diff --git a/src/data/program_configuration.js b/src/data/program_configuration.js
index 9d3aa230351..75603644f4f 100644
--- a/src/data/program_configuration.js
+++ b/src/data/program_configuration.js
@@ -116,7 +116,7 @@ class ConstantBinder<T> implements Binder<T> {
         uniform.set(currentValue.constantOr(this.value));
     }
 
-    getBinding(context: Context, location: WebGLUniformLocation): $Subtype<Uniform<*>> {
+    getBinding(context: Context, location: WebGLUniformLocation): $Subtype<Uniform<any>> {
         return (this.type === 'color') ?
             new UniformColor(context, location) :
             new Uniform1f(context, location);
@@ -345,7 +345,7 @@ class CompositeExpressionBinder<T> implements Binder<T> {
  *
  * @private
  */
-class ProgramConfiguration {
+export default class ProgramConfiguration {
     binders: Array<Binder<any>>;
     cacheKey: string;
     layoutAttributes: Array<StructArrayMember>;
@@ -400,9 +400,9 @@ class ProgramConfiguration {
         return self;
     }
 
-    populatePaintArrays(length: number, feature: Feature) {
+    populatePaintArrays(newLength: number, feature: Feature, index: number) {
         for (let i = 0; i < this.binderLen; i++) {
-            this.binders[i].populatePaintArray(length, feature);
+            this.binders[i].populatePaintArray(newLength, feature);
         }
         if (feature.id) {
             const featureId = String(feature.id);
@@ -427,12 +427,12 @@ class ProgramConfiguration {
             for (const pos of posArray) {
                 const feature = vtLayer.feature(pos.index);
 
-                for (const property in this.binders) {
-                    const binder = this.binders[property];
+                for (let i = 0; i < this.binderLen; i++) {
+                    const binder = this.binders[i];
                     if (binder instanceof ConstantBinder) continue;
                     if ((binder: any).expression.isStateDependent === true) {
                         //AHM: Remove after https://github.com/mapbox/mapbox-gl-js/issues/6255
-                        const value = layer.paint.get(property);
+                        const value = layer.paint.get(binder.property);
                         (binder: any).expression = value.value;
                         binder.updatePaintArray(pos.start, pos.end, feature, featureState);
                         dirty = true;
@@ -464,10 +464,10 @@ class ProgramConfiguration {
         return result;
     }
 
-    setUniforms<Properties: Object>(context: Context, uniformBindings: UniformBindings, properties: PossiblyEvaluated<Properties>, globals: GlobalProperties, i: number) {
+    setUniforms<Properties: Object>(context: Context, uniformBindings: UniformBindings, properties: PossiblyEvaluated<Properties>, globals: GlobalProperties) {
         // Uniform state bindings are owned by the Program, but we set them
         // from within the ProgramConfiguraton's binder members.
-        for (; i < this.binderLen; i++) {
+        for (let i = 0; i < this.binderLen; i++) {
             this.binders[i].setUniforms(context, uniformBindings[this.binders[i].uniformName], globals, properties.get(this.binders[i].property));
         }
     }
diff --git a/src/render/draw_fill.js b/src/render/draw_fill.js
index 60df69a7081..3c853898f33 100644
--- a/src/render/draw_fill.js
+++ b/src/render/draw_fill.js
@@ -25,7 +25,6 @@ function drawFill(painter: Painter, sourceCache: SourceCache, layer: FillStyleLa
         return;
     }
 
-    const context = painter.context;
     const colorMode = painter.colorModeForRenderPass();
 
     const pass = (!layer.paint.get('fill-pattern') &&
diff --git a/src/render/draw_line.js b/src/render/draw_line.js
index 96ada917162..50f76e931af 100644
--- a/src/render/draw_line.js
+++ b/src/render/draw_line.js
@@ -4,6 +4,7 @@ import DepthMode from '../gl/depth_mode';
 import Texture from './texture';
 import {
     lineUniformValues,
+    lineGradientUniformValues,
     linePatternUniformValues,
     lineSDFUniformValues
 } from './program/line_program';
diff --git a/src/render/program.js b/src/render/program.js
index bf6c3eb553f..44ec70c9331 100644
--- a/src/render/program.js
+++ b/src/render/program.js
@@ -121,10 +121,7 @@ class Program<Us: UniformBindings> {
         }
 
         if (configuration) {
-            // For whatever reason, initializing `setUniforms`'s
-            // loop iterator here creates consistently better performance:
-            const i = 0;
-            configuration.setUniforms(context, this.binderUniforms, currentProperties, {zoom: (zoom: any)}, i);
+            configuration.setUniforms(context, this.binderUniforms, currentProperties, {zoom: (zoom: any)});
         }
 
         const primitiveSize = {
diff --git a/src/render/program/fill_extrusion_program.js b/src/render/program/fill_extrusion_program.js
index 2de50d700d5..439b178cab6 100644
--- a/src/render/program/fill_extrusion_program.js
+++ b/src/render/program/fill_extrusion_program.js
@@ -9,10 +9,7 @@ import {
     UniformMatrix4fv
 } from '../uniform_binding';
 
-import glMatrix from '@mapbox/gl-matrix';
-const mat3 = glMatrix.mat3;
-const vec3 = glMatrix.vec3;
-const mat4 = glMatrix.mat4;
+import { mat3, vec3, mat4 } from 'gl-matrix';
 import { extend } from '../../util/util';
 
 import type Context from '../../gl/context';
diff --git a/src/render/program/heatmap_program.js b/src/render/program/heatmap_program.js
index 6643272aab2..b93cccbd29c 100644
--- a/src/render/program/heatmap_program.js
+++ b/src/render/program/heatmap_program.js
@@ -1,6 +1,6 @@
 // @flow
 
-import { mat4 } from '@mapbox/gl-matrix';
+import { mat4 } from 'gl-matrix';
 
 import {
     Uniform1i,
diff --git a/src/render/program/hillshade_program.js b/src/render/program/hillshade_program.js
index 6897a5a102b..bc274d49408 100644
--- a/src/render/program/hillshade_program.js
+++ b/src/render/program/hillshade_program.js
@@ -1,6 +1,6 @@
 // @flow
 
-import { mat4 } from '@mapbox/gl-matrix';
+import { mat4 } from 'gl-matrix';
 
 import {
     Uniform1i,
diff --git a/src/render/program/line_program.js b/src/render/program/line_program.js
index 5c8ca9c7a84..cf278a7cf7c 100644
--- a/src/render/program/line_program.js
+++ b/src/render/program/line_program.js
@@ -125,7 +125,7 @@ const lineGradientUniformValues = (
     return extend(lineUniformValues(painter, tile, layer), {
         'u_image': 0
     });
-}
+};
 
 const linePatternUniformValues = (
     painter: Painter,