci/zenodo.json5
+++ b/ci/zenodo.json5
@@ -30,13 +30,13 @@
     ],
     "language": "eng",
     "license": "MIT",
-    "publication_date": "2023-06-18",
-    "title": "pwkit 1.2.0",
+    "publication_date": "2024-09-13",
+    "title": "pwkit 1.2.1",
     "upload_type": "software",
-    "version": "1.2.0"
+    "version": "1.2.1"
   },
   "conceptdoi": "10.5281/zenodo.8052838",
-  "record_id": "8052937",
-  "doi": "10.5281/zenodo.8052937",
-  "bucket_link": "https://zenodo.org/api/files/355c89ba-b49c-4ead-a3bb-2f3055c53d01"
+  "record_id": "13759572",
+  "doi": "10.5281/zenodo.13759572",
+  "bucket_link": "https://zenodo.org/api/files/40de735d-83fa-49e5-916f-48ed93a74ad9"
 }
diff --git a/docs/source/conf.py b/docs/source/conf.py
index cb06baa..1bb944c 100644
--- a/docs/source/conf.py
+++ b/docs/source/conf.py
@@ -11,7 +11,7 @@
 ]
 
 project = "pwkit"
-release = "1.2.0"  # cranko project-version
+release = "1.2.1"  # cranko project-version
 version = ".".join(release.split(".")[:2])
 
 copyright = "2015-2023, Peter K. G. Williams and collaborators"
diff --git a/pwkit/__init__.py b/pwkit/__init__.py
index fff7474..650e65f 100644
--- a/pwkit/__init__.py
+++ b/pwkit/__init__.py
@@ -9,7 +9,7 @@
 
 __all__ = "Holder PKError binary_type reraise_context text_type unicode_to_str".split()
 
-__version__ = "1.2.0"  # cranko project-version
+__version__ = "1.2.1"  # cranko project-version
 
 # Archaic Python 2/3 compatibility support
 
diff --git a/pwkit/lmmin.py b/pwkit/lmmin.py
index ab8afaa..f2d3496 100644
--- a/pwkit/lmmin.py
+++ b/pwkit/lmmin.py
@@ -1328,7 +1328,7 @@ def set_npar(self, npar):
         p[PI_F_STEP] = 0.0
         p[PI_F_MAXSTEP] = np.inf
 
-        newinfoo = p = np.ndarray((PI_NUM_O, npar), dtype=np.object)
+        newinfoo = p = np.ndarray((PI_NUM_O, npar), dtype=object)
         p[PI_O_TIEFUNC] = None
 
         newinfob = p = np.ndarray(npar, dtype=int)
diff --git a/pwkit/parallel.py b/pwkit/parallel.py
index acb589e..8b5aa37 100644
--- a/pwkit/parallel.py
+++ b/pwkit/parallel.py
@@ -272,7 +272,7 @@ def __init__(self, chunksize=None):
         pass
 
     def get_map(self):
-        return VacuousContextManager(map)
+        return VacuousContextManager(lambda f, v: [f(x) for x in v])
 
     def get_ppmap(self):
         return VacuousContextManager(serial_ppmap)
diff --git a/setup.py b/setup.py
index 6300b43..187c333 100644
--- a/setup.py
+++ b/setup.py
@@ -37,7 +37,7 @@ def get_long_desc():
 
 setup(
     name="pwkit",  # cranko project-name
-    version="1.2.0",  # cranko project-version
+    version="1.2.1",  # cranko project-version
     # This package actually *is* zip-safe, but I've run into issues with
     # installing it as a Zip: in particular, the install sometimes fails with
     # "bad local file header", and reloading a module after a reinstall in