diff --git a/lib/coalesce.js b/lib/coalesce.js
new file mode 100644
index 0000000000..4875b409c7
--- /dev/null
+++ b/lib/coalesce.js
@@ -0,0 +1,5 @@
+'use strict'
+
+module.exports = function coalesce(...candidates) {
+  return candidates.find(c => c !== undefined && c !== null)
+}
diff --git a/lib/coalesce.spec.js b/lib/coalesce.spec.js
new file mode 100644
index 0000000000..ed596d4276
--- /dev/null
+++ b/lib/coalesce.spec.js
@@ -0,0 +1,23 @@
+'use strict'
+
+const { test, given } = require('sazerac')
+const coalesce = require('./coalesce')
+
+// Sticking with our one-line spread implementation, and defaulting to
+// `undefined` instead of `null`, though h/t to
+// https://github.com/royriojas/coalescy for these tests!
+
+describe('coalesce', function() {
+  test(coalesce, function() {
+    given().expect(undefined)
+    given(null, []).expect([])
+    given(null, [], {}).expect([])
+    given(null, undefined, 0, {}).expect(0)
+
+    const a = null,
+      c = 0,
+      d = 1
+    let b
+    given(a, b, c, d).expect(0)
+  })
+})
diff --git a/lib/request-handler.js b/lib/request-handler.js
index 7fc717b278..e9938da800 100644
--- a/lib/request-handler.js
+++ b/lib/request-handler.js
@@ -11,6 +11,7 @@ const analytics = require('./analytics')
 const { makeSend } = require('./result-sender')
 const queryString = require('query-string')
 const { Inaccessible } = require('../services/errors')
+const { setCacheHeaders } = require('../services/cache-headers')
 
 // We avoid calling the vendor's server for computation of the information in a
 // number of badges.
@@ -57,23 +58,6 @@ function flattenQueryParams(queryParams) {
   return Array.from(union).sort()
 }
 
-function getBadgeMaxAge(handlerOptions, queryParams) {
-  let maxAge = isInt(process.env.BADGE_MAX_AGE_SECONDS)
-    ? parseInt(process.env.BADGE_MAX_AGE_SECONDS)
-    : 120
-  if (handlerOptions.cacheLength) {
-    // If we've set a more specific cache length for this badge (or category),
-    // use that instead of env.BADGE_MAX_AGE_SECONDS.
-    maxAge = handlerOptions.cacheLength
-  }
-  if (isInt(queryParams.maxAge) && parseInt(queryParams.maxAge) > maxAge) {
-    // Only allow queryParams.maxAge to override the default if it is greater
-    // than the default.
-    maxAge = parseInt(queryParams.maxAge)
-  }
-  return maxAge
-}
-
 // handlerOptions can contain:
 // - handler: The service's request handler function
 // - queryParams: An array of the field names of any custom query parameters
@@ -89,31 +73,23 @@ function getBadgeMaxAge(handlerOptions, queryParams) {
 // (undesirable and hard to debug).
 //
 // Pass just the handler function as shorthand.
-function handleRequest(handlerOptions) {
+function handleRequest(cacheHeaderConfig, handlerOptions) {
   if (typeof handlerOptions === 'function') {
     handlerOptions = { handler: handlerOptions }
   }
 
   const allowedKeys = flattenQueryParams(handlerOptions.queryParams)
+  const { cacheLength: serviceCacheLengthSeconds } = handlerOptions
 
   return (queryParams, match, end, ask) => {
     const reqTime = new Date()
 
-    const maxAge = getBadgeMaxAge(handlerOptions, queryParams)
-    // send both Cache-Control max-age and Expires
-    // in case the client implements HTTP/1.0 but not HTTP/1.1
-    if (maxAge === 0) {
-      ask.res.setHeader('Cache-Control', 'no-cache, no-store, must-revalidate')
-      ask.res.setHeader('Expires', reqTime.toGMTString())
-    } else {
-      ask.res.setHeader('Cache-Control', `max-age=${maxAge}`)
-      ask.res.setHeader(
-        'Expires',
-        new Date(+reqTime + maxAge * 1000).toGMTString()
-      )
-    }
-
-    ask.res.setHeader('Date', reqTime.toGMTString())
+    setCacheHeaders({
+      cacheHeaderConfig,
+      serviceCacheLengthSeconds,
+      queryParams,
+      res: ask.res,
+    })
 
     analytics.noteRequest(queryParams, match)
 
@@ -269,14 +245,9 @@ function clearRequestCache() {
   requestCache.clear()
 }
 
-function isInt(number) {
-  return number !== undefined && /^[0-9]+$/.test(number)
-}
-
 module.exports = {
   handleRequest,
   clearRequestCache,
   // Expose for testing.
   _requestCache: requestCache,
-  getBadgeMaxAge,
 }
diff --git a/lib/request-handler.spec.js b/lib/request-handler.spec.js
index 26b46e3e52..cd269f77d7 100644
--- a/lib/request-handler.spec.js
+++ b/lib/request-handler.spec.js
@@ -1,7 +1,6 @@
 'use strict'
 
 const { expect } = require('chai')
-const { test, given } = require('sazerac')
 const fetch = require('node-fetch')
 const config = require('./test-config')
 const Camp = require('camp')
@@ -11,7 +10,6 @@ const {
   handleRequest,
   clearRequestCache,
   _requestCache,
-  getBadgeMaxAge,
 } = require('./request-handler')
 
 const baseUri = `http://127.0.0.1:${config.port}`
@@ -32,8 +30,6 @@ describe('The request handler', function() {
   before(analytics.load)
 
   let camp
-  const initialBadgeMaxAge = process.env.BADGE_MAX_AGE_SECONDS
-
   beforeEach(function(done) {
     camp = Camp.start({ port: config.port, hostname: '::' })
     camp.on('listening', () => done())
@@ -44,14 +40,15 @@ describe('The request handler', function() {
       camp.close(() => done())
       camp = null
     }
-    process.env.BADGE_MAX_AGE_SECONDS = initialBadgeMaxAge
   })
 
+  const standardCacheHeaders = { defaultCacheLengthSeconds: 120 }
+
   describe('the options object calling style', function() {
     beforeEach(function() {
       camp.route(
         /^\/testing\/([^/]+)\.(svg|png|gif|jpg|json)$/,
-        handleRequest({ handler: fakeHandler })
+        handleRequest(standardCacheHeaders, { handler: fakeHandler })
       )
     })
 
@@ -66,7 +63,7 @@ describe('The request handler', function() {
     beforeEach(function() {
       camp.route(
         /^\/testing\/([^/]+)\.(svg|png|gif|jpg|json)$/,
-        handleRequest(fakeHandler)
+        handleRequest(standardCacheHeaders, fakeHandler)
       )
     })
 
@@ -82,38 +79,50 @@ describe('The request handler', function() {
       let handlerCallCount
       beforeEach(function() {
         handlerCallCount = 0
+      })
+
+      function register({ cacheHeaderConfig }) {
         camp.route(
           /^\/testing\/([^/]+)\.(svg|png|gif|jpg|json)$/,
-          handleRequest((queryParams, match, sendBadge, request) => {
-            ++handlerCallCount
-            fakeHandler(queryParams, match, sendBadge, request)
-          })
+          handleRequest(
+            cacheHeaderConfig,
+            (queryParams, match, sendBadge, request) => {
+              ++handlerCallCount
+              fakeHandler(queryParams, match, sendBadge, request)
+            }
+          )
         )
+      }
+
+      context('With standard cache settings', function() {
+        beforeEach(function() {
+          register({ cacheHeaderConfig: standardCacheHeaders })
+        })
+
+        it('should cache identical requests', async function() {
+          await performTwoRequests('/testing/123.svg', '/testing/123.svg')
+          expect(handlerCallCount).to.equal(1)
+        })
+
+        it('should differentiate known query parameters', async function() {
+          await performTwoRequests(
+            '/testing/123.svg?label=foo',
+            '/testing/123.svg?label=bar'
+          )
+          expect(handlerCallCount).to.equal(2)
+        })
+
+        it('should ignore unknown query parameters', async function() {
+          await performTwoRequests(
+            '/testing/123.svg?foo=1',
+            '/testing/123.svg?foo=2'
+          )
+          expect(handlerCallCount).to.equal(1)
+        })
       })
 
-      it('should cache identical requests', async function() {
-        await performTwoRequests('/testing/123.svg', '/testing/123.svg')
-        expect(handlerCallCount).to.equal(1)
-      })
-
-      it('should differentiate known query parameters', async function() {
-        await performTwoRequests(
-          '/testing/123.svg?label=foo',
-          '/testing/123.svg?label=bar'
-        )
-        expect(handlerCallCount).to.equal(2)
-      })
-
-      it('should ignore unknown query parameters', async function() {
-        await performTwoRequests(
-          '/testing/123.svg?foo=1',
-          '/testing/123.svg?foo=2'
-        )
-        expect(handlerCallCount).to.equal(1)
-      })
-
-      it('should set the expires header to current time + BADGE_MAX_AGE_SECONDS', async function() {
-        process.env.BADGE_MAX_AGE_SECONDS = 900
+      it('should set the expires header to current time + defaultCacheLengthSeconds', async function() {
+        register({ cacheHeaderConfig: { defaultCacheLengthSeconds: 900 } })
         const res = await fetch(`${baseUri}/testing/123.json`)
         const expectedExpiry = new Date(
           +new Date(res.headers.get('date')) + 900000
@@ -123,7 +132,7 @@ describe('The request handler', function() {
       })
 
       it('should set the expires header to current time + maxAge', async function() {
-        process.env.BADGE_MAX_AGE_SECONDS = 0
+        register({ cacheHeaderConfig: { defaultCacheLengthSeconds: 0 } })
         const res = await fetch(`${baseUri}/testing/123.json?maxAge=3600`)
         const expectedExpiry = new Date(
           +new Date(res.headers.get('date')) + 3600000
@@ -132,8 +141,8 @@ describe('The request handler', function() {
         expect(res.headers.get('cache-control')).to.equal('max-age=3600')
       })
 
-      it('should ignore maxAge if maxAge < BADGE_MAX_AGE_SECONDS', async function() {
-        process.env.BADGE_MAX_AGE_SECONDS = 600
+      it('should ignore maxAge if maxAge < defaultCacheLengthSeconds', async function() {
+        register({ cacheHeaderConfig: { defaultCacheLengthSeconds: 600 } })
         const res = await fetch(`${baseUri}/testing/123.json?maxAge=300`)
         const expectedExpiry = new Date(
           +new Date(res.headers.get('date')) + 600000
@@ -143,7 +152,7 @@ describe('The request handler', function() {
       })
 
       it('should set Cache-Control: no-cache, no-store, must-revalidate if maxAge=0', async function() {
-        process.env.BADGE_MAX_AGE_SECONDS = 0
+        register({ cacheHeaderConfig: { defaultCacheLengthSeconds: 0 } })
         const res = await fetch(`${baseUri}/testing/123.json`)
         expect(res.headers.get('expires')).to.equal(res.headers.get('date'))
         expect(res.headers.get('cache-control')).to.equal(
@@ -151,17 +160,10 @@ describe('The request handler', function() {
         )
       })
 
-      it('should set the expires header to current time + 120 if BADGE_MAX_AGE_SECONDS not set', async function() {
-        delete process.env.BADGE_MAX_AGE_SECONDS
-        const res = await fetch(`${baseUri}/testing/123.json`)
-        const expectedExpiry = new Date(
-          +new Date(res.headers.get('date')) + 120000
-        ).toGMTString()
-        expect(res.headers.get('expires')).to.equal(expectedExpiry)
-        expect(res.headers.get('cache-control')).to.equal('max-age=120')
-      })
-
       describe('the cache key', function() {
+        beforeEach(function() {
+          register({ cacheHeaderConfig: standardCacheHeaders })
+        })
         const expectedCacheKey = '/testing/123.json?colorB=123&label=foo'
         it('should match expected and use canonical order - 1', async function() {
           const res = await fetch(
@@ -186,7 +188,7 @@ describe('The request handler', function() {
         handlerCallCount = 0
         camp.route(
           /^\/testing\/([^/]+)\.(svg|png|gif|jpg|json)$/,
-          handleRequest({
+          handleRequest(standardCacheHeaders, {
             queryParams: ['foo'],
             handler: (queryParams, match, sendBadge, request) => {
               ++handlerCallCount
@@ -205,14 +207,4 @@ describe('The request handler', function() {
       })
     })
   })
-
-  describe('getBadgeMaxAge function', function() {
-    process.env.BADGE_MAX_AGE_SECONDS = 120
-    test(getBadgeMaxAge, () => {
-      given({}, {}).expect(120)
-      given({ cacheLength: 900 }, {}).expect(900)
-      given({ cacheLength: 900 }, { maxAge: 1000 }).expect(1000)
-      given({ cacheLength: 900 }, { maxAge: 400 }).expect(900)
-    })
-  })
 })
diff --git a/lib/server-config.js b/lib/server-config.js
index 01832d822c..3861158f79 100644
--- a/lib/server-config.js
+++ b/lib/server-config.js
@@ -63,7 +63,8 @@ const config = {
       baseUri: process.env.GITHUB_URL || 'https://api.github.com',
       debug: {
         enabled: envFlag(process.env.GITHUB_DEBUG_ENABLED, false),
-        intervalSeconds: process.env.GITHUB_DEBUG_INTERVAL_SECONDS || 300,
+        intervalSeconds:
+          parseInt(process.env.GITHUB_DEBUG_INTERVAL_SECONDS) || 300,
       },
     },
     trace: envFlag(process.env.TRACE_SERVICES),
@@ -71,6 +72,10 @@ const config = {
   profiling: {
     makeBadge: envFlag(process.env.PROFILE_MAKE_BADGE),
   },
+  cacheHeaders: {
+    defaultCacheLengthSeconds:
+      parseInt(process.env.BADGE_MAX_AGE_SECONDS) || 120,
+  },
   rateLimit: envFlag(process.env.RATE_LIMIT, true),
   handleInternalErrors: envFlag(process.env.HANDLE_INTERNAL_ERRORS, true),
 }
diff --git a/package-lock.json b/package-lock.json
index a25e2a2148..d69417c7a8 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1423,8 +1423,7 @@
     "acorn": {
       "version": "2.7.0",
       "resolved": "https://registry.npmjs.org/acorn/-/acorn-2.7.0.tgz",
-      "integrity": "sha1-q259nYhqrKiwhbwzEreaGYQz8Oc=",
-      "optional": true
+      "integrity": "sha1-q259nYhqrKiwhbwzEreaGYQz8Oc="
     },
     "acorn-dynamic-import": {
       "version": "2.0.2",
@@ -1717,7 +1716,7 @@
         },
         "util": {
           "version": "0.10.3",
-          "resolved": "https://registry.npmjs.org/util/-/util-0.10.3.tgz",
+          "resolved": "http://registry.npmjs.org/util/-/util-0.10.3.tgz",
           "integrity": "sha1-evsa/lCAUkZInj23/g7TeTNqwPk=",
           "dev": true,
           "requires": {
@@ -2422,6 +2421,15 @@
         }
       }
     },
+    "chai-datetime": {
+      "version": "1.5.0",
+      "resolved": "https://registry.npmjs.org/chai-datetime/-/chai-datetime-1.5.0.tgz",
+      "integrity": "sha1-N0LxiwJMdbdqK37uKRZiMkRnWWw=",
+      "dev": true,
+      "requires": {
+        "chai": ">1.9.0"
+      }
+    },
     "chai-string": {
       "version": "1.5.0",
       "resolved": "https://registry.npmjs.org/chai-string/-/chai-string-1.5.0.tgz",
@@ -3458,8 +3466,7 @@
     "cssom": {
       "version": "0.3.2",
       "resolved": "https://registry.npmjs.org/cssom/-/cssom-0.3.2.tgz",
-      "integrity": "sha1-uANhcMefB6kP8vFuIihAJ6JDhIs=",
-      "optional": true
+      "integrity": "sha1-uANhcMefB6kP8vFuIihAJ6JDhIs="
     },
     "cssstyle": {
       "version": "0.2.37",
@@ -3894,7 +3901,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "dev": true,
           "requires": {
@@ -5258,7 +5265,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "dev": true,
           "requires": {
@@ -5405,7 +5412,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "dev": true,
           "requires": {
@@ -5481,8 +5488,7 @@
         "ansi-regex": {
           "version": "2.1.1",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "aproba": {
           "version": "1.2.0",
@@ -5503,14 +5509,12 @@
         "balanced-match": {
           "version": "1.0.0",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "brace-expansion": {
           "version": "1.1.11",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "balanced-match": "^1.0.0",
             "concat-map": "0.0.1"
@@ -5525,20 +5529,17 @@
         "code-point-at": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "concat-map": {
           "version": "0.0.1",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "console-control-strings": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "core-util-is": {
           "version": "1.0.2",
@@ -5655,8 +5656,7 @@
         "inherits": {
           "version": "2.0.3",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "ini": {
           "version": "1.3.5",
@@ -5668,7 +5668,6 @@
           "version": "1.0.0",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "number-is-nan": "^1.0.0"
           }
@@ -5683,7 +5682,6 @@
           "version": "3.0.4",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "brace-expansion": "^1.1.7"
           }
@@ -5691,14 +5689,12 @@
         "minimist": {
           "version": "0.0.8",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "minipass": {
           "version": "2.2.4",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "safe-buffer": "^5.1.1",
             "yallist": "^3.0.0"
@@ -5717,7 +5713,6 @@
           "version": "0.5.1",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "minimist": "0.0.8"
           }
@@ -5798,8 +5793,7 @@
         "number-is-nan": {
           "version": "1.0.1",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "object-assign": {
           "version": "4.1.1",
@@ -5811,7 +5805,6 @@
           "version": "1.4.0",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "wrappy": "1"
           }
@@ -5897,8 +5890,7 @@
         "safe-buffer": {
           "version": "5.1.1",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "safer-buffer": {
           "version": "2.1.2",
@@ -5934,7 +5926,6 @@
           "version": "1.0.2",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "code-point-at": "^1.0.0",
             "is-fullwidth-code-point": "^1.0.0",
@@ -5954,7 +5945,6 @@
           "version": "3.0.1",
           "bundled": true,
           "dev": true,
-          "optional": true,
           "requires": {
             "ansi-regex": "^2.0.0"
           }
@@ -5998,14 +5988,12 @@
         "wrappy": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "yallist": {
           "version": "3.0.2",
           "bundled": true,
-          "dev": true,
-          "optional": true
+          "dev": true
         }
       }
     },
@@ -6497,7 +6485,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "requires": {
             "core-util-is": "~1.0.0",
@@ -7984,7 +7972,7 @@
       "dependencies": {
         "chalk": {
           "version": "1.1.3",
-          "resolved": "https://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
           "integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
           "dev": true,
           "requires": {
@@ -8443,6 +8431,12 @@
       "resolved": "https://registry.npmjs.org/mdn-data/-/mdn-data-1.1.4.tgz",
       "integrity": "sha512-FSYbp3lyKjyj3E7fMl6rYvUdX0FBXaluGqlFoYESWQlyUTq8R+wp0rkFxoYFqZlHCvsUXGjyJmLQSnXToYhOSA=="
     },
+    "media-typer": {
+      "version": "0.3.0",
+      "resolved": "http://registry.npmjs.org/media-typer/-/media-typer-0.3.0.tgz",
+      "integrity": "sha1-hxDXrwqmJvj/+hzgAWhUUmMlV0g=",
+      "dev": true
+    },
     "mem": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/mem/-/mem-1.1.0.tgz",
@@ -8482,7 +8476,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "dev": true,
           "requires": {
@@ -8607,6 +8601,18 @@
         }
       }
     },
+    "merge-descriptors": {
+      "version": "1.0.1",
+      "resolved": "https://registry.npmjs.org/merge-descriptors/-/merge-descriptors-1.0.1.tgz",
+      "integrity": "sha1-sAqqVW3YtEVoFQ7J0blT8/kMu2E=",
+      "dev": true
+    },
+    "methods": {
+      "version": "1.1.2",
+      "resolved": "https://registry.npmjs.org/methods/-/methods-1.1.2.tgz",
+      "integrity": "sha1-VSmk1nZUE07cxSZmVoNbD4Ua/O4=",
+      "dev": true
+    },
     "micromatch": {
       "version": "3.1.10",
       "resolved": "https://registry.npmjs.org/micromatch/-/micromatch-3.1.10.tgz",
@@ -8983,6 +8989,12 @@
       "integrity": "sha512-MFh0d/Wa7vkKO3Y3LlacqAEeHK0mckVqzDieUKTT+KGxi+zIpeVsFxymkIiRpbpDziHc290Xr9A1O4Om7otoRA==",
       "dev": true
     },
+    "net": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/net/-/net-1.0.2.tgz",
+      "integrity": "sha1-0XV+yaf7I3HYPPR1XOPifhCCk4g=",
+      "dev": true
+    },
     "next": {
       "version": "6.1.2",
       "resolved": "https://registry.npmjs.org/next/-/next-6.1.2.tgz",
@@ -10139,7 +10151,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "dev": true,
           "requires": {
@@ -10163,6 +10175,24 @@
         }
       }
     },
+    "node-mocks-http": {
+      "version": "1.7.3",
+      "resolved": "https://registry.npmjs.org/node-mocks-http/-/node-mocks-http-1.7.3.tgz",
+      "integrity": "sha512-wayzLNhEroH3lJj113pFKQ1cd1GKG1mXoZR1HcKp/o9a9lTGGgVY/hYeLajiIFr/z4tXFKOdfJickqqihBtn9g==",
+      "dev": true,
+      "requires": {
+        "accepts": "^1.3.5",
+        "depd": "^1.1.0",
+        "fresh": "^0.5.2",
+        "merge-descriptors": "^1.0.1",
+        "methods": "^1.1.2",
+        "mime": "^1.3.4",
+        "net": "^1.0.2",
+        "parseurl": "^1.3.1",
+        "range-parser": "^1.2.0",
+        "type-is": "^1.6.16"
+      }
+    },
     "node-modules-regexp": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/node-modules-regexp/-/node-modules-regexp-1.0.0.tgz",
@@ -10333,7 +10363,6 @@
           "resolved": false,
           "integrity": "sha1-DNkKVhCT810KmSVsIrcGlDP60Rc=",
           "dev": true,
-          "optional": true,
           "requires": {
             "kind-of": "^3.0.2",
             "longest": "^1.0.1",
@@ -10703,8 +10732,7 @@
           "version": "1.1.6",
           "resolved": false,
           "integrity": "sha512-NcdALwpXkTm5Zvvbk7owOUSvVvBKDgKP5/ewfXEznmQFfs4ZRmanOeKBTjRVjka3QFoN6XJ+9F3USqfHqTaU5w==",
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "is-builtin-module": {
           "version": "1.0.0",
@@ -10800,7 +10828,6 @@
           "resolved": false,
           "integrity": "sha1-MeohpzS6ubuw8yRm2JOupR5KPGQ=",
           "dev": true,
-          "optional": true,
           "requires": {
             "is-buffer": "^1.1.5"
           }
@@ -10853,8 +10880,7 @@
           "version": "1.0.1",
           "resolved": false,
           "integrity": "sha1-MKCy2jj3N3DoKUoNIuZiXtd9AJc=",
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "lru-cache": {
           "version": "4.1.3",
@@ -11157,8 +11183,7 @@
           "version": "1.6.1",
           "resolved": false,
           "integrity": "sha1-jcrkcOHIirwtYA//Sndihtp15jc=",
-          "dev": true,
-          "optional": true
+          "dev": true
         },
         "require-directory": {
           "version": "2.1.1",
@@ -11921,7 +11946,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "dev": true,
           "requires": {
@@ -12064,6 +12089,12 @@
         "better-assert": "~1.0.0"
       }
     },
+    "parseurl": {
+      "version": "1.3.2",
+      "resolved": "https://registry.npmjs.org/parseurl/-/parseurl-1.3.2.tgz",
+      "integrity": "sha1-/CidTtiZMRlGDBViUyYs3I3mW/M=",
+      "dev": true
+    },
     "pascalcase": {
       "version": "0.1.1",
       "resolved": "https://registry.npmjs.org/pascalcase/-/pascalcase-0.1.1.tgz",
@@ -12821,7 +12852,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "dev": true,
           "requires": {
@@ -14024,7 +14055,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "requires": {
             "core-util-is": "~1.0.0",
@@ -14236,7 +14267,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "dev": true,
           "requires": {
@@ -14297,7 +14328,7 @@
         },
         "readable-stream": {
           "version": "2.3.6",
-          "resolved": "https://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
+          "resolved": "http://registry.npmjs.org/readable-stream/-/readable-stream-2.3.6.tgz",
           "integrity": "sha512-tQtKA9WIAhBF3+VLAseyMqZeBjW0AHJoxOtYqSUZNJxauErmLbVm2FW1y+J/YA9dUrAC39ITejlZWhVIwawkKw==",
           "dev": true,
           "requires": {
@@ -14879,6 +14910,33 @@
       "resolved": "https://registry.npmjs.org/type-detect/-/type-detect-4.0.3.tgz",
       "integrity": "sha1-Dj8mcLRAmbC0bChNE2p+9Jx0wuo="
     },
+    "type-is": {
+      "version": "1.6.16",
+      "resolved": "https://registry.npmjs.org/type-is/-/type-is-1.6.16.tgz",
+      "integrity": "sha512-HRkVv/5qY2G6I8iab9cI7v1bOIdhm94dVjQCPFElW9W+3GeDOSHmy2EBYe4VTApuzolPcmgFTN3ftVJRKR2J9Q==",
+      "dev": true,
+      "requires": {
+        "media-typer": "0.3.0",
+        "mime-types": "~2.1.18"
+      },
+      "dependencies": {
+        "mime-db": {
+          "version": "1.37.0",
+          "resolved": "https://registry.npmjs.org/mime-db/-/mime-db-1.37.0.tgz",
+          "integrity": "sha512-R3C4db6bgQhlIhPU48fUtdVmKnflq+hRdad7IyKhtFj06VPNVdk2RhiYL3UjQIlso8L+YxAtFkobT0VK+S/ybg==",
+          "dev": true
+        },
+        "mime-types": {
+          "version": "2.1.21",
+          "resolved": "https://registry.npmjs.org/mime-types/-/mime-types-2.1.21.tgz",
+          "integrity": "sha512-3iL6DbwpyLzjR3xHSFNFeb9Nz/M8WDkX33t1GFQnFOllWk8pOrh/LSrB5OXlnlW5P9LH73X6loW/eogc+F5lJg==",
+          "dev": true,
+          "requires": {
+            "mime-db": "~1.37.0"
+          }
+        }
+      }
+    },
     "typedarray": {
       "version": "0.0.6",
       "resolved": "https://registry.npmjs.org/typedarray/-/typedarray-0.0.6.tgz",
diff --git a/package.json b/package.json
index 40031e7a63..3bd2f7d08f 100644
--- a/package.json
+++ b/package.json
@@ -114,6 +114,7 @@
     "babel-eslint": "^10.0.0",
     "caller": "^1.0.1",
     "chai": "^4.1.2",
+    "chai-datetime": "^1.5.0",
     "chai-string": "^1.4.0",
     "chainsmoker": "^0.1.0",
     "child-process-promise": "^2.2.1",
@@ -154,6 +155,7 @@
     "next": "^6.1.1",
     "nock": "^10.0.0",
     "node-fetch": "^2.3.0",
+    "node-mocks-http": "^1.7.3",
     "nyc": "^13.0.1",
     "opn-cli": "^4.0.0",
     "prettier": "1.15.3",
diff --git a/server.js b/server.js
index 132b7495d4..b554d25215 100644
--- a/server.js
+++ b/server.js
@@ -105,6 +105,7 @@ loadServiceClasses().forEach(serviceClass =>
     { camp, handleRequest: cache, githubApiProvider },
     {
       handleInternalErrors: config.handleInternalErrors,
+      cacheHeaders: config.cacheHeaders,
       profiling: config.profiling,
     }
   )
@@ -113,7 +114,7 @@ loadServiceClasses().forEach(serviceClass =>
 // User defined sources - JSON response
 camp.route(
   /^\/badge\/dynamic\/(json|xml|yaml)\.(svg|png|gif|jpg|json)$/,
-  cache({
+  cache(config.cacheHeaders, {
     queryParams: ['uri', 'url', 'query', 'prefix', 'suffix'],
     handler: function(query, match, sendBadge, request) {
       const type = match[1]
@@ -226,22 +227,6 @@ camp.route(
   })
 )
 
-// Production cache debugging.
-let bitFlip = false
-camp.route(/^\/flip\.svg$/, (data, match, end, ask) => {
-  const cacheSecs = 60
-  ask.res.setHeader('Cache-Control', `max-age=${cacheSecs}`)
-  const reqTime = new Date()
-  const date = new Date(+reqTime + cacheSecs * 1000).toGMTString()
-  ask.res.setHeader('Expires', date)
-  const badgeData = getBadgeData('flip', data)
-  bitFlip = !bitFlip
-  badgeData.text[1] = bitFlip ? 'on' : 'off'
-  badgeData.colorscheme = bitFlip ? 'brightgreen' : 'red'
-  const svg = makeBadge(badgeData)
-  makeSend('svg', ask.res, end)(svg)
-})
-
 // Any badge, old version. This route must be registered last.
 camp.route(/^\/([^/]+)\/(.+).png$/, (queryParams, match, end, ask) => {
   const [, label, message] = match
diff --git a/server.spec.js b/server.spec.js
index 781e8e5011..9320288b3a 100644
--- a/server.spec.js
+++ b/server.spec.js
@@ -2,6 +2,7 @@
 
 const { expect } = require('chai')
 const config = require('./lib/test-config')
+const serverConfig = require('./lib/server-config')
 const fetch = require('node-fetch')
 const fs = require('fs')
 const isPng = require('is-png')
@@ -33,7 +34,7 @@ describe('The server', function() {
     //   at _combinedTickCallback (internal/process/next_tick.js:141:11)
     //   at process._tickDomainCallback (internal/process/next_tick.js:218:9)
     loadServiceClasses().forEach(serviceClass =>
-      serviceClass.register({ camp: dummyCamp, handleRequest }, {})
+      serviceClass.register({ camp: dummyCamp, handleRequest }, serverConfig)
     )
     dummyCamp.close()
     dummyCamp = undefined
@@ -50,7 +51,7 @@ describe('The server', function() {
   const baseUri = `http://127.0.0.1:${config.port}`
 
   let server
-  before('Start running the server', function() {
+  before('Start the server', function() {
     this.timeout(5000)
     server = serverHelpers.start()
   })
diff --git a/services/base-json.spec.js b/services/base-json.spec.js
index ae47d85361..bc8ba92a10 100644
--- a/services/base-json.spec.js
+++ b/services/base-json.spec.js
@@ -32,7 +32,7 @@ class DummyJsonService extends BaseJsonService {
 
 describe('BaseJsonService', function() {
   describe('Making requests', function() {
-    let sendAndCacheRequest, serviceInstance
+    let sendAndCacheRequest
     beforeEach(function() {
       sendAndCacheRequest = sinon.stub().returns(
         Promise.resolve({
@@ -40,25 +40,22 @@ describe('BaseJsonService', function() {
           res: { statusCode: 200 },
         })
       )
-      serviceInstance = new DummyJsonService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
     })
 
     it('invokes _sendAndCacheRequest', async function() {
-      await serviceInstance.invokeHandler({}, {})
+      await DummyJsonService.invoke(
+        { sendAndCacheRequest },
+        { handleInternalErrors: false }
+      )
 
       expect(sendAndCacheRequest).to.have.been.calledOnceWith(
         'http://example.com/foo.json',
-        {
-          headers: { Accept: 'application/json' },
-        }
+        { headers: { Accept: 'application/json' } }
       )
     })
 
     it('forwards options to _sendAndCacheRequest', async function() {
-      Object.assign(serviceInstance, {
+      class WithOptions extends DummyJsonService {
         async handle() {
           const { value } = await this._requestJson({
             schema: dummySchema,
@@ -66,10 +63,13 @@ describe('BaseJsonService', function() {
             options: { method: 'POST', qs: { queryParam: 123 } },
           })
           return { message: value }
-        },
-      })
+        }
+      }
 
-      await serviceInstance.invokeHandler({}, {})
+      await WithOptions.invoke(
+        { sendAndCacheRequest },
+        { handleInternalErrors: false }
+      )
 
       expect(sendAndCacheRequest).to.have.been.calledOnceWith(
         'http://example.com/foo.json',
@@ -88,12 +88,12 @@ describe('BaseJsonService', function() {
         buffer: '{"requiredString": "some-string"}',
         res: { statusCode: 200 },
       })
-      const serviceInstance = new DummyJsonService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
-      const serviceData = await serviceInstance.invokeHandler({}, {})
-      expect(serviceData).to.deep.equal({
+      expect(
+        await DummyJsonService.invoke(
+          { sendAndCacheRequest },
+          { handleInternalErrors: false }
+        )
+      ).to.deep.equal({
         message: 'some-string',
       })
     })
@@ -103,12 +103,12 @@ describe('BaseJsonService', function() {
         buffer: '{"unexpectedKey": "some-string"}',
         res: { statusCode: 200 },
       })
-      const serviceInstance = new DummyJsonService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
-      const serviceData = await serviceInstance.invokeHandler({}, {})
-      expect(serviceData).to.deep.equal({
+      expect(
+        await DummyJsonService.invoke(
+          { sendAndCacheRequest },
+          { handleInternalErrors: false }
+        )
+      ).to.deep.equal({
         color: 'lightgray',
         message: 'invalid response data',
       })
@@ -119,12 +119,12 @@ describe('BaseJsonService', function() {
         buffer: 'not json',
         res: { statusCode: 200 },
       })
-      const serviceInstance = new DummyJsonService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
-      const serviceData = await serviceInstance.invokeHandler({}, {})
-      expect(serviceData).to.deep.equal({
+      expect(
+        await DummyJsonService.invoke(
+          { sendAndCacheRequest },
+          { handleInternalErrors: false }
+        )
+      ).to.deep.equal({
         color: 'lightgray',
         message: 'unparseable json response',
       })
diff --git a/services/base-non-memory-caching.js b/services/base-non-memory-caching.js
new file mode 100644
index 0000000000..225983a2fb
--- /dev/null
+++ b/services/base-non-memory-caching.js
@@ -0,0 +1,55 @@
+'use strict'
+
+const makeBadge = require('../gh-badges/lib/make-badge')
+const { makeSend } = require('../lib/result-sender')
+const BaseService = require('./base')
+const { setCacheHeaders } = require('./cache-headers')
+
+// Badges are subject to two independent types of caching: in-memory and
+// downstream.
+//
+// Services deriving from `NonMemoryCachingBaseService` are not cached in
+// memory on the server. This means that each request that hits the server
+// triggers another call to the handler. When using badges for server
+// diagnostics, that's useful!
+//
+// In constrast, The `handle()` function of most other `BaseService`
+// subclasses is wrapped in onboard, in-memory caching. See `lib /request-
+// handler.js` and `BaseService.prototype.register()`.
+//
+// All services, including those extending NonMemoryCachingBaseServices, may
+// be cached _downstream_. This is governed by cache headers, which are
+// configured by the service, the user's request, and the server's default
+// cache length.
+module.exports = class NonMemoryCachingBaseService extends BaseService {
+  static register({ camp }, serviceConfig) {
+    const { cacheHeaders: cacheHeaderConfig } = serviceConfig
+    const { _cacheLength: serviceCacheLengthSeconds } = this
+
+    camp.route(this._regex, async (queryParams, match, end, ask) => {
+      const namedParams = this._namedParamsForMatch(match)
+      const serviceData = await this.invoke(
+        {},
+        serviceConfig,
+        namedParams,
+        queryParams
+      )
+
+      const badgeData = this._makeBadgeData(queryParams, serviceData)
+      // The final capture group is the extension.
+      const format = match.slice(-1)[0]
+      badgeData.format = format
+
+      const svg = makeBadge(badgeData)
+
+      setCacheHeaders({
+        cacheHeaderConfig,
+        serviceCacheLengthSeconds,
+        queryParams,
+        res: ask.res,
+      })
+
+      makeSend(format, ask.res, end)(svg)
+    })
+  }
+}
diff --git a/services/base-static.js b/services/base-static.js
index cbaac7ea03..6d146ce21e 100644
--- a/services/base-static.js
+++ b/services/base-static.js
@@ -4,53 +4,49 @@ const makeBadge = require('../gh-badges/lib/make-badge')
 const { makeSend } = require('../lib/result-sender')
 const analytics = require('../lib/analytics')
 const BaseService = require('./base')
-
-const serverStartTime = new Date(new Date().toGMTString())
+const {
+  serverHasBeenUpSinceResourceCached,
+  setCacheHeadersForStaticResource,
+} = require('./cache-headers')
 
 module.exports = class BaseStaticService extends BaseService {
-  // Note: Since this is a static service, it is not `async`.
-  handle(namedParams, queryParams) {
-    throw new Error(`Handler not implemented for ${this.constructor.name}`)
-  }
-
   static register({ camp }, serviceConfig) {
-    camp.route(this._regex, (queryParams, match, end, ask) => {
+    const {
+      profiling: { makeBadge: shouldProfileMakeBadge },
+    } = serviceConfig
+
+    camp.route(this._regex, async (queryParams, match, end, ask) => {
       analytics.noteRequest(queryParams, match)
 
-      if (+new Date(ask.req.headers['if-modified-since']) >= +serverStartTime) {
+      if (serverHasBeenUpSinceResourceCached(ask.req)) {
         // Send Not Modified.
         ask.res.statusCode = 304
         ask.res.end()
         return
       }
 
-      const serviceInstance = new this({}, serviceConfig)
       const namedParams = this._namedParamsForMatch(match)
-      let serviceData
-      try {
-        // Note: no `await`.
-        serviceData = serviceInstance.handle(namedParams, queryParams)
-      } catch (error) {
-        serviceData = serviceInstance._handleError(error)
-      }
+      const serviceData = await this.invoke(
+        {},
+        serviceConfig,
+        namedParams,
+        queryParams
+      )
 
       const badgeData = this._makeBadgeData(queryParams, serviceData)
-
       // The final capture group is the extension.
       const format = match.slice(-1)[0]
       badgeData.format = format
 
-      if (serviceConfig.profiling.makeBadge) {
+      if (shouldProfileMakeBadge) {
         console.time('makeBadge total')
       }
       const svg = makeBadge(badgeData)
-      if (serviceConfig.profiling.makeBadge) {
+      if (shouldProfileMakeBadge) {
         console.timeEnd('makeBadge total')
       }
 
-      const cacheDuration = 3600 * 24 * 1 // 1 day.
-      ask.res.setHeader('Cache-Control', `max-age=${cacheDuration}`)
-      ask.res.setHeader('Last-Modified', serverStartTime.toGMTString())
+      setCacheHeadersForStaticResource(ask.res)
 
       makeSend(format, ask.res, end)(svg)
     })
diff --git a/services/base-svg-scraping.spec.js b/services/base-svg-scraping.spec.js
index 550f8b1c0e..cfa37b2bce 100644
--- a/services/base-svg-scraping.spec.js
+++ b/services/base-svg-scraping.spec.js
@@ -53,7 +53,7 @@ describe('BaseSvgScrapingService', function() {
   })
 
   describe('Making requests', function() {
-    let sendAndCacheRequest, serviceInstance
+    let sendAndCacheRequest
     beforeEach(function() {
       sendAndCacheRequest = sinon.stub().returns(
         Promise.resolve({
@@ -61,25 +61,22 @@ describe('BaseSvgScrapingService', function() {
           res: { statusCode: 200 },
         })
       )
-      serviceInstance = new DummySvgScrapingService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
     })
 
     it('invokes _sendAndCacheRequest with the expected header', async function() {
-      await serviceInstance.invokeHandler({}, {})
+      await DummySvgScrapingService.invoke(
+        { sendAndCacheRequest },
+        { handleInternalErrors: false }
+      )
 
       expect(sendAndCacheRequest).to.have.been.calledOnceWith(
         'http://example.com/foo.svg',
-        {
-          headers: { Accept: 'image/svg+xml' },
-        }
+        { headers: { Accept: 'image/svg+xml' } }
       )
     })
 
     it('forwards options to _sendAndCacheRequest', async function() {
-      Object.assign(serviceInstance, {
+      class WithCustomOptions extends DummySvgScrapingService {
         async handle() {
           const { value } = await this._requestSvg({
             schema,
@@ -90,10 +87,13 @@ describe('BaseSvgScrapingService', function() {
             },
           })
           return { message: value }
-        },
-      })
+        }
+      }
 
-      await serviceInstance.invokeHandler({}, {})
+      await WithCustomOptions.invoke(
+        { sendAndCacheRequest },
+        { handleInternalErrors: false }
+      )
 
       expect(sendAndCacheRequest).to.have.been.calledOnceWith(
         'http://example.com/foo.svg',
@@ -112,36 +112,36 @@ describe('BaseSvgScrapingService', function() {
         buffer: exampleSvg,
         res: { statusCode: 200 },
       })
-      const serviceInstance = new DummySvgScrapingService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
-      const serviceData = await serviceInstance.invokeHandler({}, {})
-      expect(serviceData).to.deep.equal({
+      expect(
+        await DummySvgScrapingService.invoke(
+          { sendAndCacheRequest },
+          { handleInternalErrors: false }
+        )
+      ).to.deep.equal({
         message: exampleMessage,
       })
     })
 
     it('allows overriding the valueMatcher', async function() {
-      const sendAndCacheRequest = async () => ({
-        buffer: '<desc>a different message</desc>',
-        res: { statusCode: 200 },
-      })
-      const serviceInstance = new DummySvgScrapingService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
-      Object.assign(serviceInstance, {
+      class WithValueMatcher extends BaseSvgScrapingService {
         async handle() {
           return this._requestSvg({
             schema,
             valueMatcher: />([^<>]+)<\/desc>/,
             url: 'http://example.com/foo.svg',
           })
-        },
+        }
+      }
+      const sendAndCacheRequest = async () => ({
+        buffer: '<desc>a different message</desc>',
+        res: { statusCode: 200 },
       })
-      const serviceData = await serviceInstance.invokeHandler({}, {})
-      expect(serviceData).to.deep.equal({
+      expect(
+        await WithValueMatcher.invoke(
+          { sendAndCacheRequest },
+          { handleInternalErrors: false }
+        )
+      ).to.deep.equal({
         message: 'a different message',
       })
     })
@@ -151,12 +151,12 @@ describe('BaseSvgScrapingService', function() {
         buffer: 'not svg yo',
         res: { statusCode: 200 },
       })
-      const serviceInstance = new DummySvgScrapingService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
-      const serviceData = await serviceInstance.invokeHandler({}, {})
-      expect(serviceData).to.deep.equal({
+      expect(
+        await DummySvgScrapingService.invoke(
+          { sendAndCacheRequest },
+          { handleInternalErrors: false }
+        )
+      ).to.deep.equal({
         color: 'lightgray',
         message: 'unparseable svg response',
       })
diff --git a/services/base-xml.spec.js b/services/base-xml.spec.js
index 801cb5885c..5c3ad696ab 100644
--- a/services/base-xml.spec.js
+++ b/services/base-xml.spec.js
@@ -32,7 +32,7 @@ class DummyXmlService extends BaseXmlService {
 
 describe('BaseXmlService', function() {
   describe('Making requests', function() {
-    let sendAndCacheRequest, serviceInstance
+    let sendAndCacheRequest
     beforeEach(function() {
       sendAndCacheRequest = sinon.stub().returns(
         Promise.resolve({
@@ -40,25 +40,22 @@ describe('BaseXmlService', function() {
           res: { statusCode: 200 },
         })
       )
-      serviceInstance = new DummyXmlService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
     })
 
     it('invokes _sendAndCacheRequest', async function() {
-      await serviceInstance.invokeHandler({}, {})
+      await DummyXmlService.invoke(
+        { sendAndCacheRequest },
+        { handleInternalErrors: false }
+      )
 
       expect(sendAndCacheRequest).to.have.been.calledOnceWith(
         'http://example.com/foo.xml',
-        {
-          headers: { Accept: 'application/xml, text/xml' },
-        }
+        { headers: { Accept: 'application/xml, text/xml' } }
       )
     })
 
     it('forwards options to _sendAndCacheRequest', async function() {
-      Object.assign(serviceInstance, {
+      class WithCustomOptions extends BaseXmlService {
         async handle() {
           const { value } = await this._requestXml({
             schema: dummySchema,
@@ -66,10 +63,13 @@ describe('BaseXmlService', function() {
             options: { method: 'POST', qs: { queryParam: 123 } },
           })
           return { message: value }
-        },
-      })
+        }
+      }
 
-      await serviceInstance.invokeHandler({}, {})
+      await WithCustomOptions.invoke(
+        { sendAndCacheRequest },
+        { handleInternalErrors: false }
+      )
 
       expect(sendAndCacheRequest).to.have.been.calledOnceWith(
         'http://example.com/foo.xml',
@@ -88,12 +88,12 @@ describe('BaseXmlService', function() {
         buffer: '<requiredString>some-string</requiredString>',
         res: { statusCode: 200 },
       })
-      const serviceInstance = new DummyXmlService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
-      const serviceData = await serviceInstance.invokeHandler({}, {})
-      expect(serviceData).to.deep.equal({
+      expect(
+        await DummyXmlService.invoke(
+          { sendAndCacheRequest },
+          { handleInternalErrors: false }
+        )
+      ).to.deep.equal({
         message: 'some-string',
       })
     })
@@ -115,14 +115,12 @@ describe('BaseXmlService', function() {
           '<requiredString>some-string with trailing whitespace   </requiredString>',
         res: { statusCode: 200 },
       })
-      const serviceInstance = new DummyXmlServiceWithParserOption(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
-
-      const serviceData = await serviceInstance.invokeHandler({}, {})
-
-      expect(serviceData).to.deep.equal({
+      expect(
+        await DummyXmlServiceWithParserOption.invoke(
+          { sendAndCacheRequest },
+          { handleInternalErrors: false }
+        )
+      ).to.deep.equal({
         message: 'some-string with trailing whitespace   ',
       })
     })
@@ -132,12 +130,12 @@ describe('BaseXmlService', function() {
         buffer: '<unexpectedAttribute>some-string</unexpectedAttribute>',
         res: { statusCode: 200 },
       })
-      const serviceInstance = new DummyXmlService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
-      const serviceData = await serviceInstance.invokeHandler({}, {})
-      expect(serviceData).to.deep.equal({
+      expect(
+        await DummyXmlService.invoke(
+          { sendAndCacheRequest },
+          { handleInternalErrors: false }
+        )
+      ).to.deep.equal({
         color: 'lightgray',
         message: 'invalid response data',
       })
@@ -148,12 +146,12 @@ describe('BaseXmlService', function() {
         buffer: 'not xml',
         res: { statusCode: 200 },
       })
-      const serviceInstance = new DummyXmlService(
-        { sendAndCacheRequest },
-        { handleInternalErrors: false }
-      )
-      const serviceData = await serviceInstance.invokeHandler({}, {})
-      expect(serviceData).to.deep.equal({
+      expect(
+        await DummyXmlService.invoke(
+          { sendAndCacheRequest },
+          { handleInternalErrors: false }
+        )
+      ).to.deep.equal({
         color: 'lightgray',
         message: 'unparseable xml response',
       })
diff --git a/services/base.js b/services/base.js
index f1279c06b9..13b13ab117 100644
--- a/services/base.js
+++ b/services/base.js
@@ -11,6 +11,7 @@ const {
   InvalidParameter,
   Deprecated,
 } = require('./errors')
+const coalesce = require('../lib/coalesce')
 const validate = require('../lib/validate')
 const { checkErrorResponse } = require('../lib/error-helper')
 const {
@@ -23,10 +24,6 @@ const { staticBadgeUrl } = require('../lib/make-badge-url')
 const trace = require('./trace')
 const validateExample = require('./validate-example')
 
-function coalesce(...candidates) {
-  return candidates.find(c => c !== undefined)
-}
-
 class BaseService {
   constructor({ sendAndCacheRequest }, { handleInternalErrors }) {
     this._requestFetcher = sendAndCacheRequest
@@ -249,6 +246,7 @@ class BaseService {
       build: 30,
       license: 3600,
       version: 300,
+      debug: 60,
     }
     return cacheLengths[this.category]
   }
@@ -321,20 +319,28 @@ class BaseService {
     }
   }
 
-  async invokeHandler(namedParams, queryParams) {
-    trace.logTrace(
-      'inbound',
-      emojic.womanCook,
-      'Service class',
-      this.constructor.name
-    )
+  static async invoke(
+    context = {},
+    config = {},
+    namedParams = {},
+    queryParams = {}
+  ) {
+    trace.logTrace('inbound', emojic.womanCook, 'Service class', this.name)
     trace.logTrace('inbound', emojic.ticket, 'Named params', namedParams)
     trace.logTrace('inbound', emojic.crayon, 'Query params', queryParams)
+
+    const serviceInstance = new this(context, config)
+
+    let serviceData
     try {
-      return await this.handle(namedParams, queryParams)
+      serviceData = await serviceInstance.handle(namedParams, queryParams)
     } catch (error) {
-      return this._handleError(error)
+      serviceData = serviceInstance._handleError(error)
     }
+
+    trace.logTrace('outbound', emojic.shield, 'Service data', serviceData)
+
+    return serviceData
   }
 
   static _makeBadgeData(overrides, serviceData) {
@@ -385,27 +391,25 @@ class BaseService {
   }
 
   static register({ camp, handleRequest, githubApiProvider }, serviceConfig) {
+    const { cacheHeaders: cacheHeaderConfig } = serviceConfig
     camp.route(
       this._regex,
-      handleRequest({
+      handleRequest(cacheHeaderConfig, {
         queryParams: this.route.queryParams,
         handler: async (queryParams, match, sendBadge, request) => {
-          const serviceInstance = new this(
+          const namedParams = this._namedParamsForMatch(match)
+          const serviceData = await this.invoke(
             {
               sendAndCacheRequest: request.asPromise,
               sendAndCacheRequestWithCallbacks: request,
               githubApiProvider,
             },
-            serviceConfig
-          )
-          const namedParams = this._namedParamsForMatch(match)
-          const serviceData = await serviceInstance.invokeHandler(
+            serviceConfig,
             namedParams,
             queryParams
           )
-          trace.logTrace('outbound', emojic.shield, 'Service data', serviceData)
-          const badgeData = this._makeBadgeData(queryParams, serviceData)
 
+          const badgeData = this._makeBadgeData(queryParams, serviceData)
           // The final capture group is the extension.
           const format = match.slice(-1)[0]
           sendBadge(format, badgeData)
diff --git a/services/base.spec.js b/services/base.spec.js
index 3dbaf79835..34fdbca275 100644
--- a/services/base.spec.js
+++ b/services/base.spec.js
@@ -198,12 +198,14 @@ describe('BaseService', function() {
   })
 
   it('Invokes the handler as expected', async function() {
-    const serviceInstance = new DummyService({}, defaultConfig)
-    const serviceData = await serviceInstance.invokeHandler(
-      { namedParamA: 'bar.bar.bar' },
-      { queryParamA: '!' }
-    )
-    expect(serviceData).to.deep.equal({
+    expect(
+      await DummyService.invoke(
+        {},
+        defaultConfig,
+        { namedParamA: 'bar.bar.bar' },
+        { queryParamA: '!' }
+      )
+    ).to.deep.equal({
       message: 'Hello namedParamA: bar.bar.bar with queryParamA: !',
     })
   })
@@ -220,11 +222,10 @@ describe('BaseService', function() {
       sandbox.stub(trace, 'logTrace')
     })
     it('Invokes the logger as expected', async function() {
-      const serviceInstance = new DummyService({}, defaultConfig)
-      await serviceInstance.invokeHandler(
-        {
-          namedParamA: 'bar.bar.bar',
-        },
+      await DummyService.invoke(
+        {},
+        defaultConfig,
+        { namedParamA: 'bar.bar.bar' },
         { queryParamA: '!' }
       )
       expect(trace.logTrace).to.be.calledWithMatch(
@@ -237,9 +238,7 @@ describe('BaseService', function() {
         'inbound',
         sinon.match.string,
         'Named params',
-        {
-          namedParamA: 'bar.bar.bar',
-        }
+        { namedParamA: 'bar.bar.bar' }
       )
       expect(trace.logTrace).to.be.calledWith(
         'inbound',
@@ -252,17 +251,17 @@ describe('BaseService', function() {
 
   describe('Error handling', function() {
     it('Handles internal errors', async function() {
-      const serviceInstance = new DummyService(
-        {},
-        { handleInternalErrors: true }
-      )
-      serviceInstance.handle = () => {
-        throw Error("I've made a huge mistake")
+      class ThrowingService extends DummyService {
+        async handle() {
+          throw Error("I've made a huge mistake")
+        }
       }
       expect(
-        await serviceInstance.invokeHandler({
-          namedParamA: 'bar.bar.bar',
-        })
+        await ThrowingService.invoke(
+          {},
+          { handleInternalErrors: true },
+          { namedParamA: 'bar.bar.bar' }
+        )
       ).to.deep.equal({
         color: 'lightgray',
         label: 'shields',
@@ -271,19 +270,14 @@ describe('BaseService', function() {
     })
 
     describe('Handles known subtypes of ShieldsInternalError', function() {
-      let serviceInstance
-      beforeEach(function() {
-        serviceInstance = new DummyService({}, {})
-      })
-
       it('handles NotFound errors', async function() {
-        serviceInstance.handle = () => {
-          throw new NotFound()
+        class ThrowingService extends DummyService {
+          async handle() {
+            throw new NotFound()
+          }
         }
         expect(
-          await serviceInstance.invokeHandler({
-            namedParamA: 'bar.bar.bar',
-          })
+          await ThrowingService.invoke({}, {}, { namedParamA: 'bar.bar.bar' })
         ).to.deep.equal({
           color: 'red',
           message: 'not found',
@@ -291,13 +285,13 @@ describe('BaseService', function() {
       })
 
       it('handles Inaccessible errors', async function() {
-        serviceInstance.handle = () => {
-          throw new Inaccessible()
+        class ThrowingService extends DummyService {
+          async handle() {
+            throw new Inaccessible()
+          }
         }
         expect(
-          await serviceInstance.invokeHandler({
-            namedParamA: 'bar.bar.bar',
-          })
+          await ThrowingService.invoke({}, {}, { namedParamA: 'bar.bar.bar' })
         ).to.deep.equal({
           color: 'lightgray',
           message: 'inaccessible',
@@ -305,13 +299,13 @@ describe('BaseService', function() {
       })
 
       it('handles InvalidResponse errors', async function() {
-        serviceInstance.handle = () => {
-          throw new InvalidResponse()
+        class ThrowingService extends DummyService {
+          async handle() {
+            throw new InvalidResponse()
+          }
         }
         expect(
-          await serviceInstance.invokeHandler({
-            namedParamA: 'bar.bar.bar',
-          })
+          await ThrowingService.invoke({}, {}, { namedParamA: 'bar.bar.bar' })
         ).to.deep.equal({
           color: 'lightgray',
           message: 'invalid',
@@ -319,13 +313,13 @@ describe('BaseService', function() {
       })
 
       it('handles Deprecated', async function() {
-        serviceInstance.handle = () => {
-          throw new Deprecated()
+        class ThrowingService extends DummyService {
+          async handle() {
+            throw new Deprecated()
+          }
         }
         expect(
-          await serviceInstance.invokeHandler({
-            namedParamA: 'bar.bar.bar',
-          })
+          await ThrowingService.invoke({}, {}, { namedParamA: 'bar.bar.bar' })
         ).to.deep.equal({
           color: 'lightgray',
           message: 'no longer available',
@@ -333,13 +327,13 @@ describe('BaseService', function() {
       })
 
       it('handles InvalidParameter errors', async function() {
-        serviceInstance.handle = () => {
-          throw new InvalidParameter()
+        class ThrowingService extends DummyService {
+          async handle() {
+            throw new InvalidParameter()
+          }
         }
         expect(
-          await serviceInstance.invokeHandler({
-            namedParamA: 'bar.bar.bar',
-          })
+          await ThrowingService.invoke({}, {}, { namedParamA: 'bar.bar.bar' })
         ).to.deep.equal({
           color: 'red',
           message: 'invalid parameter',
@@ -431,7 +425,7 @@ describe('BaseService', function() {
 
     it('handles the request', async function() {
       expect(mockHandleRequest).to.have.been.calledOnce
-      const { handler: requestHandler } = mockHandleRequest.getCall(0).args[0]
+      const { handler: requestHandler } = mockHandleRequest.getCall(0).args[1]
 
       const mockSendBadge = sinon.spy()
       const mockRequest = {
diff --git a/services/cache-headers.js b/services/cache-headers.js
new file mode 100644
index 0000000000..baca92da87
--- /dev/null
+++ b/services/cache-headers.js
@@ -0,0 +1,99 @@
+'use strict'
+
+const assert = require('assert')
+const Joi = require('joi')
+const coalesce = require('../lib/coalesce')
+
+const serverStartTimeGMTString = new Date().toGMTString()
+const serverStartTimestamp = Date.now()
+
+const queryParamSchema = Joi.object({
+  // Not using nonNegativeInteger because it's not required.
+  maxAge: Joi.number()
+    .integer()
+    .min(0),
+}).required()
+
+function coalesceCacheLength(
+  cacheHeaderConfig,
+  serviceCacheLengthSeconds,
+  queryParams
+) {
+  const { defaultCacheLengthSeconds } = cacheHeaderConfig
+  // The config returns a number so this would only fail if we break the
+  // wiring. Better to fail obviously than silently.
+  assert(defaultCacheLengthSeconds !== undefined)
+
+  const ourCacheLength = coalesce(
+    serviceCacheLengthSeconds,
+    defaultCacheLengthSeconds
+  )
+
+  const { value: { maxAge: overrideCacheLength } = {}, error } = Joi.validate(
+    queryParams,
+    queryParamSchema,
+    { allowUnknown: true }
+  )
+
+  if (!error && overrideCacheLength !== undefined) {
+    // The user can request _more_ caching, but not less.
+    return Math.max(overrideCacheLength, ourCacheLength)
+  } else {
+    return ourCacheLength
+  }
+}
+
+function setHeadersForCacheLength(res, cacheLengthSeconds) {
+  const now = new Date()
+  const nowGMTString = now.toGMTString()
+
+  // Send both Cache-Control max-age and Expires in case the client implements
+  // HTTP/1.0 but not HTTP/1.1.
+  let cacheControl, expires
+  if (cacheLengthSeconds === 0) {
+    // Prevent as much downstream caching as possible.
+    cacheControl = 'no-cache, no-store, must-revalidate'
+    expires = nowGMTString
+  } else {
+    cacheControl = `max-age=${cacheLengthSeconds}`
+    expires = new Date(now.getTime() + cacheLengthSeconds * 1000).toGMTString()
+  }
+
+  res.setHeader('Date', nowGMTString)
+  res.setHeader('Cache-Control', cacheControl)
+  res.setHeader('Expires', expires)
+}
+
+function setCacheHeaders({
+  cacheHeaderConfig,
+  serviceCacheLengthSeconds,
+  queryParams,
+  res,
+}) {
+  const cacheLengthSeconds = coalesceCacheLength(
+    cacheHeaderConfig,
+    serviceCacheLengthSeconds,
+    queryParams
+  )
+  setHeadersForCacheLength(res, cacheLengthSeconds)
+}
+
+const staticCacheControlHeader = `max-age=${24 * 3600}` // 1 day.
+function setCacheHeadersForStaticResource(res) {
+  res.setHeader('Cache-Control', staticCacheControlHeader)
+  res.setHeader('Last-Modified', serverStartTimeGMTString)
+}
+
+function serverHasBeenUpSinceResourceCached(req) {
+  return (
+    serverStartTimestamp <= new Date(req.headers['if-modified-since']).getTime()
+  )
+}
+
+module.exports = {
+  coalesceCacheLength,
+  setCacheHeaders,
+  setHeadersForCacheLength,
+  setCacheHeadersForStaticResource,
+  serverHasBeenUpSinceResourceCached,
+}
diff --git a/services/cache-headers.spec.js b/services/cache-headers.spec.js
new file mode 100644
index 0000000000..2a3562ffdc
--- /dev/null
+++ b/services/cache-headers.spec.js
@@ -0,0 +1,173 @@
+'use strict'
+
+const { test, given } = require('sazerac')
+const chai = require('chai')
+const { expect } = require('chai')
+const sinon = require('sinon')
+const httpMocks = require('node-mocks-http')
+const {
+  coalesceCacheLength,
+  setHeadersForCacheLength,
+  setCacheHeaders,
+  setCacheHeadersForStaticResource,
+  serverHasBeenUpSinceResourceCached,
+} = require('./cache-headers')
+
+chai.use(require('chai-datetime'))
+
+describe('Cache header functions', function() {
+  let res
+  beforeEach(function() {
+    res = httpMocks.createResponse()
+  })
+
+  describe('coalesceCacheLength', function() {
+    const exampleCacheConfig = { defaultCacheLengthSeconds: 777 }
+    test(coalesceCacheLength, () => {
+      given(exampleCacheConfig, undefined, {}).expect(777)
+      given(exampleCacheConfig, 900, {}).expect(900)
+      given(exampleCacheConfig, 900, { maxAge: 1000 }).expect(1000)
+      given(exampleCacheConfig, 900, { maxAge: 400 }).expect(900)
+      given(exampleCacheConfig, 900, { maxAge: '-1000' }).expect(900)
+      given(exampleCacheConfig, 900, { maxAge: '' }).expect(900)
+      given(exampleCacheConfig, 900, { maxAge: 'not a number' }).expect(900)
+    })
+  })
+
+  describe('setHeadersForCacheLength', function() {
+    let sandbox
+    beforeEach(function() {
+      sandbox = sinon.createSandbox()
+      sandbox.useFakeTimers()
+    })
+    afterEach(function() {
+      sandbox.restore()
+      sandbox = undefined
+    })
+
+    it('should set the correct Date header', function() {
+      // Confidence check.
+      expect(res._headers.date).to.equal(undefined)
+
+      // Act.
+      setHeadersForCacheLength(res, 123)
+
+      // Assert.
+      const now = new Date().toGMTString()
+      expect(res._headers.date).to.equal(now)
+    })
+
+    context('cacheLengthSeconds is zero', function() {
+      beforeEach(function() {
+        setHeadersForCacheLength(res, 0)
+      })
+
+      it('should set the expected Cache-Control header', function() {
+        expect(res._headers['cache-control']).to.equal(
+          'no-cache, no-store, must-revalidate'
+        )
+      })
+
+      it('should set the expected Expires header', function() {
+        expect(res._headers.expires).to.equal(new Date().toGMTString())
+      })
+    })
+
+    context('cacheLengthSeconds is nonzero', function() {
+      beforeEach(function() {
+        setHeadersForCacheLength(res, 123)
+      })
+
+      it('should set the expected Cache-Control header', function() {
+        expect(res._headers['cache-control']).to.equal('max-age=123')
+      })
+
+      it('should set the expected Expires header', function() {
+        const expires = new Date(Date.now() + 123 * 1000).toGMTString()
+        expect(res._headers.expires).to.equal(expires)
+      })
+    })
+  })
+
+  describe('setCacheHeaders', function() {
+    it('sets the expected fields', function() {
+      const expectedFields = ['date', 'cache-control', 'expires']
+      expectedFields.forEach(field =>
+        expect(res._headers[field]).to.equal(undefined)
+      )
+
+      setCacheHeaders({
+        cacheHeaderConfig: { defaultCacheLengthSeconds: 1234 },
+        serviceCacheLengthSeconds: 567,
+        queryParams: { maxAge: 999999 },
+        res,
+      })
+
+      expectedFields.forEach(field =>
+        expect(res._headers[field])
+          .to.be.a('string')
+          .and.have.lengthOf.at.least(1)
+      )
+    })
+  })
+
+  describe('setCacheHeadersForStaticResource', function() {
+    beforeEach(function() {
+      setCacheHeadersForStaticResource(res)
+    })
+
+    it('should set the expected Cache-Control header', function() {
+      expect(res._headers['cache-control']).to.equal(`max-age=${24 * 3600}`)
+    })
+
+    it('should set the expected Last-Modified header', function() {
+      const lastModified = res._headers['last-modified']
+      expect(new Date(lastModified)).to.be.withinTime(
+        // Within the last 60 seconds.
+        new Date(Date.now() - 60 * 1000),
+        new Date()
+      )
+    })
+  })
+
+  describe('serverHasBeenUpSinceResourceCached', function() {
+    // The stringified req's are hard to understand. I thought Sazerac
+    // provided a way to override the describe message, though I can't find it.
+    context('when there is no If-Modified-Since header', function() {
+      it('returns false', function() {
+        const req = httpMocks.createRequest()
+        expect(serverHasBeenUpSinceResourceCached(req)).to.equal(false)
+      })
+    })
+    context('when the If-Modified-Since header is invalid', function() {
+      it('returns false', function() {
+        const req = httpMocks.createRequest({
+          headers: { 'If-Modified-Since': 'this-is-not-a-date' },
+        })
+        expect(serverHasBeenUpSinceResourceCached(req)).to.equal(false)
+      })
+    })
+    context(
+      'when the If-Modified-Since header is before the process started',
+      function() {
+        it('returns false', function() {
+          const req = httpMocks.createRequest({
+            headers: { 'If-Modified-Since': '2018-02-01T05:00:00.000Z' },
+          })
+          expect(serverHasBeenUpSinceResourceCached(req)).to.equal(false)
+        })
+      }
+    )
+    context(
+      'when the If-Modified-Since header is after the process started',
+      function() {
+        it('returns true', function() {
+          const req = httpMocks.createRequest({
+            headers: { 'If-Modified-Since': new Date().toGMTString() },
+          })
+          expect(serverHasBeenUpSinceResourceCached(req)).to.equal(true)
+        })
+      }
+    )
+  })
+})
diff --git a/services/flip/flip.service.js b/services/flip/flip.service.js
new file mode 100644
index 0000000000..07bcb963cf
--- /dev/null
+++ b/services/flip/flip.service.js
@@ -0,0 +1,33 @@
+'use strict'
+
+const NonMemoryCachingBaseService = require('../base-non-memory-caching')
+
+let bitFlip = false
+
+// Production cache debugging.
+module.exports = class Flip extends NonMemoryCachingBaseService {
+  static get category() {
+    return 'debug'
+  }
+
+  static get route() {
+    return { base: 'flip', pattern: '' }
+  }
+
+  static get defaultBadgeData() {
+    return { label: 'flip' }
+  }
+
+  static render({ bit }) {
+    if (bit) {
+      return { message: 'on', color: 'brightgreen' }
+    } else {
+      return { message: 'off', color: 'red' }
+    }
+  }
+
+  handle() {
+    bitFlip = !bitFlip
+    return this.constructor.render({ bit: bitFlip })
+  }
+}
diff --git a/services/flip/flip.tester.js b/services/flip/flip.tester.js
new file mode 100644
index 0000000000..49250b1c2e
--- /dev/null
+++ b/services/flip/flip.tester.js
@@ -0,0 +1,12 @@
+'use strict'
+
+const t = require('../create-service-tester')()
+module.exports = t
+
+t.create('First request')
+  .get('.json')
+  .expectJSON({ name: 'flip', value: 'on' })
+
+t.create('Second request')
+  .get('.json')
+  .expectJSON({ name: 'flip', value: 'off' })
diff --git a/services/legacy-service.js b/services/legacy-service.js
index 9dbcddda8e..ebf6e3514e 100644
--- a/services/legacy-service.js
+++ b/services/legacy-service.js
@@ -8,13 +8,11 @@ class LegacyService extends BaseService {
     throw Error(`registerLegacyRouteHandler() not implemented for ${this.name}`)
   }
 
-  static register(
-    { camp, handleRequest: cache, githubApiProvider },
-    serviceConfig
-  ) {
+  static register({ camp, handleRequest, githubApiProvider }, serviceConfig) {
+    const { cache: cacheHeaderConfig } = serviceConfig
     this.registerLegacyRouteHandler({
       camp,
-      cache,
+      cache: (...args) => handleRequest(cacheHeaderConfig, ...args),
       githubApiProvider,
     })
   }
diff --git a/services/time/time.service.js b/services/time/time.service.js
index e3c3e858e5..7638b98d37 100644
--- a/services/time/time.service.js
+++ b/services/time/time.service.js
@@ -1,8 +1,8 @@
 'use strict'
 
-const BaseService = require('../base')
+const NonMemoryCachingBaseService = require('../base-non-memory-caching')
 
-module.exports = class Time extends BaseService {
+module.exports = class Time extends NonMemoryCachingBaseService {
   async handle() {
     return { message: new Date() }
   }