diff --git a/.gitignore b/.gitignore
index 5d49397..8b13789 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1 @@
-/tests/test_output_stream
 
diff --git a/faststreams.nimble b/faststreams.nimble
index f470a6c..0f744ad 100644
--- a/faststreams.nimble
+++ b/faststreams.nimble
@@ -11,6 +11,11 @@ requires "nim >= 0.17.0",
          "ranges",
          "std_shims"
 
-task test, "run tests":
-  exec "nim c -r tests/test_output_stream.nim"
+import ospaths, strutils
+
+task test, "Run tests":
+  for filename in listFiles("tests"):
+    if filename.startsWith("tests" / "test_") and filename.endsWith(".nim"):
+      exec "nim c -r " & filename
+      rmFile filename[0..^5]
 
diff --git a/faststreams/input_stream.nim b/faststreams/input_stream.nim
index f7753dd..ae7f1b3 100644
--- a/faststreams/input_stream.nim
+++ b/faststreams/input_stream.nim
@@ -101,7 +101,7 @@ proc eob*(s: ByteStream): bool {.inline.} =
   s.head != s.bufferEnd
 
 proc peek*(s: ByteStream): byte {.inline.} =
-  assert s.head != s.bufferEnd
+  doAssert s.head != s.bufferEnd
   return s.head[]
 
 when debugHelpers:
@@ -121,7 +121,7 @@ proc read*(s: var ByteStream): byte =
 
 proc checkReadAhead(s: ByteStreamVar, n: int): ptr byte =
   result = s.head
-  assert distance(s.head, s.bufferEnd) >= n
+  doAssert distance(s.head, s.bufferEnd) >= n
   s.head = s.head.shift(n)
 
 template readBytes*(s: ByteStreamVar, n: int): auto =
@@ -133,9 +133,9 @@ proc next*(s: var ByteStream): Option[byte] =
 
 proc bufferPos(s: ByteStream, pos: int): ptr byte =
   let shiftFromEnd = pos - s.bufferEndPos
-  assert shiftFromEnd < 0
+  doAssert shiftFromEnd < 0
   result = s.bufferEnd.shift shiftFromEnd
-  assert result >= s.bufferStart
+  doAssert result >= s.bufferStart
 
 proc pos*(s: ByteStream): int {.inline.} =
   s.bufferEndPos - distance(s.head, s.bufferEnd)
@@ -148,7 +148,7 @@ proc `[]`*(s: ByteStream, pos: int): byte {.inline.} =
 
 proc rewind*(s: var ByteStream, delta: int) =
   s.head = s.head.shift(-delta)
-  assert s.head >= s.bufferStart
+  doAssert s.head >= s.bufferStart
 
 proc rewindTo*(s: var ByteStream, pos: int) {.inline.} =
   s.head = s.bufferPos(pos)
diff --git a/faststreams/output_stream.nim b/faststreams/output_stream.nim
index ff06991..45777ff 100644
--- a/faststreams/output_stream.nim
+++ b/faststreams/output_stream.nim
@@ -91,7 +91,7 @@ proc getOutput*(s: OutputStreamVar, T: type string): string =
   else:
     result = newStringOfCap(s.pos)
     for page in s.pages:
-      assert page.delayedWrites == 0
+      doAssert page.delayedWrites == 0
       result.add page.buffer.toOpenArray(page.startOffset.int,
                                          page.buffer.len - 1)
 
@@ -110,7 +110,7 @@ proc flushDelayedPages*(s: OutputStreamVar) =
     # Send to output
 
 proc delayFixedSizeWrite*(s: OutputStreamVar, size: int): DelayedWriteCursor =
-  assert size < pageSize
+  doAssert size < pageSize
 
   let remainingBytesInPage = distance(s.head, s.bufferEnd)
   if size > remainingBytesInPage:
@@ -132,7 +132,7 @@ proc delayVarSizeWrite*(s: OutputStreamVar, maxSize: int): DelayedWriteCursor =
 
 proc decRef(x: var int16): int16 =
   result = x - 1
-  assert result >= 0
+  doAssert result >= 0
   x = result
 
 proc endWrite*(cursor: DelayedWriteCursor, data: openarray[byte]) =
diff --git a/tests/test_input_stream.nim b/tests/test_input_stream.nim
index 922ab06..31ea12c 100644
--- a/tests/test_input_stream.nim
+++ b/tests/test_input_stream.nim
@@ -3,7 +3,7 @@ import
   ../faststreams
 
 suite "input stream":
-  test "string output":
+  test "string input":
     var input = repeat("1234 5678 90AB CDEF\n", 1000)
     var stream = memoryStream(input)
 
diff --git a/tests/test_output_stream.nim b/tests/test_output_stream.nim
index 0d5cc62..228c549 100644
--- a/tests/test_output_stream.nim
+++ b/tests/test_output_stream.nim
@@ -17,5 +17,6 @@ suite "output stream":
       altOutput.add '\n'
 
     let streamOutput = s.getOutput
-    check streamOutput == altOutput
+    # without the cast, in nim-0.19.0: "Error: type mismatch: got <seq[byte], string>" (for the `==` proc)
+    check cast[string](streamOutput) == altOutput