diff --git a/com.io7m.adoptopenjdk.api/src/main/java/com/io7m/adoptopenjdk/api/AdoptOpenJDK.java b/com.io7m.adoptopenjdk.api/src/main/java/com/io7m/adoptopenjdk/api/AdoptOpenJDK.java
index 4984725..d07a04e 100644
--- a/com.io7m.adoptopenjdk.api/src/main/java/com/io7m/adoptopenjdk/api/AdoptOpenJDK.java
+++ b/com.io7m.adoptopenjdk.api/src/main/java/com/io7m/adoptopenjdk/api/AdoptOpenJDK.java
@@ -20,6 +20,7 @@
 import com.io7m.adoptopenjdk.spi.AOAPIVersionProviderType;
 import com.io7m.adoptopenjdk.spi.AOException;
 import com.io7m.adoptopenjdk.spi.AORelease;
+import com.io7m.adoptopenjdk.spi.AOVariant;
 
 import java.util.List;
 import java.util.Objects;
@@ -98,6 +99,13 @@ public int rateLimitRemaining()
       return this.requests.rateLimitRemaining();
     }
 
+    @Override
+    public List<AOVariant> variants()
+      throws AOException
+    {
+      return this.requests.variants();
+    }
+
     @Override
     public List<AORelease> releasesForVariant(final String variant)
       throws AOException
diff --git a/com.io7m.adoptopenjdk.spi/src/main/java/com/io7m/adoptopenjdk/spi/AOAPIRequestsType.java b/com.io7m.adoptopenjdk.spi/src/main/java/com/io7m/adoptopenjdk/spi/AOAPIRequestsType.java
index 98c6e93..bd88dd3 100644
--- a/com.io7m.adoptopenjdk.spi/src/main/java/com/io7m/adoptopenjdk/spi/AOAPIRequestsType.java
+++ b/com.io7m.adoptopenjdk.spi/src/main/java/com/io7m/adoptopenjdk/spi/AOAPIRequestsType.java
@@ -31,6 +31,17 @@ public interface AOAPIRequestsType
 
   int rateLimitRemaining();
 
+  /**
+   * List the available build variants on the server.
+   *
+   * @return A list of variants
+   *
+   * @throws AOException On any and all errors
+   */
+
+  List<AOVariant> variants()
+    throws AOException;
+
   /**
    * List the available releases on the server.
    *
diff --git a/com.io7m.adoptopenjdk.spi/src/main/java/com/io7m/adoptopenjdk/spi/AOVariantType.java b/com.io7m.adoptopenjdk.spi/src/main/java/com/io7m/adoptopenjdk/spi/AOVariantType.java
new file mode 100644
index 0000000..9d14d14
--- /dev/null
+++ b/com.io7m.adoptopenjdk.spi/src/main/java/com/io7m/adoptopenjdk/spi/AOVariantType.java
@@ -0,0 +1,42 @@
+/*
+ * Copyright © 2018 Mark Raynsford <code@io7m.com> http://io7m.com
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
+ * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR
+ * IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+package com.io7m.adoptopenjdk.spi;
+
+import org.immutables.value.Value;
+
+/**
+ * A build variant (such as {@code "openjdk8"}).
+ */
+
+@ImmutableStyleType
+@Value.Immutable
+public interface AOVariantType
+{
+  /**
+   * @return A variant identifier such as {@code "openjdk8"}.
+   */
+
+  @Value.Parameter
+  String name();
+
+  /**
+   * @return A humanly-readable description of the variant (such as {@code "OpenJDK 8 with Hotspot"})
+   */
+
+  @Value.Parameter
+  String description();
+}
diff --git a/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOV1RequestsIntegrationTest.java b/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOV1RequestsIntegrationTest.java
index dd1d1ea..ace9abd 100644
--- a/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOV1RequestsIntegrationTest.java
+++ b/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOV1RequestsIntegrationTest.java
@@ -18,6 +18,7 @@
 
 import com.io7m.adoptopenjdk.spi.AOException;
 import com.io7m.adoptopenjdk.spi.AORelease;
+import com.io7m.adoptopenjdk.spi.AOVariant;
 import com.io7m.adoptopenjdk.v1.AOv1HTTPException;
 import com.io7m.adoptopenjdk.v1.AOv1Requests;
 import com.io7m.adoptopenjdk.v1.AOv1RequestsType;
@@ -60,4 +61,22 @@ public void testParseOpenJDK8Releases()
       }
     }
   }
+
+  @Test
+  public void testParseVariants()
+    throws AOException
+  {
+    try {
+      final AOv1RequestsType requests = AOv1Requests.open();
+      final List<AOVariant> variants = requests.variants();
+      Assert.assertTrue(
+        "Must have at least one variant parsed",
+        variants.size() > 0);
+    } catch (final AOv1HTTPException e) {
+      if (e.statusCode() == 429) {
+        LOG.info("exceeded rate limit on server: ", e);
+        return;
+      }
+    }
+  }
 }
diff --git a/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOV1RequestsTest.java b/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOV1RequestsTest.java
index dcdf785..5017743 100644
--- a/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOV1RequestsTest.java
+++ b/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOV1RequestsTest.java
@@ -18,6 +18,7 @@
 
 import com.io7m.adoptopenjdk.spi.AOException;
 import com.io7m.adoptopenjdk.spi.AORelease;
+import com.io7m.adoptopenjdk.spi.AOVariant;
 import com.io7m.adoptopenjdk.tests.spi.AOReleasesTest;
 import com.io7m.adoptopenjdk.v1.AOv1Requests;
 import com.io7m.adoptopenjdk.v1.AOv1RequestsType;
@@ -132,4 +133,47 @@ public void testParseOpenJDK8ReleasesFiltered()
 
     Assert.assertEquals(releases_0, releases_1);
   }
+
+  @Test
+  public void testParseVariants()
+    throws AOException, IOException
+  {
+    final MockConnection connection_0 =
+      MockConnection.create(
+        Map.of("X-RateLimit-Remaining", "100",
+               "Retry-After", "3600"));
+
+    final MockConnection connection_1 =
+      MockConnection.createWithData(
+        Map.of("X-RateLimit-Remaining", "200",
+               "Retry-After", "3600"),
+        resource("variants.json"));
+
+    final MockConnections connections = new MockConnections();
+    connections.addConnection(connection_0);
+    connections.addConnection(connection_1);
+
+    final AOv1RequestsType requests = AOv1Requests.open(connections);
+    final List<AOVariant> variants = requests.variants();
+
+    Assert.assertEquals(200L, (long) requests.rateLimitRemaining());
+    Assert.assertEquals(0L, (long) connections.queue().size());
+    Assert.assertEquals(5L, (long) variants.size());
+
+    Assert.assertEquals(
+      AOVariant.of("openjdk8", "OpenJDK 8 with Hotspot"),
+      variants.get(0));
+    Assert.assertEquals(
+      AOVariant.of("openjdk8-openj9", "OpenJDK 8 with Eclipse OpenJ9"),
+      variants.get(1));
+    Assert.assertEquals(
+      AOVariant.of("openjdk9", "OpenJDK 9 with Hotspot"),
+      variants.get(2));
+    Assert.assertEquals(
+      AOVariant.of("openjdk9-openj9", "OpenJDK 9 with Eclipse OpenJ9"),
+      variants.get(3));
+    Assert.assertEquals(
+      AOVariant.of("openjdk10", "OpenJDK 10 with Hotspot"),
+      variants.get(4));
+  }
 }
diff --git a/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOv1ParserTest.java b/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOv1ParserTest.java
index 51fd069..f0e04bf 100644
--- a/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOv1ParserTest.java
+++ b/com.io7m.adoptopenjdk.tests/src/test/java/com/io7m/adoptopenjdk/tests/v1/AOv1ParserTest.java
@@ -18,6 +18,7 @@
 
 import com.io7m.adoptopenjdk.spi.AOParseException;
 import com.io7m.adoptopenjdk.spi.AORelease;
+import com.io7m.adoptopenjdk.spi.AOVariant;
 import com.io7m.adoptopenjdk.tests.spi.AOReleasesTest;
 import com.io7m.adoptopenjdk.v1.AOv1Parser;
 import org.junit.Assert;
@@ -155,4 +156,58 @@ public void testOpenJDK8Releases_Bad5()
       parser.parseReleases(URI.create("openjdk8.json"), stream);
     }
   }
+
+  @Test
+  public void testVariants()
+    throws Exception
+  {
+    final AOv1Parser parser = new AOv1Parser();
+
+    try (InputStream stream = resource("variants.json")) {
+      final List<AOVariant> variants =
+        parser.parseVariants(URI.create("variants.json"), stream);
+
+      Assert.assertEquals(5L, (long) variants.size());
+
+      Assert.assertEquals(
+        AOVariant.of("openjdk8", "OpenJDK 8 with Hotspot"),
+        variants.get(0));
+      Assert.assertEquals(
+        AOVariant.of("openjdk8-openj9", "OpenJDK 8 with Eclipse OpenJ9"),
+        variants.get(1));
+      Assert.assertEquals(
+        AOVariant.of("openjdk9", "OpenJDK 9 with Hotspot"),
+        variants.get(2));
+      Assert.assertEquals(
+        AOVariant.of("openjdk9-openj9", "OpenJDK 9 with Eclipse OpenJ9"),
+        variants.get(3));
+      Assert.assertEquals(
+        AOVariant.of("openjdk10", "OpenJDK 10 with Hotspot"),
+        variants.get(4));
+    }
+  }
+
+  @Test
+  public void testVariants_Bad0()
+    throws Exception
+  {
+    final AOv1Parser parser = new AOv1Parser();
+
+    try (InputStream stream = resource("variants_bad_0.json")) {
+      this.expected.expect(AOParseException.class);
+      parser.parseVariants(URI.create("variants_bad_0.json"), stream);
+    }
+  }
+
+  @Test
+  public void testVariants_Bad1()
+    throws Exception
+  {
+    final AOv1Parser parser = new AOv1Parser();
+
+    try (InputStream stream = resource("variants_bad_1.json")) {
+      this.expected.expect(AOParseException.class);
+      parser.parseVariants(URI.create("variants_bad_1.json"), stream);
+    }
+  }
 }
diff --git a/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants.json b/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants.json
new file mode 100644
index 0000000..7749931
--- /dev/null
+++ b/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants.json
@@ -0,0 +1,22 @@
+[
+  {
+    "name": "OpenJDK 8 with Hotspot",
+    "variant": "openjdk8"
+  },
+  {
+    "name": "OpenJDK 8 with Eclipse OpenJ9",
+    "variant": "openjdk8-openj9"
+  },
+  {
+    "name": "OpenJDK 9 with Hotspot",
+    "variant": "openjdk9"
+  },
+  {
+    "name": "OpenJDK 9 with Eclipse OpenJ9",
+    "variant": "openjdk9-openj9"
+  },
+  {
+    "name": "OpenJDK 10 with Hotspot",
+    "variant": "openjdk10"
+  }
+]
\ No newline at end of file
diff --git a/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants_bad_0.json b/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants_bad_0.json
new file mode 100644
index 0000000..6431a47
--- /dev/null
+++ b/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants_bad_0.json
@@ -0,0 +1,8 @@
+[
+  {
+    "name": "OpenJDK 8 with Hotspot"
+  },
+  {
+    "variant": "openjdk8-openj9"
+  }
+]
\ No newline at end of file
diff --git a/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants_bad_1.json b/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants_bad_1.json
new file mode 100644
index 0000000..8e2f0be
--- /dev/null
+++ b/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants_bad_1.json
@@ -0,0 +1 @@
+[
\ No newline at end of file
diff --git a/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants_warnings.json b/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants_warnings.json
new file mode 100644
index 0000000..9c9d6e7
--- /dev/null
+++ b/com.io7m.adoptopenjdk.tests/src/test/resources/com/io7m/adoptopenjdk/tests/v1/variants_warnings.json
@@ -0,0 +1,29 @@
+[
+  {
+    "name": "OpenJDK 8 with Hotspot",
+    "extra": "ignore me",
+    "variant": "openjdk8"
+  },
+  {
+    "name": "OpenJDK 8 with Eclipse OpenJ9",
+    "variant": "openjdk8-openj9",
+    "extra": {
+
+    }
+  },
+  {
+    "extra": [
+      "123"
+    ],
+    "name": "OpenJDK 9 with Hotspot",
+    "variant": "openjdk9"
+  },
+  {
+    "name": "OpenJDK 9 with Eclipse OpenJ9",
+    "variant": "openjdk9-openj9"
+  },
+  {
+    "name": "OpenJDK 10 with Hotspot",
+    "variant": "openjdk10"
+  }
+]
\ No newline at end of file
diff --git a/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1Parser.java b/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1Parser.java
index 9d92782..b0e106e 100644
--- a/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1Parser.java
+++ b/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1Parser.java
@@ -24,6 +24,7 @@
 import com.io7m.adoptopenjdk.spi.AOBinary;
 import com.io7m.adoptopenjdk.spi.AOParseException;
 import com.io7m.adoptopenjdk.spi.AORelease;
+import com.io7m.adoptopenjdk.spi.AOVariant;
 import com.io7m.jaffirm.core.Preconditions;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -498,4 +499,132 @@ private AOParseException parseErrorExpectedReceived(
     return this.parseErrorExpectedReceived(
       Optional.empty(), uri, parser, expected, received);
   }
+
+
+  /**
+   * Parse an array of variants.
+   *
+   * @param uri    The URI of the stream for diagnostic messages
+   * @param stream The input stream
+   *
+   * @return A list of releases
+   *
+   * @throws IOException      On I/O errors
+   * @throws AOParseException On parse errors
+   */
+
+  public List<AOVariant> parseVariants(
+    final URI uri,
+    final InputStream stream)
+    throws AOParseException, IOException
+  {
+    Objects.requireNonNull(uri, "uri");
+    Objects.requireNonNull(stream, "stream");
+
+    final Instant time_then = Instant.now();
+
+    try {
+      final List<AOVariant> variants = new ArrayList<>(8);
+      final JsonFactory parsers = new JsonFactory();
+      try (JsonParser parser = parsers.createParser(stream)) {
+        while (true) {
+          final JsonToken next = parser.nextToken();
+          LOG.trace("{}: token: {}", uri, next);
+          if (next == null) {
+            break;
+          }
+
+          this.requireOneOf(uri, parser, next, START_ARRAY);
+          this.parseVariantsArray(uri, parser, variants);
+        }
+      }
+
+      return variants;
+    } catch (final JsonProcessingException e) {
+      throw new AOParseException(e.getMessage(), e);
+    } finally {
+      final Instant time_now = Instant.now();
+      LOG.debug("parsed in {}", Duration.between(time_then, time_now));
+    }
+  }
+
+  /**
+   * Parse an array of variants from the given parser.
+   */
+
+  private void parseVariantsArray(
+    final URI uri,
+    final JsonParser parser,
+    final Collection<AOVariant> variants)
+    throws IOException, AOParseException
+  {
+    Preconditions.checkPrecondition(
+      parser.currentToken() == START_ARRAY,
+      "Parser must be at array start");
+
+    while (true) {
+      final JsonToken next = parser.nextToken();
+      LOG.trace("{}: token: {}", uri, next);
+      this.requireNotEOF(uri, parser, next);
+
+      this.requireOneOf(uri, parser, next, START_OBJECT, END_ARRAY);
+      if (next == END_ARRAY) {
+        return;
+      }
+
+      variants.add(this.parseVariant(uri, parser));
+    }
+  }
+
+  /**
+   * Parse a single variant from the given parser.
+   */
+
+  private AOVariant parseVariant(
+    final URI uri,
+    final JsonParser parser)
+    throws IOException, AOParseException
+  {
+    Preconditions.checkPrecondition(
+      parser.currentToken() == START_OBJECT,
+      "Parser must be at object start");
+
+    final AOVariant.Builder builder = AOVariant.builder();
+
+    while (true) {
+      final JsonToken next = parser.nextToken();
+      LOG.trace("{}: token: {}", uri, next);
+      this.requireNotEOF(uri, parser, next);
+
+      this.requireOneOf(uri, parser, next, FIELD_NAME, END_OBJECT);
+      if (next == END_OBJECT) {
+        break;
+      }
+
+      final String field_name = parser.getText();
+      switch (field_name) {
+        case "name": {
+          parser.nextToken();
+          builder.setDescription(parser.getText());
+          break;
+        }
+        case "variant": {
+          parser.nextToken();
+          builder.setName(parser.getText());
+          break;
+        }
+        default: {
+          LOG.warn("ignoring unrecognized field: {}", field_name);
+          parser.nextToken();
+          parser.skipChildren();
+        }
+      }
+    }
+
+    try {
+      return builder.build();
+    } catch (final IllegalStateException e) {
+      throw this.parseErrorMissingFields(uri, parser, e);
+    }
+  }
 }
diff --git a/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1Requests.java b/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1Requests.java
index 467c95b..9e01a24 100644
--- a/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1Requests.java
+++ b/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1Requests.java
@@ -20,6 +20,7 @@
 import com.io7m.adoptopenjdk.spi.AOAPIVersionProviderType;
 import com.io7m.adoptopenjdk.spi.AOException;
 import com.io7m.adoptopenjdk.spi.AORelease;
+import com.io7m.adoptopenjdk.spi.AOVariant;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -158,6 +159,25 @@ public int rateLimitRemaining()
     return this.rate_limit.remaining;
   }
 
+  @Override
+  public List<AOVariant> variants()
+    throws AOException
+  {
+    this.checkRateLimitRemaining();
+
+    final URI target = URI.create("https://api.adoptopenjdk.net/variants");
+    try (AOv1HTTPConnectionType connection =
+           this.connections.get(target, standardProperties())) {
+
+      this.rate_limit = rateLimitForConnection(connection);
+      try (InputStream stream = connection.input()) {
+        return this.parser.parseVariants(target, stream);
+      }
+    } catch (final IOException e) {
+      throw new AOException(e.getMessage(), e);
+    }
+  }
+
   @Override
   public List<AORelease> releasesForVariant(final String variant)
     throws AOException
diff --git a/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1RequestsType.java b/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1RequestsType.java
index f8e3731..eb69855 100644
--- a/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1RequestsType.java
+++ b/com.io7m.adoptopenjdk.v1/src/main/java/com/io7m/adoptopenjdk/v1/AOv1RequestsType.java
@@ -20,6 +20,7 @@
 import com.io7m.adoptopenjdk.spi.AOException;
 import com.io7m.adoptopenjdk.spi.AORelease;
 import com.io7m.adoptopenjdk.spi.AOReleases;
+import com.io7m.adoptopenjdk.spi.AOVariant;
 
 import java.util.List;
 import java.util.Objects;
@@ -35,6 +36,10 @@ public interface AOv1RequestsType extends AOAPIRequestsType
   @Override
   int rateLimitRemaining();
 
+  @Override
+  List<AOVariant> variants()
+    throws AOException;
+
   @Override
   List<AORelease> releasesForVariant(
     String variant)