diff --git a/tests/official/fixtures_utils_v0_8_1.nim b/tests/official/fixtures_utils_v0_8_1.nim
deleted file mode 100644
index e6838f98e..000000000
--- a/tests/official/fixtures_utils_v0_8_1.nim
+++ /dev/null
@@ -1,117 +0,0 @@
-# beacon_chain
-# Copyright (c) 2018-Present Status Research & Development GmbH
-# Licensed and distributed under either of
-#   * MIT license (license terms in the root directory or at http://opensource.org/licenses/MIT).
-#   * Apache v2 license (license terms in the root directory or at http://www.apache.org/licenses/LICENSE-2.0).
-# at your option. This file may not be copied, modified, or distributed except according to those terms.
-
-import
-  # Standard library
-  os, strutils,
-  # Status libs
-  stew/byteutils,
-  serialization, json_serialization,
-  # Beacon chain internals
-  ../../beacon_chain/spec/datatypes
-
-export  # Workaround:
-  #   - https://github.com/status-im/nim-serialization/issues/4
-  #   - https://github.com/status-im/nim-serialization/issues/5
-  #   - https://github.com/nim-lang/Nim/issues/11225
-  serialization.readValue
-
-# Process legacy EF test format (up to 0.8.1)
-# -------------------------------------------
-
-type
-  # TODO: use ref object to avoid allocating
-  #       so much on the stack - pending https://github.com/status-im/nim-json-serialization/issues/3
-
-  TestConstants* = object
-    SHARD_COUNT*: int
-    TARGET_COMMITTEE_SIZE*: int
-    MAX_BALANCE_CHURN_QUOTIENT*: int
-    MAX_VALIDATORS_PER_COMMITTEE*: int
-    MIN_PER_EPOCH_CHURN_LIMIT*: int
-    SHUFFLE_ROUND_COUNT*: int
-    DEPOSIT_CONTRACT_TREE_DEPTH*: int
-    MIN_DEPOSIT_AMOUNT*: uint64
-    MAX_EFFECTIVE_BALANCE*: uint64
-    EJECTION_BALANCE*: uint64
-    GENESIS_FORK_VERSION*: uint32
-    GENESIS_SLOT*: Slot
-    GENESIS_EPOCH*: Epoch
-    GENESIS_START_SHARD*: uint64
-    BLS_WITHDRAWAL_PREFIX*: array[1, byte]
-    SECONDS_PER_SLOT*: uint64
-    MIN_ATTESTATION_INCLUSION_DELAY*: uint64
-    SLOTS_PER_EPOCH*: int
-    MIN_SEED_LOOKAHEAD*: int
-    MAX_SEED_LOOKAHEAD*: int
-    EPOCHS_PER_ETH1_VOTING_PERIOD*: uint64
-    SLOTS_PER_HISTORICAL_ROOT*: int
-    MIN_VALIDATOR_WITHDRAWABILITY_DELAY*: uint64
-    PERSISTENT_COMMITTEE_PERIOD*: uint64
-    LATEST_RANDAO_MIXES_LENGTH*: int
-    EPOCHS_PER_HISTORICAL_VECTOR*: int
-    EPOCHS_PER_SLASHINGS_VECTOR*: int
-    BASE_REWARD_FACTOR*: uint64
-    WHISTLEBLOWER_REWARD_QUOTIENT*: uint64
-    PROPOSER_REWARD_QUOTIENT*: uint64
-    INACTIVITY_PENALTY_QUOTIENT*: uint64
-    MIN_SLASHING_PENALTY_QUOTIENT*: int
-    MAX_PROPOSER_SLASHINGS*: int
-    MAX_ATTESTER_SLASHINGS*: int
-    MAX_ATTESTATIONS*: int
-    MAX_DEPOSITS*: int
-    MAX_VOLUNTARY_EXITS*: int
-    MAX_TRANSFERS*: int
-    DOMAIN_BEACON_PROPOSER*: DomainType
-    DOMAIN_RANDAO*: DomainType
-    DOMAIN_BEACON_ATTESTER*: DomainType
-    DOMAIN_DEPOSIT*: DomainType
-    DOMAIN_VOLUNTARY_EXIT*: DomainType
-    DOMAIN_TRANSFER*: DomainType
-
-  Tests*[T] = object
-    title*: string
-    summary*: string
-    forks_timeline*: string
-    forks*: seq[string]
-    config*: string
-    runner*: string
-    handler*: string
-    test_cases*: seq[T]
-
-const
-  FixturesDir* = currentSourcePath.rsplit(DirSep, 1)[0] / "fixtures"
-  JsonTestsDir* = FixturesDir / "json_tests_v0.8.1"
-
-# #######################
-# Default init
-proc default*(T: typedesc): T = discard
-
-# #######################
-# JSON deserialization
-
-proc readValue*[N: static int](r: var JsonReader, a: var array[N, byte]) {.inline.} =
-  # Needed for;
-  #   - BLS_WITHDRAWAL_PREFIX
-  #   - Fork datatypes
-  # TODO: are all bytes and bytearray serialized as hex?
-  #       if so export that to nim-eth
-  hexToByteArray(r.readValue(string), a)
-
-proc readValue*(r: var JsonReader, a: var seq[byte]) {.inline.} =
-  ## Custom deserializer for seq[byte]
-  a = hexToSeqByte(r.readValue(string))
-
-proc parseTests*(jsonPath: string, T: typedesc): Tests[T] =
-  try:
-    debugEcho "          [Debug] Loading file: \"", jsonPath, '\"'
-    result = Json.loadFile(jsonPath, Tests[T])
-  except SerializationError as err:
-    writeStackTrace()
-    stderr.write "Json load issue for file \"", jsonPath, "\"\n"
-    stderr.write err.formatMsg(jsonPath), "\n"
-    quit 1
diff --git a/tests/official/test_fixture_ssz_static.nim b/tests/official/test_fixture_ssz_static.nim
deleted file mode 100644
index c4f8bc107..000000000
--- a/tests/official/test_fixture_ssz_static.nim
+++ /dev/null
@@ -1,215 +0,0 @@
-# beacon_chain
-# Copyright (c) 2018 Status Research & Development GmbH
-# Licensed and distributed under either of
-#   * MIT license (license terms in the root directory or at http://opensource.org/licenses/MIT).
-#   * Apache v2 license (license terms in the root directory or at http://www.apache.org/licenses/LICENSE-2.0).
-# at your option. This file may not be copied, modified, or distributed except according to those terms.
-
-import
-  # Standard library
-  os, strutils, strformat, tables, unittest, sequtils, typetraits,
-  # Status libs
-  stew/[byteutils, bitseqs], nimcrypto/hash,
-  serialization/testing/tracing,
-  json_serialization, json_serialization/lexer,
-  # Beacon chain internals
-  ../../beacon_chain/ssz,
-  ../../beacon_chain/spec/[datatypes, validator, digest, crypto],
-  # Test utilities
-  ../testutil,
-  ./fixtures_utils_v0_8_1
-
-const
-  failFast = defined(debug) and false
-  traceOnFailure = defined(debug)
-
-type
-  SpecObject[T] = ref object of RootObj
-    obj: ref T
-
-  SszStaticTest* = object
-    obj: RootRef
-    objType, objJsonRepr: string
-    expectedBytes: seq[byte]
-    expectedRootHash, expectedSigHash: Eth2Digest
-    hasSigHash: bool
-    line: int
-
-  ReaderProc = proc(r: var JsonReader): RootRef {.cdecl, gcsafe.}
-  TestingProc = proc(file: string, test: SszStaticTest) {.cdecl, gcsafe.}
-
-  SpecTypeVtable = object
-    reader: ReaderProc
-    tester: TestingProc
-
-let testsDir = JsonTestsDir / "ssz_static" / "core"
-let minDevTestFile = getTempDir() / "minimal_ssz_test.json"
-
-var specTypesRTTI = initTable[string, SpecTypeVtable]()
-
-proc readerImpl[T](r: var JsonReader): RootRef {.cdecl, gcsafe.} =
-  var res = SpecObject[T](obj: new T)
-  res.obj[] = r.readValue(T)
-  RootRef(res)
-
-# TODO:
-# Fun fact: With mainnet settings, the BeaconState object
-# is too large to safely exist as a stack variable. The
-# `testerImpl` procedure below will trigger a segmentation
-# fault on its very first line because of it.
-#
-# To work-around this issue, this file uses ref objects
-# to store the loaded test cases, but we must compare them
-# by value:
-template valuesAreEqual[T](a, b: ref T): bool =
-  a[] == b[]
-
-template valuesAreEqual[T](a, b: T): bool =
-  a == b
-
-template `$`(x: ref auto): string =
-  $(x[])
-
-proc readSszValueRef*(input: openarray[byte], T: type): ref T =
-  new result
-  result[] = readSszValue(input, T)
-
-proc testerImpl[T](path: string, sszTest: SszStaticTest) {.cdecl, gcsafe.} =
-  doAssert sszTest.obj != nil
-  var obj = SpecObject[T](sszTest.obj)
-
-  test &"test case on line {sszTest.line}":
-    template execTest(testOpName, testOp, expectedRes) =
-      let ourRes = testOp
-      let success = valuesAreEqual(ourRes, expectedRes)
-      if not success and traceOnFailure:
-        {.gcsafe.}:
-          echo "====== ", testOpName, " failed ", path, ":", sszTest.line
-          echo " our result:"
-          echo "  ", ourRes
-          echo " expected result:"
-          echo "  ", expectedRes
-          when defined(serialization_tracing):
-            tracingEnabled = true
-            discard testOp
-            tracingEnabled = false
-          echo "======================================================"
-          if failFast: quit 1
-
-      # TODO BEWARE: Passing the boolean expression to `check` directly
-      # will trigger a Nim compilation bomb. This is most likely caused
-      # by a mis-behaving generics instantiations cache when a function
-      # is explicitly instantiated to get its address.
-      # There is a recursive instantiation loop of system's `$` operator.
-      check success
-
-    execTest "serialization",
-              (let ourBytes = SSZ.encode(obj.obj[]); ourBytes),
-              sszTest.expectedBytes
-
-    execTest "root hash check",
-              hash_tree_root(obj.obj[]),
-              sszTest.expectedRootHash
-
-    when hasSigningRoot(T):
-      doAssert sszTest.hasSigHash
-      execTest "sig hash check",
-               signingRoot(obj.obj[]),
-               sszTest.expectedSigHash
-
-    execTest "roundtrip",
-           readSszValueRef(sszTest.expectedBytes, T),
-           obj.obj
-
-template addSpecTypeRTTI(T: type) =
-  var reader = readerImpl[T]
-  var tester = testerImpl[T]
-  specTypesRTTI.add(T.name, SpecTypeVtable(reader: reader,
-                                           tester: tester))
-foreachSpecType(addSpecTypeRTTI)
-
-proc runTest(path: string, test: SszStaticTest) =
-  if test.objType != "Unsupported":
-    specTypesRTTI[test.objType].tester(path, test)
-
-proc advanceToClosingBrace(lexer: var JsonLexer, openedBraces = 1) =
-  var closedBraces = 0
-  while closedBraces < openedBraces:
-    while lexer.tok notin {tkCurlyLe, tkCurlyRi}:
-      lexer.next
-    if lexer.tok == tkCurlyLe:
-      dec closedBraces
-    else:
-      inc closedBraces
-    lexer.next
-
-proc readValue*(r: var JsonReader, result: var SszStaticTest) {.gcsafe.} =
-  r.skipToken tkCurlyLe
-
-  if r.lexer.tok != tkString:
-    r.raiseUnexpectedToken(etString)
-
-  var reader: ReaderProc
-  let key = r.lexer.strVal
-  {.gcsafe.}:
-    if not specTypesRTTI.hasKey(key):
-      result.objType = "Unsupported"
-      r.lexer.advanceToClosingBrace
-      return
-
-    result.objType = key
-    result.line = r.lexer.line
-    reader = specTypesRTTI[key].reader
-
-  r.lexer.next
-  r.skipToken tkColon
-  r.skipToken tkCurlyLe
-
-  while r.lexer.tok == tkString:
-    # TODO: I was hit by a very nasty Nim bug here.
-    # If you use `let` on the next line, the variable will be
-    # aliased to `r.lexer.strVar` instead of being copied.
-    # This will create problems, because the value is modified
-    # on the next line.
-    var field = r.lexer.strVal
-    r.lexer.next
-    r.skipToken tkColon
-
-    case field
-    of "value":
-      result.obj = reader(r)
-    of "serialized":
-      result.expectedBytes = hexToSeqByte r.readValue(string)
-    of "root":
-      result.expectedRootHash = Eth2Digest.fromHex r.readValue(string)
-    of "signing_root":
-      result.expectedSigHash = Eth2Digest.fromHex r.readValue(string)
-      result.hasSigHash = true
-    else:
-      r.raiseUnexpectedField(field, type(result).name)
-
-    if r.lexer.tok == tkComma:
-      r.lexer.next()
-    else:
-      break
-
-  r.skipToken tkCurlyRi
-  r.skipToken tkCurlyRi
-
-  when failFast:
-    # This will produce faster failures in debug builds
-    {.gcsafe.}: runTest result
-
-proc executeSuite(path: string) =
-  let sszSuite = path.parseTests SszStaticTest
-  suite &"{path}: {sszSuite.title}":
-    for sszTest in sszSuite.test_cases:
-      runTest path, sszTest
-
-if fileExists(minDevTestFile):
-  executeSuite minDevTestFile
-
-for kind, path in walkDir(testsDir):
-  if kind notin {pcFile, pcLinkToFile}: continue
-  if const_preset in path:
-    executeSuite path
diff --git a/tests/official/test_fixture_ssz_static.nim.cfg b/tests/official/test_fixture_ssz_static.nim.cfg
deleted file mode 100644
index 515f0a270..000000000
--- a/tests/official/test_fixture_ssz_static.nim.cfg
+++ /dev/null
@@ -1,2 +0,0 @@
--d:"serialization_tracing"
--d:"ssz_testing"
diff --git a/tests/official/test_fixture_ssz_uint.nim b/tests/official/test_fixture_ssz_uint.nim
deleted file mode 100644
index c5c93951a..000000000
--- a/tests/official/test_fixture_ssz_uint.nim
+++ /dev/null
@@ -1,115 +0,0 @@
-# beacon_chain
-# Copyright (c) 2018 Status Research & Development GmbH
-# Licensed and distributed under either of
-#   * MIT license (license terms in the root directory or at http://opensource.org/licenses/MIT).
-#   * Apache v2 license (license terms in the root directory or at http://www.apache.org/licenses/LICENSE-2.0).
-# at your option. This file may not be copied, modified, or distributed except according to those terms.
-
-import
-  # Standard library
-  ospaths, unittest, sequtils,
-  # Status libs
-  stint, serialization,
-  # Beacon chain internals
-  ../../beacon_chain/ssz,
-  ../../beacon_chain/spec/datatypes,
-  # Test utilities
-  ../testutil,
-  ./fixtures_utils_v0_8_1
-
-type
-  SSZUint* = object
-    `type`*: string
-    value*: string
-    valid*: bool
-    ssz*: seq[byte]
-    tags*: seq[string]
-
-const
-  TestsDir = JsonTestsDir / "ssz_generic" / "uint"
-
-func to(val: string, T: typedesc): T =
-  when T is StUint:
-    val.parse(T)
-  else: # result is unsigned int
-    val.parse(StUint[8 * sizeof(T)]).data
-
-# TODO strformat for the skipped checks
-
-template checkSerialization(test: SSZUint, T: typedesc) =
-  if test.valid:
-    let value: T = test.value.to(T)
-    let serialized = SSZ.encode(value)
-    check(serialized == test.ssz)
-  elif test.value != "":
-    # No SSZ encoding -> expected failing serialization test
-    if test.tags.anyIt(it == "uint_underflow"):
-      # TODO: Stint throws RangeError for negative number parsing
-      #       https://github.com/status-im/nim-stint/blob/ccf87daac1eef15238ff3d6d2edb138e22180d19/stint/io.nim#L130-L132
-      # TODO: Stint checks with an assert that integer is positive or zero
-      #       https://github.com/status-im/nim-stint/blob/ccf87daac1eef15238ff3d6d2edb138e22180d19/stint/io.nim#L35
-      expect RangeError, OverflowError, AssertionError:
-        let value: T = test.value.to(T)
-    else:
-      # TODO tag "uint_overflow" does not throw an exception at the moment
-      echo "         [Skipped - Serialization - TODO]  tags: ", test.tags
-  else:
-    echo "         [Skipped - Serialization - N/A]   tags: ", test.tags
-
-template checkDeserialization(test: SSZUint, T: typedesc) =
-  if test.valid:
-    let deser = SSZ.decode(test.ssz, T)
-    check($deser == test.value)
-  elif test.value == "":
-    # No literal value -> expected failing deserialization test
-    if test.tags.anyIt(it == "wrong_length"):
-      expect IndexError:
-        let deser = SSZ.decode(test.ssz, T)
-    else:
-      echo "         [Skipped - Deserialization]       tags: ", test.tags
-  else:
-    echo "         [Skipped - Deserialization - N/A] tags: ", test.tags
-
-proc runSSZUintTest(inputTests: Tests[SSZUint]) =
-  # We use Stint string -> uint parser + casting
-  # as it's generic over all unsigned integer size
-  # and not just BiggestUint
-  for test in inputTests.test_cases:
-    if test.`type` == "uint8":
-      test.checkSerialization(uint8)
-      test.checkDeserialization(uint8)
-    elif test.`type` == "uint16":
-      test.checkSerialization(uint16)
-      test.checkDeserialization(uint16)
-    elif test.`type` == "uint32":
-      test.checkSerialization(uint32)
-      test.checkDeserialization(uint32)
-    elif test.`type` == "uint64":
-      test.checkSerialization(uint64)
-      test.checkDeserialization(uint64)
-    # TODO: Stint serialization
-    # elif test.`type` == "uint128":
-    #   test.checkSerialization(StUint[128])
-    # elif test.`type` == "uint256":
-    #   test.checkSerialization(StUint[256])
-    else:
-      echo "         [Skipped] uint size: ", test.`type`
-
-suite "Official - 0.8.1 - SSZ unsigned integer tests" & preset():
-  block: # "Integers right at or beyond the bounds of the allowed value range"
-    let uintBounds = parseTests(TestsDir / "uint_bounds.json", SSZUint)
-    test uintBounds.summary & preset():
-      runSSZUintTest(uintBounds)
-
-  block: # "Random integers chosen uniformly over the allowed value range"
-    let uintRandom = parseTests(TestsDir / "uint_random.json", SSZUint)
-    test uintRandom.summary & preset():
-      runSSZUintTest(uintRandom)
-
-  # TODO: pending fix for https://github.com/status-im/nim-beacon-chain/issues/280
-  block: # "Serialized integers that are too short or too long"
-    let uintWrongLength = parseTests(TestsDir / "uint_wrong_length.json", SSZUint)
-    test "[Skipped] " & uintWrongLength.summary & preset():
-      # TODO: pending fix for https://github.com/status-im/nim-beacon-chain/issues/280
-      echo "         [Skipped] Pending https://github.com/status-im/nim-beacon-chain/issues/280"
-      # runSSZUintTest(uintWrongLength)