diff --git a/src/backend/graphql/__snapshots__/queries.test.js.snap b/src/backend/graphql/__snapshots__/queries.test.js.snap
new file mode 100644
index 0000000..bed8d50
--- /dev/null
+++ b/src/backend/graphql/__snapshots__/queries.test.js.snap
@@ -0,0 +1,961 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`queries complex object stringification should build the object 1`] = `
+Object {
+  "data": Object {
+    "exampleBoolean": Object {
+      "data": true,
+      "type": "LITERAL",
+    },
+    "exampleEnum": Object {
+      "data": "WORLD",
+      "type": "ENUM",
+    },
+    "exampleList": Object {
+      "data": Array [
+        Object {
+          "data": 12,
+          "type": "LITERAL",
+        },
+        Object {
+          "data": 14,
+          "type": "LITERAL",
+        },
+        Object {
+          "data": 16,
+          "type": "LITERAL",
+        },
+      ],
+      "type": "LIST",
+    },
+    "exampleNull": Object {
+      "data": null,
+      "type": "LITERAL",
+    },
+    "exampleNumber": Object {
+      "data": 123,
+      "type": "LITERAL",
+    },
+    "exampleObject": Object {
+      "data": Object {
+        "roses": Object {
+          "data": "red",
+          "type": "LITERAL",
+        },
+        "violets": Object {
+          "data": "blue",
+          "type": "LITERAL",
+        },
+      },
+      "type": "OBJECT",
+    },
+    "exampleString": Object {
+      "data": "hello",
+      "type": "LITERAL",
+    },
+    "exampleVariable": Object {
+      "data": "widget",
+      "type": "VARIABLE",
+    },
+    "nestedList": Object {
+      "data": Array [
+        Object {
+          "data": Array [
+            Object {
+              "data": "w",
+              "type": "LITERAL",
+            },
+            Object {
+              "data": "x",
+              "type": "LITERAL",
+            },
+          ],
+          "type": "LIST",
+        },
+        Object {
+          "data": Array [
+            Object {
+              "data": "y",
+              "type": "LITERAL",
+            },
+            Object {
+              "data": "z",
+              "type": "LITERAL",
+            },
+          ],
+          "type": "LIST",
+        },
+      ],
+      "type": "LIST",
+    },
+    "nestedObject": Object {
+      "data": Object {
+        "english": Object {
+          "data": Object {
+            "n1": Object {
+              "data": "one",
+              "type": "LITERAL",
+            },
+            "n2": Object {
+              "data": "two",
+              "type": "LITERAL",
+            },
+          },
+          "type": "OBJECT",
+        },
+        "greek": Object {
+          "data": Object {
+            "n1": Object {
+              "data": "ένα",
+              "type": "LITERAL",
+            },
+            "n2": Object {
+              "data": "δύο",
+              "type": "LITERAL",
+            },
+          },
+          "type": "OBJECT",
+        },
+      },
+      "type": "OBJECT",
+    },
+  },
+  "type": "OBJECT",
+}
+`;
+
+exports[`queries complex object stringification should work inline 1`] = `"{ exampleNumber: 123 exampleString: \\"hello\\" exampleBoolean: true exampleNull: null exampleEnum: WORLD exampleVariable: $widget exampleList: [ 12 14 16 ] exampleObject: { roses: \\"red\\" violets: \\"blue\\" } nestedList: [ [ \\"w\\" \\"x\\" ] [ \\"y\\" \\"z\\" ] ] nestedObject: { english: { n1: \\"one\\" n2: \\"two\\" } greek: { n1: \\"ένα\\" n2: \\"δύο\\" } } }"`;
+
+exports[`queries complex object stringification should work multiline 1`] = `
+"{
+  exampleNumber:
+    123
+  exampleString:
+    \\"hello\\"
+  exampleBoolean:
+    true
+  exampleNull:
+    null
+  exampleEnum:
+    WORLD
+  exampleVariable:
+    $widget
+  exampleList:
+    [
+      12
+      14
+      16
+    ]
+  exampleObject:
+    {
+      roses:
+        \\"red\\"
+      violets:
+        \\"blue\\"
+    }
+  nestedList:
+    [
+      [
+        \\"w\\"
+        \\"x\\"
+      ]
+      [
+        \\"y\\"
+        \\"z\\"
+      ]
+    ]
+  nestedObject:
+    {
+      english:
+        {
+          n1:
+            \\"one\\"
+          n2:
+            \\"two\\"
+        }
+      greek:
+        {
+          n1:
+            \\"ένα\\"
+          n2:
+            \\"δύο\\"
+        }
+    }
+}"
+`;
+
+exports[`queries end-to-end-test cases for a query using lots of features should build the query 1`] = `
+Array [
+  Object {
+    "name": "QueryWithParameters",
+    "params": Array [
+      Object {
+        "name": "qp1",
+        "type": "String!",
+      },
+      Object {
+        "name": "qp2",
+        "type": "String!",
+      },
+    ],
+    "selections": Array [
+      Object {
+        "args": Object {
+          "id": Object {
+            "data": 12345,
+            "type": "LITERAL",
+          },
+          "name": Object {
+            "data": "qp1",
+            "type": "VARIABLE",
+          },
+        },
+        "name": "thing",
+        "selections": Array [
+          Object {
+            "args": Object {
+              "tasty": Object {
+                "data": true,
+                "type": "LITERAL",
+              },
+              "type": Object {
+                "data": "APPLE",
+                "type": "ENUM",
+              },
+            },
+            "name": "fruit",
+            "selections": Array [],
+            "type": "FIELD",
+          },
+          Object {
+            "fragmentName": "otherThings",
+            "type": "FRAGMENT_SPREAD",
+          },
+        ],
+        "type": "FIELD",
+      },
+      Object {
+        "args": Object {},
+        "name": "more",
+        "selections": Array [
+          Object {
+            "selections": Array [
+              Object {
+                "args": Object {},
+                "name": "mcguffins",
+                "selections": Array [
+                  Object {
+                    "args": Object {},
+                    "name": "quantity",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                ],
+                "type": "FIELD",
+              },
+              Object {
+                "args": Object {
+                  "state": Object {
+                    "data": "SLIMY",
+                    "type": "ENUM",
+                  },
+                },
+                "name": "slime",
+                "selections": Array [
+                  Object {
+                    "args": Object {},
+                    "name": "availability",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                ],
+                "type": "FIELD",
+              },
+            ],
+            "type": "INLINE_FRAGMENT",
+            "typeCondition": "Widget",
+          },
+          Object {
+            "selections": Array [
+              Object {
+                "args": Object {
+                  "attributes": Object {
+                    "data": Object {
+                      "shaft": Object {
+                        "data": null,
+                        "type": "LITERAL",
+                      },
+                      "teeth": Object {
+                        "data": Array [
+                          Object {
+                            "data": 12,
+                            "type": "LITERAL",
+                          },
+                          Object {
+                            "data": 14,
+                            "type": "LITERAL",
+                          },
+                          Object {
+                            "data": 16,
+                            "type": "LITERAL",
+                          },
+                        ],
+                        "type": "LIST",
+                      },
+                    },
+                    "type": "OBJECT",
+                  },
+                },
+                "name": "cogs",
+                "selections": Array [],
+                "type": "FIELD",
+              },
+            ],
+            "type": "INLINE_FRAGMENT",
+            "typeCondition": "Gizmo",
+          },
+        ],
+        "type": "FIELD",
+      },
+    ],
+    "type": "QUERY",
+  },
+  Object {
+    "name": "QueryWithoutParameters",
+    "params": Array [],
+    "selections": Array [
+      Object {
+        "args": Object {},
+        "name": "rateLimit",
+        "selections": Array [
+          Object {
+            "args": Object {},
+            "name": "remaining",
+            "selections": Array [],
+            "type": "FIELD",
+          },
+        ],
+        "type": "FIELD",
+      },
+    ],
+    "type": "QUERY",
+  },
+  Object {
+    "name": "otherThings",
+    "selections": Array [
+      Object {
+        "args": Object {},
+        "name": "__typename",
+        "selections": Array [],
+        "type": "FIELD",
+      },
+      Object {
+        "args": Object {},
+        "name": "quality",
+        "selections": Array [],
+        "type": "FIELD",
+      },
+    ],
+    "type": "FRAGMENT",
+    "typeCondition": "Thing",
+  },
+]
+`;
+
+exports[`queries end-to-end-test cases for a query using lots of features should stringify as inline 1`] = `"query QueryWithParameters($qp1: String! $qp2: String!) { thing(id: 12345 name: $qp1) { fruit(type: APPLE tasty: true) ...otherThings } more { ... on Widget { mcguffins { quantity } slime(state: SLIMY) { availability } } ... on Gizmo { cogs(attributes: { teeth: [ 12 14 16 ] shaft: null }) } } } query QueryWithoutParameters { rateLimit { remaining } } fragment otherThings on Thing { __typename quality }"`;
+
+exports[`queries end-to-end-test cases for a query using lots of features should stringify as multiline 1`] = `
+"query QueryWithParameters($qp1: String! $qp2: String!) {
+  thing(id: 12345 name: $qp1) {
+    fruit(type: APPLE tasty: true)
+    ...otherThings
+  }
+  more {
+    ... on Widget {
+      mcguffins {
+        quantity
+      }
+      slime(state: SLIMY) {
+        availability
+      }
+    }
+    ... on Gizmo {
+      cogs(attributes: { teeth: [ 12 14 16 ] shaft: null })
+    }
+  }
+}
+query QueryWithoutParameters {
+  rateLimit {
+    remaining
+  }
+}
+fragment otherThings on Thing {
+  __typename
+  quality
+}"
+`;
+
+exports[`queries end-to-end-test cases for a useful query should build the query 1`] = `
+Array [
+  Object {
+    "name": "FetchData",
+    "params": Array [
+      Object {
+        "name": "repoOwner",
+        "type": "String!",
+      },
+      Object {
+        "name": "repoName",
+        "type": "String!",
+      },
+    ],
+    "selections": Array [
+      Object {
+        "args": Object {
+          "name": Object {
+            "data": "repoName",
+            "type": "VARIABLE",
+          },
+          "owner": Object {
+            "data": "repoOwner",
+            "type": "VARIABLE",
+          },
+        },
+        "name": "repository",
+        "selections": Array [
+          Object {
+            "args": Object {
+              "first": Object {
+                "data": 100,
+                "type": "LITERAL",
+              },
+            },
+            "name": "issues",
+            "selections": Array [
+              Object {
+                "args": Object {},
+                "name": "pageInfo",
+                "selections": Array [
+                  Object {
+                    "args": Object {},
+                    "name": "hasNextPage",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                ],
+                "type": "FIELD",
+              },
+              Object {
+                "args": Object {},
+                "name": "nodes",
+                "selections": Array [
+                  Object {
+                    "args": Object {},
+                    "name": "id",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {},
+                    "name": "title",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {},
+                    "name": "body",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {},
+                    "name": "number",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {},
+                    "name": "author",
+                    "selections": Array [
+                      Object {
+                        "fragmentName": "whoami",
+                        "type": "FRAGMENT_SPREAD",
+                      },
+                    ],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {
+                      "first": Object {
+                        "data": 20,
+                        "type": "LITERAL",
+                      },
+                    },
+                    "name": "comments",
+                    "selections": Array [
+                      Object {
+                        "args": Object {},
+                        "name": "pageInfo",
+                        "selections": Array [
+                          Object {
+                            "args": Object {},
+                            "name": "hasNextPage",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                        ],
+                        "type": "FIELD",
+                      },
+                      Object {
+                        "args": Object {},
+                        "name": "nodes",
+                        "selections": Array [
+                          Object {
+                            "args": Object {},
+                            "name": "id",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                          Object {
+                            "args": Object {},
+                            "name": "author",
+                            "selections": Array [
+                              Object {
+                                "fragmentName": "whoami",
+                                "type": "FRAGMENT_SPREAD",
+                              },
+                            ],
+                            "type": "FIELD",
+                          },
+                          Object {
+                            "args": Object {},
+                            "name": "body",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                          Object {
+                            "args": Object {},
+                            "name": "url",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                        ],
+                        "type": "FIELD",
+                      },
+                    ],
+                    "type": "FIELD",
+                  },
+                ],
+                "type": "FIELD",
+              },
+            ],
+            "type": "FIELD",
+          },
+          Object {
+            "args": Object {
+              "first": Object {
+                "data": 100,
+                "type": "LITERAL",
+              },
+            },
+            "name": "pullRequests",
+            "selections": Array [
+              Object {
+                "args": Object {},
+                "name": "pageInfo",
+                "selections": Array [
+                  Object {
+                    "args": Object {},
+                    "name": "hasNextPage",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                ],
+                "type": "FIELD",
+              },
+              Object {
+                "args": Object {},
+                "name": "nodes",
+                "selections": Array [
+                  Object {
+                    "args": Object {},
+                    "name": "id",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {},
+                    "name": "title",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {},
+                    "name": "body",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {},
+                    "name": "number",
+                    "selections": Array [],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {},
+                    "name": "author",
+                    "selections": Array [
+                      Object {
+                        "fragmentName": "whoami",
+                        "type": "FRAGMENT_SPREAD",
+                      },
+                    ],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {
+                      "first": Object {
+                        "data": 20,
+                        "type": "LITERAL",
+                      },
+                    },
+                    "name": "comments",
+                    "selections": Array [
+                      Object {
+                        "args": Object {},
+                        "name": "pageInfo",
+                        "selections": Array [
+                          Object {
+                            "args": Object {},
+                            "name": "hasNextPage",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                        ],
+                        "type": "FIELD",
+                      },
+                      Object {
+                        "args": Object {},
+                        "name": "nodes",
+                        "selections": Array [
+                          Object {
+                            "args": Object {},
+                            "name": "id",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                          Object {
+                            "args": Object {},
+                            "name": "author",
+                            "selections": Array [
+                              Object {
+                                "fragmentName": "whoami",
+                                "type": "FRAGMENT_SPREAD",
+                              },
+                            ],
+                            "type": "FIELD",
+                          },
+                          Object {
+                            "args": Object {},
+                            "name": "body",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                          Object {
+                            "args": Object {},
+                            "name": "url",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                        ],
+                        "type": "FIELD",
+                      },
+                    ],
+                    "type": "FIELD",
+                  },
+                  Object {
+                    "args": Object {
+                      "first": Object {
+                        "data": 10,
+                        "type": "LITERAL",
+                      },
+                    },
+                    "name": "reviews",
+                    "selections": Array [
+                      Object {
+                        "args": Object {},
+                        "name": "pageInfo",
+                        "selections": Array [
+                          Object {
+                            "args": Object {},
+                            "name": "hasNextPage",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                        ],
+                        "type": "FIELD",
+                      },
+                      Object {
+                        "args": Object {},
+                        "name": "nodes",
+                        "selections": Array [
+                          Object {
+                            "args": Object {},
+                            "name": "id",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                          Object {
+                            "args": Object {},
+                            "name": "body",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                          Object {
+                            "args": Object {},
+                            "name": "author",
+                            "selections": Array [
+                              Object {
+                                "fragmentName": "whoami",
+                                "type": "FRAGMENT_SPREAD",
+                              },
+                            ],
+                            "type": "FIELD",
+                          },
+                          Object {
+                            "args": Object {},
+                            "name": "state",
+                            "selections": Array [],
+                            "type": "FIELD",
+                          },
+                          Object {
+                            "args": Object {
+                              "first": Object {
+                                "data": 10,
+                                "type": "LITERAL",
+                              },
+                            },
+                            "name": "comments",
+                            "selections": Array [
+                              Object {
+                                "args": Object {},
+                                "name": "pageInfo",
+                                "selections": Array [
+                                  Object {
+                                    "args": Object {},
+                                    "name": "hasNextPage",
+                                    "selections": Array [],
+                                    "type": "FIELD",
+                                  },
+                                ],
+                                "type": "FIELD",
+                              },
+                              Object {
+                                "args": Object {},
+                                "name": "nodes",
+                                "selections": Array [
+                                  Object {
+                                    "args": Object {},
+                                    "name": "id",
+                                    "selections": Array [],
+                                    "type": "FIELD",
+                                  },
+                                  Object {
+                                    "args": Object {},
+                                    "name": "body",
+                                    "selections": Array [],
+                                    "type": "FIELD",
+                                  },
+                                  Object {
+                                    "args": Object {},
+                                    "name": "author",
+                                    "selections": Array [
+                                      Object {
+                                        "fragmentName": "whoami",
+                                        "type": "FRAGMENT_SPREAD",
+                                      },
+                                    ],
+                                    "type": "FIELD",
+                                  },
+                                ],
+                                "type": "FIELD",
+                              },
+                            ],
+                            "type": "FIELD",
+                          },
+                        ],
+                        "type": "FIELD",
+                      },
+                    ],
+                    "type": "FIELD",
+                  },
+                ],
+                "type": "FIELD",
+              },
+            ],
+            "type": "FIELD",
+          },
+        ],
+        "type": "FIELD",
+      },
+    ],
+    "type": "QUERY",
+  },
+  Object {
+    "name": "whoami",
+    "selections": Array [
+      Object {
+        "args": Object {},
+        "name": "__typename",
+        "selections": Array [],
+        "type": "FIELD",
+      },
+      Object {
+        "args": Object {},
+        "name": "login",
+        "selections": Array [],
+        "type": "FIELD",
+      },
+      Object {
+        "selections": Array [
+          Object {
+            "args": Object {},
+            "name": "id",
+            "selections": Array [],
+            "type": "FIELD",
+          },
+        ],
+        "type": "INLINE_FRAGMENT",
+        "typeCondition": "User",
+      },
+      Object {
+        "selections": Array [
+          Object {
+            "args": Object {},
+            "name": "id",
+            "selections": Array [],
+            "type": "FIELD",
+          },
+        ],
+        "type": "INLINE_FRAGMENT",
+        "typeCondition": "Organization",
+      },
+      Object {
+        "selections": Array [
+          Object {
+            "args": Object {},
+            "name": "id",
+            "selections": Array [],
+            "type": "FIELD",
+          },
+        ],
+        "type": "INLINE_FRAGMENT",
+        "typeCondition": "Bot",
+      },
+    ],
+    "type": "FRAGMENT",
+    "typeCondition": "Actor",
+  },
+]
+`;
+
+exports[`queries end-to-end-test cases for a useful query should stringify as inline 1`] = `"query FetchData($repoOwner: String! $repoName: String!) { repository(owner: $repoOwner name: $repoName) { issues(first: 100) { pageInfo { hasNextPage } nodes { id title body number author { ...whoami } comments(first: 20) { pageInfo { hasNextPage } nodes { id author { ...whoami } body url } } } } pullRequests(first: 100) { pageInfo { hasNextPage } nodes { id title body number author { ...whoami } comments(first: 20) { pageInfo { hasNextPage } nodes { id author { ...whoami } body url } } reviews(first: 10) { pageInfo { hasNextPage } nodes { id body author { ...whoami } state comments(first: 10) { pageInfo { hasNextPage } nodes { id body author { ...whoami } } } } } } } } } fragment whoami on Actor { __typename login ... on User { id } ... on Organization { id } ... on Bot { id } }"`;
+
+exports[`queries end-to-end-test cases for a useful query should stringify as multiline 1`] = `
+"query FetchData($repoOwner: String! $repoName: String!) {
+  repository(owner: $repoOwner name: $repoName) {
+    issues(first: 100) {
+      pageInfo {
+        hasNextPage
+      }
+      nodes {
+        id
+        title
+        body
+        number
+        author {
+          ...whoami
+        }
+        comments(first: 20) {
+          pageInfo {
+            hasNextPage
+          }
+          nodes {
+            id
+            author {
+              ...whoami
+            }
+            body
+            url
+          }
+        }
+      }
+    }
+    pullRequests(first: 100) {
+      pageInfo {
+        hasNextPage
+      }
+      nodes {
+        id
+        title
+        body
+        number
+        author {
+          ...whoami
+        }
+        comments(first: 20) {
+          pageInfo {
+            hasNextPage
+          }
+          nodes {
+            id
+            author {
+              ...whoami
+            }
+            body
+            url
+          }
+        }
+        reviews(first: 10) {
+          pageInfo {
+            hasNextPage
+          }
+          nodes {
+            id
+            body
+            author {
+              ...whoami
+            }
+            state
+            comments(first: 10) {
+              pageInfo {
+                hasNextPage
+              }
+              nodes {
+                id
+                body
+                author {
+                  ...whoami
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}
+fragment whoami on Actor {
+  __typename
+  login
+  ... on User {
+    id
+  }
+  ... on Organization {
+    id
+  }
+  ... on Bot {
+    id
+  }
+}"
+`;
diff --git a/src/backend/graphql/queries.js b/src/backend/graphql/queries.js
new file mode 100644
index 0000000..f6be94c
--- /dev/null
+++ b/src/backend/graphql/queries.js
@@ -0,0 +1,398 @@
+// @flow
+
+/**
+ * GraphQL structured query data format.
+ *
+ * Main module exports:
+ *   - lots of types for various GraphQL language constructs
+ *   - the `build` object, providing a fluent builder API
+ *   - the `stringify` object, and particularly `stringify.body`
+ *   - the two layout strategies `multilineLayout` and `inlineLayout`
+ */
+
+export type Body = Definition[];
+
+export type Definition = QueryDefinition | FragmentDefinition;
+
+// We only need opaque type handles; no need to embed the GraphQL type
+// system into Flow.
+export type GraphQLType = string;
+
+export type QueryDefinition = {|
+  +type: "QUERY",
+  +name: string,
+  +params: Parameter[],
+  +selections: Selection[],
+|};
+export type Parameter = {|+name: string, +type: GraphQLType|};
+
+export type FragmentDefinition = {|
+  +type: "FRAGMENT",
+  +name: string,
+  +typeCondition: GraphQLType,
+  +selections: Selection[],
+|};
+
+export type Selection = Field | FragmentSpread | InlineFragment;
+export type Field = {|
+  +type: "FIELD",
+  +name: string,
+  +args: Arguments,
+  +selections: Selection[],
+|};
+export type FragmentSpread = {|
+  +type: "FRAGMENT_SPREAD",
+  +fragmentName: string,
+|};
+export type InlineFragment = {|
+  +type: "INLINE_FRAGMENT",
+  +typeCondition: ?GraphQLType,
+  +selections: Selection[],
+|};
+
+export type Arguments = {[string]: Value};
+export type Value =
+  | VariableValue
+  | LiteralValue
+  | EnumValue
+  | ListValue
+  | ObjectValue;
+export type VariableValue = {|+type: "VARIABLE", +data: string|};
+export type LiteralValue = {|
+  +type: "LITERAL",
+  +data: number | string | boolean | null,
+|};
+export type EnumValue = {|+type: "ENUM", +data: string|};
+export type ListValue = {|+type: "LIST", +data: Value[]|};
+export type ObjectValue = {|+type: "OBJECT", +data: {[string]: Value}|};
+
+export const build = {
+  query(
+    name: string,
+    params: Parameter[],
+    selections: Selection[]
+  ): QueryDefinition {
+    return {
+      type: "QUERY",
+      name,
+      params,
+      selections,
+    };
+  },
+
+  param(name: string, type: GraphQLType): Parameter {
+    return {name, type};
+  },
+
+  fragment(
+    name: string,
+    typeCondition: GraphQLType,
+    selections: Selection[]
+  ): FragmentDefinition {
+    return {
+      type: "FRAGMENT",
+      name,
+      typeCondition,
+      selections,
+    };
+  },
+
+  field(name: string, args: ?Arguments, selections: ?(Selection[])): Field {
+    return {
+      type: "FIELD",
+      name,
+      args: args || {},
+      selections: selections || [],
+    };
+  },
+
+  fragmentSpread(fragmentName: string): FragmentSpread {
+    return {
+      type: "FRAGMENT_SPREAD",
+      fragmentName,
+    };
+  },
+
+  inlineFragment(
+    typeCondition: ?GraphQLType,
+    selections: Selection[]
+  ): InlineFragment {
+    return {
+      type: "INLINE_FRAGMENT",
+      typeCondition,
+      selections,
+    };
+  },
+
+  variable(name: string): VariableValue {
+    return {
+      type: "VARIABLE",
+      data: name,
+    };
+  },
+
+  literal(value: number | string | boolean | null): LiteralValue {
+    return {
+      type: "LITERAL",
+      data: value,
+    };
+  },
+
+  enumLiteral(value: string): EnumValue {
+    return {
+      type: "ENUM",
+      data: value,
+    };
+  },
+
+  list(data: Value[]): ListValue {
+    return {
+      type: "LIST",
+      data: data,
+    };
+  },
+
+  object(data: {[string]: Value}): ObjectValue {
+    return {
+      type: "OBJECT",
+      data: data,
+    };
+  },
+};
+
+/**
+ * A strategy for stringifying a sequence of GraphQL language tokens.
+ */
+export interface LayoutStrategy {
+  // Lay out a group of tokens that should be treated atomically.
+  atom(line: string): string;
+
+  // Join groups of tokens. The elements should be the results of calls
+  // to `atom` (or other `join`s).
+  join(lines: string[]): string;
+
+  // Get a strategy for the next level of nesting. For instance, if this
+  // object lays out its result over multiple lines, then this method
+  // might produce a strategy with one extra level of indentation.
+  next(): LayoutStrategy;
+}
+
+/**
+ * Create a layout strategy that lays out text over multiple lines,
+ * indenting with the given tab string (such as "\t" or "  ").
+ */
+export function multilineLayout(tab: string): LayoutStrategy {
+  function strategy(indentLevel: number) {
+    return {
+      atom: (line: string) => {
+        const indentation = Array(indentLevel)
+          .fill(tab)
+          .join("");
+        return indentation + line;
+      },
+      join: (xs: string[]) => xs.join("\n"),
+      next: () => strategy(indentLevel + 1),
+    };
+  }
+  return strategy(0);
+}
+
+/**
+ * Create a layout strategy that lays out all text on one line.
+ */
+export function inlineLayout(): LayoutStrategy {
+  const result = {
+    atom: (line) => line,
+    join: (xs) => xs.join(" "),
+    next: () => result,
+  };
+  return result;
+}
+
+/*
+ * Map a stringification function across a list, and join the results
+ * with a formatter.
+ */
+function formatList<T>(
+  values: T[],
+  subformatter: (value: T, ls: LayoutStrategy) => string,
+  ls: LayoutStrategy
+): string {
+  return ls.join(values.map((x) => subformatter(x, ls)));
+}
+
+/*
+ * Map a stringification function across the values of an object, and
+ * join the keys and their corresponding results with a formatter.
+ */
+function formatObject<T>(
+  object: {[string]: T},
+  subformatter: (value: T, ls: LayoutStrategy) => string,
+  ls: LayoutStrategy
+): string {
+  function formatKey(k: string, ls: LayoutStrategy): string {
+    return ls.join([ls.atom(`${k}:`), subformatter(object[k], ls.next())]);
+  }
+  return formatList(Object.keys(object), formatKey, ls);
+}
+
+export const stringify = {
+  body(body: Body, ls: LayoutStrategy): string {
+    return formatList(body, stringify.definition, ls);
+  },
+
+  definition(definition: Definition, ls: LayoutStrategy): string {
+    switch (definition.type) {
+      case "QUERY":
+        return stringify.queryDefinition(definition, ls);
+      case "FRAGMENT":
+        return stringify.fragmentDefinition(definition, ls);
+      default:
+        throw new Error(`Unknown definition type: ${definition.type}`);
+    }
+  },
+
+  queryDefinition(query: QueryDefinition, ls: LayoutStrategy): string {
+    const paramsPart = (() => {
+      if (query.params.length === 0) {
+        return "";
+      } else {
+        const items = formatList(
+          query.params,
+          stringify.parameter,
+          inlineLayout()
+        );
+        return `(${items})`;
+      }
+    })();
+    const selectionsPart = formatList(
+      query.selections,
+      stringify.selection,
+      ls.next()
+    );
+    return ls.join([
+      ls.atom(`query ${query.name}${paramsPart} {`),
+      selectionsPart,
+      ls.atom("}"),
+    ]);
+  },
+
+  parameter(parameter: Parameter, ls: LayoutStrategy): string {
+    return ls.atom(`\$${parameter.name}: ${parameter.type}`);
+  },
+
+  fragmentDefinition(fragment: FragmentDefinition, ls: LayoutStrategy): string {
+    const selectionsPart = formatList(
+      fragment.selections,
+      stringify.selection,
+      ls.next()
+    );
+    return ls.join([
+      ls.atom(`fragment ${fragment.name} on ${fragment.typeCondition} {`),
+      selectionsPart,
+      ls.atom("}"),
+    ]);
+  },
+
+  selection(selection: Selection, ls: LayoutStrategy): string {
+    switch (selection.type) {
+      case "FIELD":
+        return stringify.field(selection, ls);
+      case "FRAGMENT_SPREAD":
+        return stringify.fragmentSpread(selection, ls);
+      case "INLINE_FRAGMENT":
+        return stringify.inlineFragment(selection, ls);
+      default:
+        throw new Error(`Unknown selection type: ${selection.type}`);
+    }
+  },
+
+  field(field: Field, ls: LayoutStrategy): string {
+    const argsPart = (() => {
+      if (Object.keys(field.args).length === 0) {
+        return "";
+      } else {
+        const args = formatObject(field.args, stringify.value, inlineLayout());
+        return `(${args})`;
+      }
+    })();
+    if (field.selections.length === 0) {
+      return ls.atom(`${field.name}${argsPart}`);
+    } else {
+      const selectionsPart = formatList(
+        field.selections,
+        stringify.selection,
+        ls.next()
+      );
+      return ls.join([
+        ls.atom(`${field.name}${argsPart} {`),
+        selectionsPart,
+        ls.atom("}"),
+      ]);
+    }
+  },
+
+  fragmentSpread(fs: FragmentSpread, ls: LayoutStrategy): string {
+    return ls.atom(`...${fs.fragmentName}`);
+  },
+
+  inlineFragment(fragment: InlineFragment, ls: LayoutStrategy): string {
+    const typeConditionPart =
+      fragment.typeCondition == null ? "" : ` on ${fragment.typeCondition}`;
+    const selectionsPart = formatList(
+      fragment.selections,
+      stringify.selection,
+      ls.next()
+    );
+    return ls.join([
+      ls.atom(`...${typeConditionPart} {`),
+      selectionsPart,
+      ls.atom("}"),
+    ]);
+  },
+
+  value(value: Value, ls: LayoutStrategy): string {
+    switch (value.type) {
+      case "VARIABLE":
+        return stringify.variableValue(value, ls);
+      case "LITERAL":
+        return stringify.literalValue(value, ls);
+      case "ENUM":
+        return stringify.enumValue(value, ls);
+      case "LIST":
+        return stringify.listValue(value, ls);
+      case "OBJECT":
+        return stringify.objectValue(value, ls);
+      default:
+        throw new Error(`Unknown value type: ${value.type}`);
+    }
+  },
+
+  variableValue(value: VariableValue, ls: LayoutStrategy): string {
+    return ls.atom(`\$${value.data}`);
+  },
+
+  literalValue(value: LiteralValue, ls: LayoutStrategy): string {
+    return ls.atom(JSON.stringify(value.data));
+  },
+
+  enumValue(value: EnumValue, ls: LayoutStrategy): string {
+    return ls.atom(value.data);
+  },
+
+  listValue(value: ListValue, ls: LayoutStrategy): string {
+    return ls.join([
+      ls.atom("["),
+      formatList(value.data, stringify.value, ls.next()),
+      ls.atom("]"),
+    ]);
+  },
+
+  objectValue(value: ObjectValue, ls: LayoutStrategy): string {
+    return ls.join([
+      ls.atom("{"),
+      formatObject(value.data, stringify.value, ls.next()),
+      ls.atom("}"),
+    ]);
+  },
+};
diff --git a/src/backend/graphql/queries.test.js b/src/backend/graphql/queries.test.js
new file mode 100644
index 0000000..52bdec7
--- /dev/null
+++ b/src/backend/graphql/queries.test.js
@@ -0,0 +1,200 @@
+// @flow
+
+import type {Body} from "./queries";
+import {build, stringify, multilineLayout, inlineLayout} from "./queries";
+
+describe("queries", () => {
+  describe("end-to-end-test cases", () => {
+    const testCases = {
+      "a query using lots of features": featurefulQuery,
+      "a useful query": usefulQuery,
+    };
+    Object.keys(testCases).forEach((key) => {
+      describe(`for ${key}`, () => {
+        const testCase = testCases[key];
+        it("should build the query", () => {
+          expect(testCase()).toMatchSnapshot();
+        });
+        it("should stringify as multiline", () => {
+          const result = stringify.body(testCase(), multilineLayout("  "));
+          expect(result).toMatchSnapshot();
+        });
+        it("should stringify as inline", () => {
+          const result = stringify.body(testCase(), inlineLayout());
+          expect(result).toMatchSnapshot();
+        });
+      });
+    });
+  });
+  describe("complex object stringification", () => {
+    const object = () => {
+      const b = build;
+      return b.object({
+        exampleNumber: b.literal(123),
+        exampleString: b.literal("hello"),
+        exampleBoolean: b.literal(true),
+        exampleNull: b.literal(null),
+        exampleEnum: b.enumLiteral("WORLD"),
+        exampleVariable: b.variable("widget"),
+        exampleList: b.list([b.literal(12), b.literal(14), b.literal(16)]),
+        exampleObject: b.object({
+          roses: b.literal("red"),
+          violets: b.literal("blue"),
+        }),
+        nestedList: b.list([
+          b.list([b.literal("w"), b.literal("x")]),
+          b.list([b.literal("y"), b.literal("z")]),
+        ]),
+        nestedObject: b.object({
+          english: b.object({
+            n1: b.literal("one"),
+            n2: b.literal("two"),
+          }),
+          greek: b.object({
+            n1: b.literal("ένα"),
+            n2: b.literal("δύο"),
+          }),
+        }),
+      });
+    };
+    it("should build the object", () => {
+      expect(object()).toMatchSnapshot();
+    });
+    it("should work multiline", () => {
+      const result = stringify.value(object(), multilineLayout("  "));
+      expect(result).toMatchSnapshot();
+    });
+    it("should work inline", () => {
+      const result = stringify.value(object(), inlineLayout());
+      expect(result).toMatchSnapshot();
+    });
+  });
+});
+
+function featurefulQuery(): Body {
+  const b = build;
+  const body: Body = [
+    b.query(
+      "QueryWithParameters",
+      [b.param("qp1", "String!"), b.param("qp2", "String!")],
+      [
+        b.field("thing", {id: b.literal(12345), name: b.variable("qp1")}, [
+          b.field("fruit", {
+            type: b.enumLiteral("APPLE"),
+            tasty: b.literal(true),
+          }),
+          b.fragmentSpread("otherThings"),
+        ]),
+        b.field("more", {}, [
+          b.inlineFragment("Widget", [
+            b.field("mcguffins", {}, [b.field("quantity")]),
+            b.field("slime", {state: b.enumLiteral("SLIMY")}, [
+              b.field("availability"),
+            ]),
+          ]),
+          b.inlineFragment("Gizmo", [
+            b.field("cogs", {
+              attributes: b.object({
+                teeth: b.list([b.literal(12), b.literal(14), b.literal(16)]),
+                shaft: b.literal(null),
+              }),
+            }),
+          ]),
+        ]),
+      ]
+    ),
+    b.query(
+      "QueryWithoutParameters",
+      [],
+      [b.field("rateLimit", {}, [b.field("remaining")])]
+    ),
+    b.fragment("otherThings", "Thing", [
+      b.field("__typename"),
+      b.field("quality"),
+    ]),
+  ];
+  return body;
+}
+
+function usefulQuery(): Body {
+  const b = build;
+  const makePageInfo = () => b.field("pageInfo", {}, [b.field("hasNextPage")]);
+  const makeAuthor = () => b.field("author", {}, [b.fragmentSpread("whoami")]);
+  const body: Body = [
+    b.query(
+      "FetchData",
+      [b.param("repoOwner", "String!"), b.param("repoName", "String!")],
+      [
+        b.field(
+          "repository",
+          {owner: b.variable("repoOwner"), name: b.variable("repoName")},
+          [
+            b.field("issues", {first: b.literal(100)}, [
+              makePageInfo(),
+              b.field("nodes", {}, [
+                b.field("id"),
+                b.field("title"),
+                b.field("body"),
+                b.field("number"),
+                makeAuthor(),
+                b.field("comments", {first: b.literal(20)}, [
+                  makePageInfo(),
+                  b.field("nodes", {}, [
+                    b.field("id"),
+                    makeAuthor(),
+                    b.field("body"),
+                    b.field("url"),
+                  ]),
+                ]),
+              ]),
+            ]),
+            b.field("pullRequests", {first: b.literal(100)}, [
+              makePageInfo(),
+              b.field("nodes", {}, [
+                b.field("id"),
+                b.field("title"),
+                b.field("body"),
+                b.field("number"),
+                makeAuthor(),
+                b.field("comments", {first: b.literal(20)}, [
+                  makePageInfo(),
+                  b.field("nodes", {}, [
+                    b.field("id"),
+                    makeAuthor(),
+                    b.field("body"),
+                    b.field("url"),
+                  ]),
+                ]),
+                b.field("reviews", {first: b.literal(10)}, [
+                  makePageInfo(),
+                  b.field("nodes", {}, [
+                    b.field("id"),
+                    b.field("body"),
+                    makeAuthor(),
+                    b.field("state"),
+                    b.field("comments", {first: b.literal(10)}, [
+                      makePageInfo(),
+                      b.field("nodes", {}, [
+                        b.field("id"),
+                        b.field("body"),
+                        makeAuthor(),
+                      ]),
+                    ]),
+                  ]),
+                ]),
+              ]),
+            ]),
+          ]
+        ),
+      ]
+    ),
+    b.fragment("whoami", "Actor", [
+      b.field("__typename"),
+      b.field("login"),
+      b.inlineFragment("User", [b.field("id")]),
+      b.inlineFragment("Organization", [b.field("id")]),
+      b.inlineFragment("Bot", [b.field("id")]),
+    ]),
+  ];
+  return body;
+}